From 97e1532ef81acb31c30f9e75bf00306c33a77812 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 16 Jan 2019 10:27:59 +0100 Subject: fuse: handle zero sized retrieve correctly Dereferencing req->page_descs[0] will Oops if req->max_pages is zero. Reported-by: syzbot+c1e36d30ee3416289cc0@syzkaller.appspotmail.com Tested-by: syzbot+c1e36d30ee3416289cc0@syzkaller.appspotmail.com Fixes: b2430d7567a3 ("fuse: add per-page descriptor to fuse_req") Cc: # v3.9 Signed-off-by: Miklos Szeredi --- fs/fuse/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index a5e516a40e7a..fc29264011a6 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1742,7 +1742,6 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, req->in.h.nodeid = outarg->nodeid; req->in.numargs = 2; req->in.argpages = 1; - req->page_descs[0].offset = offset; req->end = fuse_retrieve_end; index = outarg->offset >> PAGE_SHIFT; @@ -1757,6 +1756,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, this_num = min_t(unsigned, num, PAGE_SIZE - offset); req->pages[req->num_pages] = page; + req->page_descs[req->num_pages].offset = offset; req->page_descs[req->num_pages].length = this_num; req->num_pages++; -- cgit v1.2.3-58-ga151 From 8a3177db59cd644fde05ba9efee29392dfdec8aa Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 16 Jan 2019 10:27:59 +0100 Subject: cuse: fix ioctl cuse_process_init_reply() doesn't initialize fc->max_pages and thus all cuse bases ioctls fail with ENOMEM. Reported-by: Andreas Steinmetz Fixes: 5da784cce430 ("fuse: add max_pages to init_out") Cc: # v4.20 Signed-off-by: Miklos Szeredi --- fs/fuse/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 76baaa6be393..c2d4099429be 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -628,6 +628,7 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns) get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); fc->pid_ns = get_pid_ns(task_active_pid_ns(current)); fc->user_ns = get_user_ns(user_ns); + fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; } EXPORT_SYMBOL_GPL(fuse_conn_init); @@ -1162,7 +1163,6 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) fc->user_id = d.user_id; fc->group_id = d.group_id; fc->max_read = max_t(unsigned, 4096, d.max_read); - fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ; /* Used by get_root_inode() */ sb->s_fs_info = fc; -- cgit v1.2.3-58-ga151 From 9509941e9c534920ccc4771ae70bd6cbbe79df1c Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Sat, 12 Jan 2019 02:39:05 +0100 Subject: fuse: call pipe_buf_release() under pipe lock Some of the pipe_buf_release() handlers seem to assume that the pipe is locked - in particular, anon_pipe_buf_release() accesses pipe->tmp_page without taking any extra locks. From a glance through the callers of pipe_buf_release(), it looks like FUSE is the only one that calls pipe_buf_release() without having the pipe locked. This bug should only lead to a memory leak, nothing terrible. Fixes: dd3bb14f44a6 ("fuse: support splice() writing to fuse device") Cc: stable@vger.kernel.org Signed-off-by: Jann Horn Signed-off-by: Miklos Szeredi --- fs/fuse/dev.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs') diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index fc29264011a6..809c0f2f9942 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -2077,8 +2077,10 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, ret = fuse_dev_do_write(fud, &cs, len); + pipe_lock(pipe); for (idx = 0; idx < nbuf; idx++) pipe_buf_release(pipe, &bufs[idx]); + pipe_unlock(pipe); out: kvfree(bufs); -- cgit v1.2.3-58-ga151 From a2ebba824106dabe79937a9f29a875f837e1b6d4 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 16 Jan 2019 10:27:59 +0100 Subject: fuse: decrement NR_WRITEBACK_TEMP on the right page NR_WRITEBACK_TEMP is accounted on the temporary page in the request, not the page cache page. Fixes: 8b284dc47291 ("fuse: writepages: handle same page rewrites") Cc: # v3.13 Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/fuse/file.c b/fs/fuse/file.c index ffaffe18352a..a59c16bd90ac 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1782,7 +1782,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req, spin_unlock(&fc->lock); dec_wb_stat(&bdi->wb, WB_WRITEBACK); - dec_node_page_state(page, NR_WRITEBACK_TEMP); + dec_node_page_state(new_req->pages[0], NR_WRITEBACK_TEMP); wb_writeout_inc(&bdi->wb); fuse_writepage_free(fc, new_req); fuse_request_free(new_req); -- cgit v1.2.3-58-ga151 From d88c93f090f708c18195553b352b9f205e65418f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 23 Jan 2019 11:27:02 +0100 Subject: debugfs: fix debugfs_rename parameter checking debugfs_rename() needs to check that the dentries passed into it really are valid, as sometimes they are not (i.e. if the return value of another debugfs call is passed into this one.) So fix this up by properly checking if the two parent directories are errors (they are allowed to be NULL), and if the dentry to rename is not NULL or an error. Cc: stable Signed-off-by: Greg Kroah-Hartman --- fs/debugfs/inode.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs') diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 13b01351dd1c..41ef452c1fcf 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -787,6 +787,13 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, struct dentry *dentry = NULL, *trap; struct name_snapshot old_name; + if (IS_ERR(old_dir)) + return old_dir; + if (IS_ERR(new_dir)) + return new_dir; + if (IS_ERR_OR_NULL(old_dentry)) + return old_dentry; + trap = lock_rename(new_dir, old_dir); /* Source or destination directories don't exist? */ if (d_really_is_negative(old_dir) || d_really_is_negative(new_dir)) -- cgit v1.2.3-58-ga151 From 8e47a457321ca1a74ad194ab5dcbca764bc70731 Mon Sep 17 00:00:00 2001 From: Piotr Jaroszynski Date: Sun, 27 Jan 2019 08:46:45 -0800 Subject: iomap: get/put the page in iomap_page_create/release() migrate_page_move_mapping() expects pages with private data set to have a page_count elevated by 1. This is what used to happen for xfs through the buffer_heads code before the switch to iomap in commit 82cb14175e7d ("xfs: add support for sub-pagesize writeback without buffer_heads"). Not having the count elevated causes move_pages() to fail on memory mapped files coming from xfs. Make iomap compatible with the migrate_page_move_mapping() assumption by elevating the page count as part of iomap_page_create() and lowering it in iomap_page_release(). It causes the move_pages() syscall to misbehave on memory mapped files from xfs. It does not not move any pages, which I suppose is "just" a perf issue, but it also ends up returning a positive number which is out of spec for the syscall. Talking to Michal Hocko, it sounds like returning positive numbers might be a necessary update to move_pages() anyway though. Fixes: 82cb14175e7d ("xfs: add support for sub-pagesize writeback without buffer_heads") Signed-off-by: Piotr Jaroszynski [hch: actually get/put the page iomap_migrate_page() to make it work properly] Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'fs') diff --git a/fs/iomap.c b/fs/iomap.c index a3088fae567b..cb184ff68680 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -116,6 +116,12 @@ iomap_page_create(struct inode *inode, struct page *page) atomic_set(&iop->read_count, 0); atomic_set(&iop->write_count, 0); bitmap_zero(iop->uptodate, PAGE_SIZE / SECTOR_SIZE); + + /* + * migrate_page_move_mapping() assumes that pages with private data have + * their count elevated by 1. + */ + get_page(page); set_page_private(page, (unsigned long)iop); SetPagePrivate(page); return iop; @@ -132,6 +138,7 @@ iomap_page_release(struct page *page) WARN_ON_ONCE(atomic_read(&iop->write_count)); ClearPagePrivate(page); set_page_private(page, 0); + put_page(page); kfree(iop); } @@ -569,8 +576,10 @@ iomap_migrate_page(struct address_space *mapping, struct page *newpage, if (page_has_private(page)) { ClearPagePrivate(page); + get_page(newpage); set_page_private(newpage, page_private(page)); set_page_private(page, 0); + put_page(page); SetPagePrivate(newpage); } -- cgit v1.2.3-58-ga151 From 4ea899ead2786a30aaa8181fefa81a3df4ad28f6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 17 Jan 2019 08:58:58 -0800 Subject: iomap: fix a use after free in iomap_dio_rw Introduce a local wait_for_completion variable to avoid an access to the potentially freed dio struture after dropping the last reference count. Also use the chance to document the completion behavior to make the refcounting clear to the reader of the code. Fixes: ff6a9292e6 ("iomap: implement direct I/O") Reported-by: Chandan Rajendra Reported-by: Darrick J. Wong Signed-off-by: Christoph Hellwig Tested-by: Chandan Rajendra Tested-by: Darrick J. Wong Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) (limited to 'fs') diff --git a/fs/iomap.c b/fs/iomap.c index cb184ff68680..897c60215dd1 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1813,6 +1813,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, loff_t pos = iocb->ki_pos, start = pos; loff_t end = iocb->ki_pos + count - 1, ret = 0; unsigned int flags = IOMAP_DIRECT; + bool wait_for_completion = is_sync_kiocb(iocb); struct blk_plug plug; struct iomap_dio *dio; @@ -1832,7 +1833,6 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, dio->end_io = end_io; dio->error = 0; dio->flags = 0; - dio->wait_for_completion = is_sync_kiocb(iocb); dio->submit.iter = iter; dio->submit.waiter = current; @@ -1887,7 +1887,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, dio_warn_stale_pagecache(iocb->ki_filp); ret = 0; - if (iov_iter_rw(iter) == WRITE && !dio->wait_for_completion && + if (iov_iter_rw(iter) == WRITE && !wait_for_completion && !inode->i_sb->s_dio_done_wq) { ret = sb_init_dio_done_wq(inode->i_sb); if (ret < 0) @@ -1903,7 +1903,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, if (ret <= 0) { /* magic error code to fall back to buffered I/O */ if (ret == -ENOTBLK) { - dio->wait_for_completion = true; + wait_for_completion = true; ret = 0; } break; @@ -1925,8 +1925,24 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, if (dio->flags & IOMAP_DIO_WRITE_FUA) dio->flags &= ~IOMAP_DIO_NEED_SYNC; + /* + * We are about to drop our additional submission reference, which + * might be the last reference to the dio. There are three three + * different ways we can progress here: + * + * (a) If this is the last reference we will always complete and free + * the dio ourselves. + * (b) If this is not the last reference, and we serve an asynchronous + * iocb, we must never touch the dio after the decrement, the + * I/O completion handler will complete and free it. + * (c) If this is not the last reference, but we serve a synchronous + * iocb, the I/O completion handler will wake us up on the drop + * of the final reference, and we will complete and free it here + * after we got woken by the I/O completion handler. + */ + dio->wait_for_completion = wait_for_completion; if (!atomic_dec_and_test(&dio->ref)) { - if (!dio->wait_for_completion) + if (!wait_for_completion) return -EIOCBQUEUED; for (;;) { @@ -1943,9 +1959,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, __set_current_state(TASK_RUNNING); } - ret = iomap_dio_complete(dio); - - return ret; + return iomap_dio_complete(dio); out_free_dio: kfree(dio); -- cgit v1.2.3-58-ga151 From a6279470762c19ba97e454f90798373dccdf6148 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Fri, 25 Jan 2019 11:48:51 +0000 Subject: Btrfs: fix deadlock when allocating tree block during leaf/node split When splitting a leaf or node from one of the trees that are modified when flushing pending block groups (extent, chunk, device and free space trees), we need to allocate a new tree block, which in turn can result in the need to allocate a new block group. After allocating the new block group we may need to flush new block groups that were previously allocated during the course of the current transaction, which is what may cause a deadlock due to attempts to write lock twice the same leaf or node, as when splitting a leaf or node we are holding a write lock on it and its parent node. The same type of deadlock can also happen when increasing the tree's height, since we are holding a lock on the existing root while allocating the tree block to use as the new root node. An example trace when the deadlock happens during the leaf split path is: [27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G W 4.19.16 #1 [27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018 [27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs] (...) [27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246 [27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001 [27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48 [27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000 [27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000 [27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18 [27175.303601] FS: 0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000 [27175.304468] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0 [27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [27175.307940] Call Trace: [27175.308802] btrfs_search_slot+0x779/0x9a0 [btrfs] [27175.309669] ? update_space_info+0xba/0xe0 [btrfs] [27175.310534] btrfs_insert_empty_items+0x67/0xc0 [btrfs] [27175.311397] btrfs_insert_item+0x60/0xd0 [btrfs] [27175.312253] btrfs_create_pending_block_groups+0xee/0x210 [btrfs] [27175.313116] do_chunk_alloc+0x25f/0x300 [btrfs] [27175.313984] find_free_extent+0x706/0x10d0 [btrfs] [27175.314855] btrfs_reserve_extent+0x9b/0x1d0 [btrfs] [27175.315707] btrfs_alloc_tree_block+0x100/0x5b0 [btrfs] [27175.316548] split_leaf+0x130/0x610 [btrfs] [27175.317390] btrfs_search_slot+0x94d/0x9a0 [btrfs] [27175.318235] btrfs_insert_empty_items+0x67/0xc0 [btrfs] [27175.319087] alloc_reserved_file_extent+0x84/0x2c0 [btrfs] [27175.319938] __btrfs_run_delayed_refs+0x596/0x1150 [btrfs] [27175.320792] btrfs_run_delayed_refs+0xed/0x1b0 [btrfs] [27175.321643] delayed_ref_async_start+0x81/0x90 [btrfs] [27175.322491] normal_work_helper+0xd0/0x320 [btrfs] [27175.323328] ? move_linked_works+0x6e/0xa0 [27175.324160] process_one_work+0x191/0x370 [27175.324976] worker_thread+0x4f/0x3b0 [27175.325763] kthread+0xf8/0x130 [27175.326531] ? rescuer_thread+0x320/0x320 [27175.327284] ? kthread_create_worker_on_cpu+0x50/0x50 [27175.328027] ret_from_fork+0x35/0x40 [27175.328741] ---[ end trace 300a1b9f0ac30e26 ]--- Fix this by preventing the flushing of new blocks groups when splitting a leaf/node and when inserting a new root node for one of the trees modified by the flushing operation, similar to what is done when COWing a node/leaf from on of these trees. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383 Reported-by: Eli V CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/ctree.c | 78 ++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 50 insertions(+), 28 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index f64aad613727..5a6c39b44c84 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -968,6 +968,48 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, return 0; } +static struct extent_buffer *alloc_tree_block_no_bg_flush( + struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 parent_start, + const struct btrfs_disk_key *disk_key, + int level, + u64 hint, + u64 empty_size) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + struct extent_buffer *ret; + + /* + * If we are COWing a node/leaf from the extent, chunk, device or free + * space trees, make sure that we do not finish block group creation of + * pending block groups. We do this to avoid a deadlock. + * COWing can result in allocation of a new chunk, and flushing pending + * block groups (btrfs_create_pending_block_groups()) can be triggered + * when finishing allocation of a new chunk. Creation of a pending block + * group modifies the extent, chunk, device and free space trees, + * therefore we could deadlock with ourselves since we are holding a + * lock on an extent buffer that btrfs_create_pending_block_groups() may + * try to COW later. + * For similar reasons, we also need to delay flushing pending block + * groups when splitting a leaf or node, from one of those trees, since + * we are holding a write lock on it and its parent or when inserting a + * new root node for one of those trees. + */ + if (root == fs_info->extent_root || + root == fs_info->chunk_root || + root == fs_info->dev_root || + root == fs_info->free_space_root) + trans->can_flush_pending_bgs = false; + + ret = btrfs_alloc_tree_block(trans, root, parent_start, + root->root_key.objectid, disk_key, level, + hint, empty_size); + trans->can_flush_pending_bgs = true; + + return ret; +} + /* * does the dirty work in cow of a single block. The parent block (if * supplied) is updated to point to the new cow copy. The new buffer is marked @@ -1015,28 +1057,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, if ((root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && parent) parent_start = parent->start; - /* - * If we are COWing a node/leaf from the extent, chunk, device or free - * space trees, make sure that we do not finish block group creation of - * pending block groups. We do this to avoid a deadlock. - * COWing can result in allocation of a new chunk, and flushing pending - * block groups (btrfs_create_pending_block_groups()) can be triggered - * when finishing allocation of a new chunk. Creation of a pending block - * group modifies the extent, chunk, device and free space trees, - * therefore we could deadlock with ourselves since we are holding a - * lock on an extent buffer that btrfs_create_pending_block_groups() may - * try to COW later. - */ - if (root == fs_info->extent_root || - root == fs_info->chunk_root || - root == fs_info->dev_root || - root == fs_info->free_space_root) - trans->can_flush_pending_bgs = false; - - cow = btrfs_alloc_tree_block(trans, root, parent_start, - root->root_key.objectid, &disk_key, level, - search_start, empty_size); - trans->can_flush_pending_bgs = true; + cow = alloc_tree_block_no_bg_flush(trans, root, parent_start, &disk_key, + level, search_start, empty_size); if (IS_ERR(cow)) return PTR_ERR(cow); @@ -3345,8 +3367,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans, else btrfs_node_key(lower, &lower_key, 0); - c = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid, - &lower_key, level, root->node->start, 0); + c = alloc_tree_block_no_bg_flush(trans, root, 0, &lower_key, level, + root->node->start, 0); if (IS_ERR(c)) return PTR_ERR(c); @@ -3475,8 +3497,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans, mid = (c_nritems + 1) / 2; btrfs_node_key(c, &disk_key, mid); - split = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid, - &disk_key, level, c->start, 0); + split = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, level, + c->start, 0); if (IS_ERR(split)) return PTR_ERR(split); @@ -4260,8 +4282,8 @@ again: else btrfs_item_key(l, &disk_key, mid); - right = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid, - &disk_key, 0, l->start, 0); + right = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, 0, + l->start, 0); if (IS_ERR(right)) return PTR_ERR(right); -- cgit v1.2.3-58-ga151 From 302167c50b32e7fccc98994a91d40ddbbab04e52 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 24 Jan 2019 09:31:43 -0500 Subject: btrfs: don't end the transaction for delayed refs in throttle Previously callers to btrfs_end_transaction_throttle() would commit the transaction if there wasn't enough delayed refs space. This happens in relocation, and if the fs is relatively empty we'll run out of delayed refs space basically immediately, so we'll just be stuck in this loop of committing the transaction over and over again. This code existed because we didn't have a good feedback mechanism for running delayed refs, but with the delayed refs rsv we do now. Delete this throttling code and let the btrfs_start_transaction() in relocation deal with putting pressure on the delayed refs infrastructure. With this patch we no longer take 5 minutes to balance a metadata only fs. Qu has submitted a fstest to catch slow balance or excessive transaction commits. Steps to reproduce: * create subvolume * create many (eg. 16000) inlined files, of size 2KiB * iteratively snapshot and touch several files to trigger metadata updates * start balance -m Reported-by: Qu Wenruo Fixes: 64403612b73a ("btrfs: rework btrfs_check_space_for_delayed_refs") Signed-off-by: Josef Bacik [ add tags and steps to reproduce ] Signed-off-by: David Sterba --- fs/btrfs/transaction.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 127fa1535f58..f15cf46f1b9d 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -850,14 +850,6 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, btrfs_trans_release_chunk_metadata(trans); - if (lock && should_end_transaction(trans) && - READ_ONCE(cur_trans->state) == TRANS_STATE_RUNNING) { - spin_lock(&info->trans_lock); - if (cur_trans->state == TRANS_STATE_RUNNING) - cur_trans->state = TRANS_STATE_BLOCKED; - spin_unlock(&info->trans_lock); - } - if (lock && READ_ONCE(cur_trans->state) == TRANS_STATE_BLOCKED) { if (throttle) return btrfs_commit_transaction(trans); -- cgit v1.2.3-58-ga151 From 80ff00172407e0aad4b10b94ef0816fc3e7813cb Mon Sep 17 00:00:00 2001 From: Yao Liu Date: Mon, 28 Jan 2019 19:44:14 +0800 Subject: nfs: Fix NULL pointer dereference of dev_name There is a NULL pointer dereference of dev_name in nfs_parse_devname() The oops looks something like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 ... RIP: 0010:nfs_fs_mount+0x3b6/0xc20 [nfs] ... Call Trace: ? ida_alloc_range+0x34b/0x3d0 ? nfs_clone_super+0x80/0x80 [nfs] ? nfs_free_parsed_mount_data+0x60/0x60 [nfs] mount_fs+0x52/0x170 ? __init_waitqueue_head+0x3b/0x50 vfs_kern_mount+0x6b/0x170 do_mount+0x216/0xdc0 ksys_mount+0x83/0xd0 __x64_sys_mount+0x25/0x30 do_syscall_64+0x65/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fix this by adding a NULL check on dev_name Signed-off-by: Yao Liu Signed-off-by: Anna Schumaker --- fs/nfs/super.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs') diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 22ce3c8a2f46..0570391eaa16 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -1895,6 +1895,11 @@ static int nfs_parse_devname(const char *dev_name, size_t len; char *end; + if (unlikely(!dev_name || !*dev_name)) { + dfprintk(MOUNT, "NFS: device name not specified\n"); + return -EINVAL; + } + /* Is the host name protected with square brakcets? */ if (*dev_name == '[') { end = strchr(++dev_name, ']'); -- cgit v1.2.3-58-ga151 From ff9fb72bc07705c00795ca48631f7fffe24d2c6b Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 23 Jan 2019 11:28:14 +0100 Subject: debugfs: return error values, not NULL When an error happens, debugfs should return an error pointer value, not NULL. This will prevent the totally theoretical error where a debugfs call fails due to lack of memory, returning NULL, and that dentry value is then passed to another debugfs call, which would end up succeeding, creating a file at the root of the debugfs tree, but would then be impossible to remove (because you can not remove the directory NULL). So, to make everyone happy, always return errors, this makes the users of debugfs much simpler (they do not have to ever check the return value), and everyone can rest easy. Reported-by: Gary R Hook Reported-by: Heiko Carstens Reported-by: Masami Hiramatsu Reported-by: Michal Hocko Reported-by: Sebastian Andrzej Siewior Reported-by: Ulf Hansson Reviewed-by: Masami Hiramatsu Reviewed-by: Sebastian Andrzej Siewior Signed-off-by: Greg Kroah-Hartman --- fs/debugfs/inode.c | 39 ++++++++++++++++++++++----------------- 1 file changed, 22 insertions(+), 17 deletions(-) (limited to 'fs') diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 41ef452c1fcf..b16f8035b1af 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -254,8 +254,8 @@ MODULE_ALIAS_FS("debugfs"); * @parent: a pointer to the parent dentry of the file. * * This function will return a pointer to a dentry if it succeeds. If the file - * doesn't exist or an error occurs, %NULL will be returned. The returned - * dentry must be passed to dput() when it is no longer needed. + * doesn't exist or an error occurs, %ERR_PTR(-ERROR) will be returned. The + * returned dentry must be passed to dput() when it is no longer needed. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -265,17 +265,17 @@ struct dentry *debugfs_lookup(const char *name, struct dentry *parent) struct dentry *dentry; if (IS_ERR(parent)) - return NULL; + return parent; if (!parent) parent = debugfs_mount->mnt_root; dentry = lookup_one_len_unlocked(name, parent, strlen(name)); if (IS_ERR(dentry)) - return NULL; + return dentry; if (!d_really_is_positive(dentry)) { dput(dentry); - return NULL; + return ERR_PTR(-EINVAL); } return dentry; } @@ -324,7 +324,7 @@ static struct dentry *failed_creating(struct dentry *dentry) inode_unlock(d_inode(dentry->d_parent)); dput(dentry); simple_release_fs(&debugfs_mount, &debugfs_mount_count); - return NULL; + return ERR_PTR(-ENOMEM); } static struct dentry *end_creating(struct dentry *dentry) @@ -347,7 +347,7 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode, dentry = start_creating(name, parent); if (IS_ERR(dentry)) - return NULL; + return dentry; inode = debugfs_get_inode(dentry->d_sb); if (unlikely(!inode)) @@ -386,7 +386,8 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode, * This function will return a pointer to a dentry if it succeeds. This * pointer must be passed to the debugfs_remove() function when the file is * to be removed (no automatic cleanup happens if your module is unloaded, - * you are responsible here.) If an error occurs, %NULL will be returned. + * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be + * returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -464,7 +465,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_unsafe); * This function will return a pointer to a dentry if it succeeds. This * pointer must be passed to the debugfs_remove() function when the file is * to be removed (no automatic cleanup happens if your module is unloaded, - * you are responsible here.) If an error occurs, %NULL will be returned. + * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be + * returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -495,7 +497,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_size); * This function will return a pointer to a dentry if it succeeds. This * pointer must be passed to the debugfs_remove() function when the file is * to be removed (no automatic cleanup happens if your module is unloaded, - * you are responsible here.) If an error occurs, %NULL will be returned. + * you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) will be + * returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -506,7 +509,7 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) struct inode *inode; if (IS_ERR(dentry)) - return NULL; + return dentry; inode = debugfs_get_inode(dentry->d_sb); if (unlikely(!inode)) @@ -545,7 +548,7 @@ struct dentry *debugfs_create_automount(const char *name, struct inode *inode; if (IS_ERR(dentry)) - return NULL; + return dentry; inode = debugfs_get_inode(dentry->d_sb); if (unlikely(!inode)) @@ -581,8 +584,8 @@ EXPORT_SYMBOL(debugfs_create_automount); * This function will return a pointer to a dentry if it succeeds. This * pointer must be passed to the debugfs_remove() function when the symbolic * link is to be removed (no automatic cleanup happens if your module is - * unloaded, you are responsible here.) If an error occurs, %NULL will be - * returned. + * unloaded, you are responsible here.) If an error occurs, %ERR_PTR(-ERROR) + * will be returned. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -594,12 +597,12 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, struct inode *inode; char *link = kstrdup(target, GFP_KERNEL); if (!link) - return NULL; + return ERR_PTR(-ENOMEM); dentry = start_creating(name, parent); if (IS_ERR(dentry)) { kfree(link); - return NULL; + return dentry; } inode = debugfs_get_inode(dentry->d_sb); @@ -827,7 +830,9 @@ exit: if (dentry && !IS_ERR(dentry)) dput(dentry); unlock_rename(new_dir, old_dir); - return NULL; + if (IS_ERR(dentry)) + return dentry; + return ERR_PTR(-EINVAL); } EXPORT_SYMBOL_GPL(debugfs_rename); -- cgit v1.2.3-58-ga151 From 8fc75bed96bb94e23ca51bd9be4daf65c57697bf Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 29 Jan 2019 15:52:55 -0500 Subject: NFS: Fix up return value on fatal errors in nfs_page_async_flush() Ensure that we return the fatal error value that caused us to exit nfs_page_async_flush(). Fixes: c373fff7bd25 ("NFSv4: Don't special case "launder"") Signed-off-by: Trond Myklebust Cc: stable@vger.kernel.org # v4.12+ Reviewed-by: Benjamin Coddington Signed-off-by: Anna Schumaker --- fs/nfs/write.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'fs') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 5a0bbf917a32..f12cb31a41e5 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -621,11 +621,12 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, nfs_set_page_writeback(page); WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags)); - ret = 0; + ret = req->wb_context->error; /* If there is a fatal error that covers this write, just exit */ - if (nfs_error_is_fatal_on_server(req->wb_context->error)) + if (nfs_error_is_fatal_on_server(ret)) goto out_launder; + ret = 0; if (!nfs_pageio_add_request(pgio, req)) { ret = pgio->pg_error; /* @@ -635,9 +636,9 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, nfs_context_set_write_error(req->wb_context, ret); if (nfs_error_is_fatal_on_server(ret)) goto out_launder; - } + } else + ret = -EAGAIN; nfs_redirty_request(req); - ret = -EAGAIN; } else nfs_add_stats(page_file_mapping(page)->host, NFSIOS_WRITEPAGES, 1); -- cgit v1.2.3-58-ga151 From 58d15ed1203f4d858c339ea4d7dafa94bd2a56d3 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Tue, 29 Jan 2019 12:46:16 +1000 Subject: cifs: fix computation for MAX_SMB2_HDR_SIZE The size of the fixed part of the create response is 88 bytes not 56. Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/smb2pdu.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 7a2d0a2255e6..e9cc6775df21 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -84,8 +84,8 @@ #define NUMBER_OF_SMB2_COMMANDS 0x0013 -/* 4 len + 52 transform hdr + 64 hdr + 56 create rsp */ -#define MAX_SMB2_HDR_SIZE 0x00b0 +/* 52 transform hdr + 64 hdr + 88 create rsp */ +#define MAX_SMB2_HDR_SIZE 204 #define SMB2_PROTO_NUMBER cpu_to_le32(0x424d53fe) #define SMB2_TRANSFORM_PROTO_NUM cpu_to_le32(0x424d53fd) -- cgit v1.2.3-58-ga151 From c4627e66f73a28c5515b908c90c2bf7120086497 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Tue, 29 Jan 2019 12:46:17 +1000 Subject: cifs: limit amount of data we request for xattrs to CIFSMaxBufSize minus the various headers and blobs that will be part of the reply. or else we might trigger a session reconnect. Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/smb2ops.c | 4 +++- fs/cifs/smb2pdu.h | 15 +++++++++++++-- 2 files changed, 16 insertions(+), 3 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 153238fc4fa9..6f96e2292856 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -866,7 +866,9 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon, FILE_READ_EA, FILE_FULL_EA_INFORMATION, SMB2_O_INFO_FILE, - SMB2_MAX_EA_BUF, + CIFSMaxBufSize - + MAX_SMB2_CREATE_RESPONSE_SIZE - + MAX_SMB2_CLOSE_RESPONSE_SIZE, &rsp_iov, &buftype, cifs_sb); if (rc) { /* diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index e9cc6775df21..538e2299805f 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -85,6 +85,7 @@ #define NUMBER_OF_SMB2_COMMANDS 0x0013 /* 52 transform hdr + 64 hdr + 88 create rsp */ +#define SMB2_TRANSFORM_HEADER_SIZE 52 #define MAX_SMB2_HDR_SIZE 204 #define SMB2_PROTO_NUMBER cpu_to_le32(0x424d53fe) @@ -648,6 +649,13 @@ struct smb2_create_req { __u8 Buffer[0]; } __packed; +/* + * Maximum size of a SMB2_CREATE response is 64 (smb2 header) + + * 88 (fixed part of create response) + 520 (path) + 150 (contexts) + + * 2 bytes of padding. + */ +#define MAX_SMB2_CREATE_RESPONSE_SIZE 824 + struct smb2_create_rsp { struct smb2_sync_hdr sync_hdr; __le16 StructureSize; /* Must be 89 */ @@ -996,6 +1004,11 @@ struct smb2_close_req { __u64 VolatileFileId; /* opaque endianness */ } __packed; +/* + * Maximum size of a SMB2_CLOSE response is 64 (smb2 header) + 60 (data) + */ +#define MAX_SMB2_CLOSE_RESPONSE_SIZE 124 + struct smb2_close_rsp { struct smb2_sync_hdr sync_hdr; __le16 StructureSize; /* 60 */ @@ -1398,8 +1411,6 @@ struct smb2_file_link_info { /* encoding of request for level 11 */ char FileName[0]; /* Name to be assigned to new link */ } __packed; /* level 11 Set */ -#define SMB2_MAX_EA_BUF 65536 - struct smb2_file_full_ea_info { /* encoding of response for level 15 */ __le32 next_entry_offset; __u8 flags; -- cgit v1.2.3-58-ga151 From 9bda8723da2d55b1de833b98cf802b88006e5b69 Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Wed, 23 Jan 2019 17:12:09 -0800 Subject: CIFS: Fix possible oops and memory leaks in async IO Allocation of a page array for non-cached IO was separated from allocation of rdata and wdata structures and this introduced memory leaks and a possible null pointer dereference. This patch fixes these problems. Cc: Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/file.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'fs') diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 2c7689f3998d..659ce1b92c44 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2696,6 +2696,7 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from, rc = cifs_write_allocate_pages(wdata->pages, nr_pages); if (rc) { + kvfree(wdata->pages); kfree(wdata); add_credits_and_wake_if(server, credits, 0); break; @@ -2707,6 +2708,7 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from, if (rc) { for (i = 0; i < nr_pages; i++) put_page(wdata->pages[i]); + kvfree(wdata->pages); kfree(wdata); add_credits_and_wake_if(server, credits, 0); break; @@ -3386,8 +3388,12 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file, } rc = cifs_read_allocate_pages(rdata, npages); - if (rc) - goto error; + if (rc) { + kvfree(rdata->pages); + kfree(rdata); + add_credits_and_wake_if(server, credits, 0); + break; + } rdata->tailsz = PAGE_SIZE; } @@ -3407,7 +3413,6 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file, if (!rdata->cfile->invalidHandle || !(rc = cifs_reopen_file(rdata->cfile, true))) rc = server->ops->async_readv(rdata); -error: if (rc) { add_credits_and_wake_if(server, rdata->credits, 0); kref_put(&rdata->refcount, -- cgit v1.2.3-58-ga151 From 7d42e72fe8ee5ab70b1af843dd7d8615e6fb0abe Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Fri, 25 Jan 2019 11:38:53 -0800 Subject: CIFS: Fix trace command logging for SMB2 reads and writes Currently we log success once we send an async IO request to the server. Instead we need to analyse a response and then log success or failure for a particular command. Also fix argument list for read logging. Cc: # 4.18 Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/smb2pdu.c | 46 ++++++++++++++++++++++++++++++---------------- 1 file changed, 30 insertions(+), 16 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 2ff209ec4fab..4b5ab9c80cc3 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -3241,8 +3241,17 @@ smb2_readv_callback(struct mid_q_entry *mid) rdata->mr = NULL; } #endif - if (rdata->result) + if (rdata->result) { cifs_stats_fail_inc(tcon, SMB2_READ_HE); + trace_smb3_read_err(0 /* xid */, + rdata->cfile->fid.persistent_fid, + tcon->tid, tcon->ses->Suid, rdata->offset, + rdata->bytes, rdata->result); + } else + trace_smb3_read_done(0 /* xid */, + rdata->cfile->fid.persistent_fid, + tcon->tid, tcon->ses->Suid, + rdata->offset, rdata->got_bytes); queue_work(cifsiod_wq, &rdata->work); DeleteMidQEntry(mid); @@ -3317,13 +3326,11 @@ smb2_async_readv(struct cifs_readdata *rdata) if (rc) { kref_put(&rdata->refcount, cifs_readdata_release); cifs_stats_fail_inc(io_parms.tcon, SMB2_READ_HE); - trace_smb3_read_err(rc, 0 /* xid */, io_parms.persistent_fid, - io_parms.tcon->tid, io_parms.tcon->ses->Suid, - io_parms.offset, io_parms.length); - } else - trace_smb3_read_done(0 /* xid */, io_parms.persistent_fid, - io_parms.tcon->tid, io_parms.tcon->ses->Suid, - io_parms.offset, io_parms.length); + trace_smb3_read_err(0 /* xid */, io_parms.persistent_fid, + io_parms.tcon->tid, + io_parms.tcon->ses->Suid, + io_parms.offset, io_parms.length, rc); + } cifs_small_buf_release(buf); return rc; @@ -3367,10 +3374,11 @@ SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms, if (rc != -ENODATA) { cifs_stats_fail_inc(io_parms->tcon, SMB2_READ_HE); cifs_dbg(VFS, "Send error in read = %d\n", rc); + trace_smb3_read_err(xid, req->PersistentFileId, + io_parms->tcon->tid, ses->Suid, + io_parms->offset, io_parms->length, + rc); } - trace_smb3_read_err(rc, xid, req->PersistentFileId, - io_parms->tcon->tid, ses->Suid, - io_parms->offset, io_parms->length); free_rsp_buf(resp_buftype, rsp_iov.iov_base); return rc == -ENODATA ? 0 : rc; } else @@ -3459,8 +3467,17 @@ smb2_writev_callback(struct mid_q_entry *mid) wdata->mr = NULL; } #endif - if (wdata->result) + if (wdata->result) { cifs_stats_fail_inc(tcon, SMB2_WRITE_HE); + trace_smb3_write_err(0 /* no xid */, + wdata->cfile->fid.persistent_fid, + tcon->tid, tcon->ses->Suid, wdata->offset, + wdata->bytes, wdata->result); + } else + trace_smb3_write_done(0 /* no xid */, + wdata->cfile->fid.persistent_fid, + tcon->tid, tcon->ses->Suid, + wdata->offset, wdata->bytes); queue_work(cifsiod_wq, &wdata->work); DeleteMidQEntry(mid); @@ -3602,10 +3619,7 @@ smb2_async_writev(struct cifs_writedata *wdata, wdata->bytes, rc); kref_put(&wdata->refcount, release); cifs_stats_fail_inc(tcon, SMB2_WRITE_HE); - } else - trace_smb3_write_done(0 /* no xid */, req->PersistentFileId, - tcon->tid, tcon->ses->Suid, wdata->offset, - wdata->bytes); + } async_writev_out: cifs_small_buf_release(req); -- cgit v1.2.3-58-ga151 From 8e6e72aeceaaed5aeeb1cb43d3085de7ceb14f79 Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Sat, 26 Jan 2019 12:21:32 -0800 Subject: CIFS: Do not count -ENODATA as failure for query directory Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French CC: Stable --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 4b5ab9c80cc3..d858dc04fdc3 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -3845,8 +3845,8 @@ SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon, rsp->sync_hdr.Status == STATUS_NO_MORE_FILES) { srch_inf->endOfSearch = true; rc = 0; - } - cifs_stats_fail_inc(tcon, SMB2_QUERY_DIRECTORY_HE); + } else + cifs_stats_fail_inc(tcon, SMB2_QUERY_DIRECTORY_HE); goto qdir_exit; } -- cgit v1.2.3-58-ga151 From 082aaa8700415f6471ec9c5ef0c8307ca214989a Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Fri, 18 Jan 2019 15:54:34 -0800 Subject: CIFS: Do not consider -ENODATA as stat failure for reads When doing reads beyound the end of a file the server returns error STATUS_END_OF_FILE error which is mapped to -ENODATA. Currently we report it as a failure which confuses read stats. Change it to not consider -ENODATA as failure for stat purposes. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French CC: Stable --- fs/cifs/smb2pdu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index d858dc04fdc3..ef52d6642431 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -3241,7 +3241,7 @@ smb2_readv_callback(struct mid_q_entry *mid) rdata->mr = NULL; } #endif - if (rdata->result) { + if (rdata->result && rdata->result != -ENODATA) { cifs_stats_fail_inc(tcon, SMB2_READ_HE); trace_smb3_read_err(0 /* xid */, rdata->cfile->fid.persistent_fid, -- cgit v1.2.3-58-ga151 From 37ea7b630ae5cdea4e8ff381d9d23abfef5939e6 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 30 Jan 2019 12:37:35 +0100 Subject: debugfs: debugfs_lookup() should return NULL if not found Lots of callers of debugfs_lookup() were just checking NULL to see if the file/directory was found or not. By changing this in ff9fb72bc077 ("debugfs: return error values, not NULL") we caused some subsystems to easily crash. Fixes: ff9fb72bc077 ("debugfs: return error values, not NULL") Reported-by: syzbot+b382ba6a802a3d242790@syzkaller.appspotmail.com Reported-by: Tetsuo Handa Cc: Omar Sandoval Cc: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- fs/debugfs/inode.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index b16f8035b1af..29c68c5d44d5 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -254,8 +254,8 @@ MODULE_ALIAS_FS("debugfs"); * @parent: a pointer to the parent dentry of the file. * * This function will return a pointer to a dentry if it succeeds. If the file - * doesn't exist or an error occurs, %ERR_PTR(-ERROR) will be returned. The - * returned dentry must be passed to dput() when it is no longer needed. + * doesn't exist or an error occurs, %NULL will be returned. The returned + * dentry must be passed to dput() when it is no longer needed. * * If debugfs is not enabled in the kernel, the value -%ENODEV will be * returned. @@ -265,17 +265,17 @@ struct dentry *debugfs_lookup(const char *name, struct dentry *parent) struct dentry *dentry; if (IS_ERR(parent)) - return parent; + return NULL; if (!parent) parent = debugfs_mount->mnt_root; dentry = lookup_one_len_unlocked(name, parent, strlen(name)); if (IS_ERR(dentry)) - return dentry; + return NULL; if (!d_really_is_positive(dentry)) { dput(dentry); - return ERR_PTR(-EINVAL); + return NULL; } return dentry; } -- cgit v1.2.3-58-ga151 From 92900e5160a5444d47dd376bc40066b709fbb5a6 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 27 Jan 2019 04:58:00 +0000 Subject: btrfs: fix potential oops in device_list_add alloc_fs_devices() can return ERR_PTR(-ENOMEM), so dereferencing its result before the check for IS_ERR() is a bad idea. Fixes: d1a63002829a4 ("btrfs: add members to fs_devices to track fsid changes") Reviewed-by: Nikolay Borisov Reviewed-by: Anand Jain Signed-off-by: Al Viro Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3e4f8f88353e..15561926ab32 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -957,11 +957,11 @@ static noinline struct btrfs_device *device_list_add(const char *path, else fs_devices = alloc_fs_devices(disk_super->fsid, NULL); - fs_devices->fsid_change = fsid_change_in_progress; - if (IS_ERR(fs_devices)) return ERR_CAST(fs_devices); + fs_devices->fsid_change = fsid_change_in_progress; + mutex_lock(&fs_devices->device_list_mutex); list_add(&fs_devices->fs_list, &fs_uuids); -- cgit v1.2.3-58-ga151 From c7cc64a98512ffc41df86d14a414eb3b09bf7481 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Wed, 23 Jan 2019 17:09:16 +0100 Subject: btrfs: clean up pending block groups when transaction commit aborts The fstests generic/475 stresses transaction aborts and can reveal space accounting or use-after-free bugs regarding block goups. In this case the pending block groups that remain linked to the structures after transaction commit aborts in the middle. The corrupted slabs lead to failures in following tests, eg. generic/476 [ 8172.752887] BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 [ 8172.755799] #PF error: [normal kernel read fault] [ 8172.757571] PGD 661ae067 P4D 661ae067 PUD 3db8e067 PMD 0 [ 8172.759000] Oops: 0000 [#1] PREEMPT SMP [ 8172.760209] CPU: 0 PID: 39 Comm: kswapd0 Tainted: G W 5.0.0-rc2-default #408 [ 8172.762495] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014 [ 8172.765772] RIP: 0010:shrink_page_list+0x2f9/0xe90 [ 8172.770453] RSP: 0018:ffff967f00663b18 EFLAGS: 00010287 [ 8172.771184] RAX: 0000000000000000 RBX: ffff967f00663c20 RCX: 0000000000000000 [ 8172.772850] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8c0620ab20e0 [ 8172.774629] RBP: ffff967f00663dd8 R08: 0000000000000000 R09: 0000000000000000 [ 8172.776094] R10: ffff8c0620ab22f8 R11: ffff8c063f772688 R12: ffff967f00663b78 [ 8172.777533] R13: ffff8c063f625600 R14: ffff8c063f625608 R15: dead000000000200 [ 8172.778886] FS: 0000000000000000(0000) GS:ffff8c063d400000(0000) knlGS:0000000000000000 [ 8172.780545] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8172.781787] CR2: 0000000000000058 CR3: 000000004e962000 CR4: 00000000000006f0 [ 8172.783547] Call Trace: [ 8172.784112] shrink_inactive_list+0x194/0x410 [ 8172.784747] shrink_node_memcg.constprop.85+0x3a5/0x6a0 [ 8172.785472] shrink_node+0x62/0x1e0 [ 8172.786011] balance_pgdat+0x216/0x460 [ 8172.786577] kswapd+0xe3/0x4a0 [ 8172.787085] ? finish_wait+0x80/0x80 [ 8172.787795] ? balance_pgdat+0x460/0x460 [ 8172.788799] kthread+0x116/0x130 [ 8172.789640] ? kthread_create_on_node+0x60/0x60 [ 8172.790323] ret_from_fork+0x24/0x30 [ 8172.794253] CR2: 0000000000000058 or accounting errors at umount time: [ 8159.537251] WARNING: CPU: 2 PID: 19031 at fs/btrfs/extent-tree.c:5987 btrfs_free_block_groups+0x3d5/0x410 [btrfs] [ 8159.543325] CPU: 2 PID: 19031 Comm: umount Tainted: G W 5.0.0-rc2-default #408 [ 8159.545472] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014 [ 8159.548155] RIP: 0010:btrfs_free_block_groups+0x3d5/0x410 [btrfs] [ 8159.554030] RSP: 0018:ffff967f079cbde8 EFLAGS: 00010206 [ 8159.555144] RAX: 0000000001000000 RBX: ffff8c06366cf800 RCX: 0000000000000000 [ 8159.556730] RDX: 0000000000000002 RSI: 0000000000000001 RDI: ffff8c06255ad800 [ 8159.558279] RBP: ffff8c0637ac0000 R08: 0000000000000001 R09: 0000000000000000 [ 8159.559797] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8c0637ac0108 [ 8159.561296] R13: ffff8c0637ac0158 R14: 0000000000000000 R15: dead000000000100 [ 8159.562852] FS: 00007f7f693b9fc0(0000) GS:ffff8c063d800000(0000) knlGS:0000000000000000 [ 8159.564839] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8159.566160] CR2: 00007f7f68fab7b0 CR3: 000000000aec7000 CR4: 00000000000006e0 [ 8159.567898] Call Trace: [ 8159.568597] close_ctree+0x17f/0x350 [btrfs] [ 8159.569628] generic_shutdown_super+0x64/0x100 [ 8159.570808] kill_anon_super+0x14/0x30 [ 8159.571857] btrfs_kill_super+0x12/0xa0 [btrfs] [ 8159.573063] deactivate_locked_super+0x29/0x60 [ 8159.574234] cleanup_mnt+0x3b/0x70 [ 8159.575176] task_work_run+0x98/0xc0 [ 8159.576177] exit_to_usermode_loop+0x83/0x90 [ 8159.577315] do_syscall_64+0x15b/0x180 [ 8159.578339] entry_SYSCALL_64_after_hwframe+0x49/0xbe This fix is based on 2 Josef's patches that used sideefects of btrfs_create_pending_block_groups, this fix introduces the helper that does what we need. CC: stable@vger.kernel.org # 4.4+ CC: Josef Bacik Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba --- fs/btrfs/transaction.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'fs') diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index f15cf46f1b9d..4ec2b660d014 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -1871,6 +1871,21 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, int err) kmem_cache_free(btrfs_trans_handle_cachep, trans); } +/* + * Release reserved delayed ref space of all pending block groups of the + * transaction and remove them from the list + */ +static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans) +{ + struct btrfs_fs_info *fs_info = trans->fs_info; + struct btrfs_block_group_cache *block_group, *tmp; + + list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) { + btrfs_delayed_refs_rsv_release(fs_info, 1); + list_del_init(&block_group->bg_list); + } +} + static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info *fs_info) { /* @@ -2262,6 +2277,7 @@ scrub_continue: btrfs_scrub_continue(fs_info); cleanup_transaction: btrfs_trans_release_metadata(trans); + btrfs_cleanup_pending_block_groups(trans); btrfs_trans_release_chunk_metadata(trans); trans->block_rsv = NULL; btrfs_warn(fs_info, "Skipping commit of aborted transaction."); -- cgit v1.2.3-58-ga151 From 532b618bdf237250d6d4566536d4b6ce3d0a31fe Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 30 Jan 2019 07:54:12 -0600 Subject: btrfs: On error always free subvol_name in btrfs_mount The subvol_name is allocated in btrfs_parse_subvol_options and is consumed and freed in mount_subvol. Add a free to the error paths that don't call mount_subvol so that it is guaranteed that subvol_name is freed when an error happens. Fixes: 312c89fbca06 ("btrfs: cleanup btrfs_mount() using btrfs_mount_root()") Cc: stable@vger.kernel.org # v4.19+ Reviewed-by: Nikolay Borisov Signed-off-by: "Eric W. Biederman" Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/super.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs') diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 368a5b9e6c13..74023786a735 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1677,6 +1677,7 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, flags | SB_RDONLY, device_name, data); if (IS_ERR(mnt_root)) { root = ERR_CAST(mnt_root); + kfree(subvol_name); goto out; } @@ -1686,12 +1687,14 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, if (error < 0) { root = ERR_PTR(error); mntput(mnt_root); + kfree(subvol_name); goto out; } } } if (IS_ERR(mnt_root)) { root = ERR_CAST(mnt_root); + kfree(subvol_name); goto out; } -- cgit v1.2.3-58-ga151 From 1dbd449c9943e3145148cc893c2461b72ba6fef0 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Wed, 30 Jan 2019 13:52:36 -0500 Subject: fs/dcache: Fix incorrect nr_dentry_unused accounting in shrink_dcache_sb() The nr_dentry_unused per-cpu counter tracks dentries in both the LRU lists and the shrink lists where the DCACHE_LRU_LIST bit is set. The shrink_dcache_sb() function moves dentries from the LRU list to a shrink list and subtracts the dentry count from nr_dentry_unused. This is incorrect as the nr_dentry_unused count will also be decremented in shrink_dentry_list() via d_shrink_del(). To fix this double decrement, the decrement in the shrink_dcache_sb() function is taken out. Fixes: 4e717f5c1083 ("list_lru: remove special case function list_lru_dispose_all." Cc: stable@kernel.org Signed-off-by: Waiman Long Reviewed-by: Dave Chinner Signed-off-by: Linus Torvalds --- fs/dcache.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/dcache.c b/fs/dcache.c index 2593153471cf..44e5652b2664 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1188,15 +1188,11 @@ static enum lru_status dentry_lru_isolate_shrink(struct list_head *item, */ void shrink_dcache_sb(struct super_block *sb) { - long freed; - do { LIST_HEAD(dispose); - freed = list_lru_walk(&sb->s_dentry_lru, + list_lru_walk(&sb->s_dentry_lru, dentry_lru_isolate_shrink, &dispose, 1024); - - this_cpu_sub(nr_dentry_unused, freed); shrink_dentry_list(&dispose); } while (list_lru_count(&sb->s_dentry_lru) > 0); } -- cgit v1.2.3-58-ga151 From af0c9af1b3f66052c369d08be3f60fa9a9559e48 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Wed, 30 Jan 2019 13:52:38 -0500 Subject: fs/dcache: Track & report number of negative dentries The current dentry number tracking code doesn't distinguish between positive & negative dentries. It just reports the total number of dentries in the LRU lists. As excessive number of negative dentries can have an impact on system performance, it will be wise to track the number of positive and negative dentries separately. This patch adds tracking for the total number of negative dentries in the system LRU lists and reports it in the 5th field in the /proc/sys/fs/dentry-state file. The number, however, does not include negative dentries that are in flight but not in the LRU yet as well as those in the shrinker lists which are on the way out anyway. The number of positive dentries in the LRU lists can be roughly found by subtracting the number of negative dentries from the unused count. Matthew Wilcox had confirmed that since the introduction of the dentry_stat structure in 2.1.60, the dummy array was there, probably for future extension. They were not replacements of pre-existing fields. So no sane applications that read the value of /proc/sys/fs/dentry-state will do dummy thing if the last 2 fields of the sysctl parameter are not zero. IOW, it will be safe to use one of the dummy array entry for negative dentry count. Signed-off-by: Waiman Long Signed-off-by: Linus Torvalds --- Documentation/sysctl/fs.txt | 26 ++++++++++++++++---------- fs/dcache.c | 32 ++++++++++++++++++++++++++++++++ include/linux/dcache.h | 7 ++++--- 3 files changed, 52 insertions(+), 13 deletions(-) (limited to 'fs') diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt index 819caf8ca05f..58649bd4fcfc 100644 --- a/Documentation/sysctl/fs.txt +++ b/Documentation/sysctl/fs.txt @@ -56,26 +56,32 @@ of any kernel data structures. dentry-state: -From linux/fs/dentry.c: +From linux/include/linux/dcache.h: -------------------------------------------------------------- -struct { +struct dentry_stat_t dentry_stat { int nr_dentry; int nr_unused; int age_limit; /* age in seconds */ int want_pages; /* pages requested by system */ - int dummy[2]; -} dentry_stat = {0, 0, 45, 0,}; --------------------------------------------------------------- - -Dentries are dynamically allocated and deallocated, and -nr_dentry seems to be 0 all the time. Hence it's safe to -assume that only nr_unused, age_limit and want_pages are -used. Nr_unused seems to be exactly what its name says. + int nr_negative; /* # of unused negative dentries */ + int dummy; /* Reserved for future use */ +}; +-------------------------------------------------------------- + +Dentries are dynamically allocated and deallocated. + +nr_dentry shows the total number of dentries allocated (active ++ unused). nr_unused shows the number of dentries that are not +actively used, but are saved in the LRU list for future reuse. + Age_limit is the age in seconds after which dcache entries can be reclaimed when memory is short and want_pages is nonzero when shrink_dcache_pages() has been called and the dcache isn't pruned yet. +nr_negative shows the number of unused dentries that are also +negative dentries which do not mapped to actual files. + ============================================================== dquot-max & dquot-nr: diff --git a/fs/dcache.c b/fs/dcache.c index 44e5652b2664..aac41adf4743 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -119,6 +119,7 @@ struct dentry_stat_t dentry_stat = { static DEFINE_PER_CPU(long, nr_dentry); static DEFINE_PER_CPU(long, nr_dentry_unused); +static DEFINE_PER_CPU(long, nr_dentry_negative); #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS) @@ -152,11 +153,22 @@ static long get_nr_dentry_unused(void) return sum < 0 ? 0 : sum; } +static long get_nr_dentry_negative(void) +{ + int i; + long sum = 0; + + for_each_possible_cpu(i) + sum += per_cpu(nr_dentry_negative, i); + return sum < 0 ? 0 : sum; +} + int proc_nr_dentry(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { dentry_stat.nr_dentry = get_nr_dentry(); dentry_stat.nr_unused = get_nr_dentry_unused(); + dentry_stat.nr_negative = get_nr_dentry_negative(); return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); } #endif @@ -317,6 +329,8 @@ static inline void __d_clear_type_and_inode(struct dentry *dentry) flags &= ~(DCACHE_ENTRY_TYPE | DCACHE_FALLTHRU); WRITE_ONCE(dentry->d_flags, flags); dentry->d_inode = NULL; + if (dentry->d_flags & DCACHE_LRU_LIST) + this_cpu_inc(nr_dentry_negative); } static void dentry_free(struct dentry *dentry) @@ -371,6 +385,11 @@ static void dentry_unlink_inode(struct dentry * dentry) * The per-cpu "nr_dentry_unused" counters are updated with * the DCACHE_LRU_LIST bit. * + * The per-cpu "nr_dentry_negative" counters are only updated + * when deleted from or added to the per-superblock LRU list, not + * from/to the shrink list. That is to avoid an unneeded dec/inc + * pair when moving from LRU to shrink list in select_collect(). + * * These helper functions make sure we always follow the * rules. d_lock must be held by the caller. */ @@ -380,6 +399,8 @@ static void d_lru_add(struct dentry *dentry) D_FLAG_VERIFY(dentry, 0); dentry->d_flags |= DCACHE_LRU_LIST; this_cpu_inc(nr_dentry_unused); + if (d_is_negative(dentry)) + this_cpu_inc(nr_dentry_negative); WARN_ON_ONCE(!list_lru_add(&dentry->d_sb->s_dentry_lru, &dentry->d_lru)); } @@ -388,6 +409,8 @@ static void d_lru_del(struct dentry *dentry) D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST); dentry->d_flags &= ~DCACHE_LRU_LIST; this_cpu_dec(nr_dentry_unused); + if (d_is_negative(dentry)) + this_cpu_dec(nr_dentry_negative); WARN_ON_ONCE(!list_lru_del(&dentry->d_sb->s_dentry_lru, &dentry->d_lru)); } @@ -418,6 +441,8 @@ static void d_lru_isolate(struct list_lru_one *lru, struct dentry *dentry) D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST); dentry->d_flags &= ~DCACHE_LRU_LIST; this_cpu_dec(nr_dentry_unused); + if (d_is_negative(dentry)) + this_cpu_dec(nr_dentry_negative); list_lru_isolate(lru, &dentry->d_lru); } @@ -426,6 +451,8 @@ static void d_lru_shrink_move(struct list_lru_one *lru, struct dentry *dentry, { D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST); dentry->d_flags |= DCACHE_SHRINK_LIST; + if (d_is_negative(dentry)) + this_cpu_dec(nr_dentry_negative); list_lru_isolate_move(lru, &dentry->d_lru, list); } @@ -1816,6 +1843,11 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode) WARN_ON(d_in_lookup(dentry)); spin_lock(&dentry->d_lock); + /* + * Decrement negative dentry count if it was in the LRU list. + */ + if (dentry->d_flags & DCACHE_LRU_LIST) + this_cpu_dec(nr_dentry_negative); hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry); raw_write_seqcount_begin(&dentry->d_seq); __d_set_inode_and_type(dentry, inode, add_flags); diff --git a/include/linux/dcache.h b/include/linux/dcache.h index ef4b70f64f33..60996e64c579 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -62,9 +62,10 @@ extern const struct qstr slash_name; struct dentry_stat_t { long nr_dentry; long nr_unused; - long age_limit; /* age in seconds */ - long want_pages; /* pages requested by system */ - long dummy[2]; + long age_limit; /* age in seconds */ + long want_pages; /* pages requested by system */ + long nr_negative; /* # of unused negative dentries */ + long dummy; /* Reserved for future use */ }; extern struct dentry_stat_t dentry_stat; -- cgit v1.2.3-58-ga151 From d339adc12a4f885b572c5412e4869af8939db854 Mon Sep 17 00:00:00 2001 From: Aurelien Aptel Date: Thu, 31 Jan 2019 13:46:07 +0100 Subject: CIFS: fix use-after-free of the lease keys The request buffers are freed right before copying the pointers. Use the func args instead which are identical and still valid. Simple reproducer (requires KASAN enabled) on a cifs mount: echo foo > foo ; tail -f foo & rm foo Cc: # 4.20 Fixes: 179e44d49c2f ("smb3: add tracepoint for sending lease break responses to server") Signed-off-by: Aurelien Aptel Signed-off-by: Steve French Reviewed-by: Paulo Alcantara --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index ef52d6642431..77b3aaa39b35 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -4441,8 +4441,8 @@ SMB2_lease_break(const unsigned int xid, struct cifs_tcon *tcon, rc = cifs_send_recv(xid, ses, &rqst, &resp_buf_type, flags, &rsp_iov); cifs_small_buf_release(req); - please_key_low = (__u64 *)req->LeaseKey; - please_key_high = (__u64 *)(req->LeaseKey+8); + please_key_low = (__u64 *)lease_key; + please_key_high = (__u64 *)(lease_key+8); if (rc) { cifs_stats_fail_inc(tcon, SMB2_OPLOCK_BREAK_HE); trace_smb3_lease_err(le32_to_cpu(lease_state), tcon->tid, -- cgit v1.2.3-58-ga151 From b9b9378b49030d1aeca2387660fcd1ac1f306cad Mon Sep 17 00:00:00 2001 From: Steve French Date: Tue, 29 Jan 2019 17:27:33 -0600 Subject: cifs: update internal module version number To 2.17 Signed-off-by: Steve French --- fs/cifs/cifsfs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index d1f9c2f3f575..7652551a1fc4 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -150,5 +150,5 @@ extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg); extern const struct export_operations cifs_export_ops; #endif /* CONFIG_CIFS_NFSD_EXPORT */ -#define CIFS_VERSION "2.16" +#define CIFS_VERSION "2.17" #endif /* _CIFSFS_H */ -- cgit v1.2.3-58-ga151 From e74c98ca2d6ae4376cc15fa2a22483430909d96b Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Wed, 30 Jan 2019 21:30:36 +0100 Subject: gfs2: Revert "Fix loop in gfs2_rbm_find" This reverts commit 2d29f6b96d8f80322ed2dd895bca590491c38d34. It turns out that the fix can lead to a ~20 percent performance regression in initial writes to the page cache according to iozone. Let's revert this for now to have more time for a proper fix. Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Andreas Gruenbacher Signed-off-by: Bob Peterson Signed-off-by: Linus Torvalds --- fs/gfs2/rgrp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index 831d7cb5a49c..17a8d3b43990 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -1780,9 +1780,9 @@ static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext, goto next_iter; } if (ret == -E2BIG) { - n += rbm->bii - initial_bii; rbm->bii = 0; rbm->offset = 0; + n += (rbm->bii - initial_bii); goto res_covered_end_of_rgrp; } return ret; -- cgit v1.2.3-58-ga151 From 1fde6f21d90f8ba5da3cb9c54ca991ed72696c43 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Fri, 1 Feb 2019 14:20:01 -0800 Subject: proc: fix /proc/net/* after setns(2) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit /proc entries under /proc/net/* can't be cached into dcache because setns(2) can change current net namespace. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: avoid vim miscolorization] [adobriyan@gmail.com: write test, add dummy ->d_revalidate hook: necessary if /proc/net/* is pinned at setns time] Link: http://lkml.kernel.org/r/20190108192350.GA12034@avx2 Link: http://lkml.kernel.org/r/20190107162336.GA9239@avx2 Fixes: 1da4d377f943fe4194ffb9fb9c26cc58fad4dd24 ("proc: revalidate misc dentries") Signed-off-by: Alexey Dobriyan Reported-by: Mateusz Stępień Reported-by: Ahmad Fatoum Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/generic.c | 4 +- fs/proc/internal.h | 1 + fs/proc/proc_net.c | 20 +++++ tools/testing/selftests/proc/.gitignore | 1 + tools/testing/selftests/proc/Makefile | 1 + tools/testing/selftests/proc/setns-dcache.c | 129 ++++++++++++++++++++++++++++ 6 files changed, 155 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/proc/setns-dcache.c (limited to 'fs') diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 8ae109429a88..e39bac94dead 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -256,7 +256,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, inode = proc_get_inode(dir->i_sb, de); if (!inode) return ERR_PTR(-ENOMEM); - d_set_d_op(dentry, &proc_misc_dentry_ops); + d_set_d_op(dentry, de->proc_dops); return d_splice_alias(inode, dentry); } read_unlock(&proc_subdir_lock); @@ -429,6 +429,8 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, INIT_LIST_HEAD(&ent->pde_openers); proc_set_user(ent, (*parent)->uid, (*parent)->gid); + ent->proc_dops = &proc_misc_dentry_ops; + out: return ent; } diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 5185d7f6a51e..95b14196f284 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -44,6 +44,7 @@ struct proc_dir_entry { struct completion *pde_unload_completion; const struct inode_operations *proc_iops; const struct file_operations *proc_fops; + const struct dentry_operations *proc_dops; union { const struct seq_operations *seq_ops; int (*single_show)(struct seq_file *, void *); diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c index d5e0fcb3439e..a7b12435519e 100644 --- a/fs/proc/proc_net.c +++ b/fs/proc/proc_net.c @@ -38,6 +38,22 @@ static struct net *get_proc_net(const struct inode *inode) return maybe_get_net(PDE_NET(PDE(inode))); } +static int proc_net_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + return 0; +} + +static const struct dentry_operations proc_net_dentry_ops = { + .d_revalidate = proc_net_d_revalidate, + .d_delete = always_delete_dentry, +}; + +static void pde_force_lookup(struct proc_dir_entry *pde) +{ + /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */ + pde->proc_dops = &proc_net_dentry_ops; +} + static int seq_open_net(struct inode *inode, struct file *file) { unsigned int state_size = PDE(inode)->state_size; @@ -90,6 +106,7 @@ struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode, p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; + pde_force_lookup(p); p->proc_fops = &proc_net_seq_fops; p->seq_ops = ops; p->state_size = state_size; @@ -133,6 +150,7 @@ struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; + pde_force_lookup(p); p->proc_fops = &proc_net_seq_fops; p->seq_ops = ops; p->state_size = state_size; @@ -181,6 +199,7 @@ struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode, p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; + pde_force_lookup(p); p->proc_fops = &proc_net_single_fops; p->single_show = show; return proc_register(parent, p); @@ -223,6 +242,7 @@ struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mo p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; + pde_force_lookup(p); p->proc_fops = &proc_net_single_fops; p->single_show = show; p->write = write; diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore index 82121a81681f..29bac5ef9a93 100644 --- a/tools/testing/selftests/proc/.gitignore +++ b/tools/testing/selftests/proc/.gitignore @@ -10,4 +10,5 @@ /proc-uptime-002 /read /self +/setns-dcache /thread-self diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile index 1c12c34cf85d..434d033ee067 100644 --- a/tools/testing/selftests/proc/Makefile +++ b/tools/testing/selftests/proc/Makefile @@ -14,6 +14,7 @@ TEST_GEN_PROGS += proc-uptime-001 TEST_GEN_PROGS += proc-uptime-002 TEST_GEN_PROGS += read TEST_GEN_PROGS += self +TEST_GEN_PROGS += setns-dcache TEST_GEN_PROGS += thread-self include ../lib.mk diff --git a/tools/testing/selftests/proc/setns-dcache.c b/tools/testing/selftests/proc/setns-dcache.c new file mode 100644 index 000000000000..60ab197a73fc --- /dev/null +++ b/tools/testing/selftests/proc/setns-dcache.c @@ -0,0 +1,129 @@ +/* + * Copyright © 2019 Alexey Dobriyan + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* + * Test that setns(CLONE_NEWNET) points to new /proc/net content even + * if old one is in dcache. + * + * FIXME /proc/net/unix is under CONFIG_UNIX which can be disabled. + */ +#undef NDEBUG +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static pid_t pid = -1; + +static void f(void) +{ + if (pid > 0) { + kill(pid, SIGTERM); + } +} + +int main(void) +{ + int fd[2]; + char _ = 0; + int nsfd; + + atexit(f); + + /* Check for priviledges and syscall availability straight away. */ + if (unshare(CLONE_NEWNET) == -1) { + if (errno == ENOSYS || errno == EPERM) { + return 4; + } + return 1; + } + /* Distinguisher between two otherwise empty net namespaces. */ + if (socket(AF_UNIX, SOCK_STREAM, 0) == -1) { + return 1; + } + + if (pipe(fd) == -1) { + return 1; + } + + pid = fork(); + if (pid == -1) { + return 1; + } + + if (pid == 0) { + if (unshare(CLONE_NEWNET) == -1) { + return 1; + } + + if (write(fd[1], &_, 1) != 1) { + return 1; + } + + pause(); + + return 0; + } + + if (read(fd[0], &_, 1) != 1) { + return 1; + } + + { + char buf[64]; + snprintf(buf, sizeof(buf), "/proc/%u/ns/net", pid); + nsfd = open(buf, O_RDONLY); + if (nsfd == -1) { + return 1; + } + } + + /* Reliably pin dentry into dcache. */ + (void)open("/proc/net/unix", O_RDONLY); + + if (setns(nsfd, CLONE_NEWNET) == -1) { + return 1; + } + + kill(pid, SIGTERM); + pid = 0; + + { + char buf[4096]; + ssize_t rv; + int fd; + + fd = open("/proc/net/unix", O_RDONLY); + if (fd == -1) { + return 1; + } + +#define S "Num RefCount Protocol Flags Type St Inode Path\n" + rv = read(fd, buf, sizeof(buf)); + + assert(rv == strlen(S)); + assert(memcmp(buf, S, strlen(S)) == 0); + } + + return 0; +} -- cgit v1.2.3-58-ga151 From c27d82f52f75fc9d8d9d40d120d2a96fdeeada5e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 1 Feb 2019 14:21:23 -0800 Subject: fs/drop_caches.c: avoid softlockups in drop_pagecache_sb() When superblock has lots of inodes without any pagecache (like is the case for /proc), drop_pagecache_sb() will iterate through all of them without dropping sb->s_inode_list_lock which can lead to softlockups (one of our customers hit this). Fix the problem by going to the slow path and doing cond_resched() in case the process needs rescheduling. Link: http://lkml.kernel.org/r/20190114085343.15011-1-jack@suse.cz Signed-off-by: Jan Kara Acked-by: Michal Hocko Reviewed-by: Andrew Morton Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/drop_caches.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/drop_caches.c b/fs/drop_caches.c index 82377017130f..d31b6c72b476 100644 --- a/fs/drop_caches.c +++ b/fs/drop_caches.c @@ -21,8 +21,13 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused) spin_lock(&sb->s_inode_list_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { spin_lock(&inode->i_lock); + /* + * We must skip inodes in unusual state. We may also skip + * inodes without pages but we deliberately won't in case + * we need to reschedule to avoid softlockups. + */ if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || - (inode->i_mapping->nrpages == 0)) { + (inode->i_mapping->nrpages == 0 && !need_resched())) { spin_unlock(&inode->i_lock); continue; } @@ -30,6 +35,7 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused) spin_unlock(&inode->i_lock); spin_unlock(&sb->s_inode_list_lock); + cond_resched(); invalidate_mapping_pages(inode->i_mapping, 0, -1); iput(toput_inode); toput_inode = inode; -- cgit v1.2.3-58-ga151 From 63ce5f552beb9bdb41546b3a26c4374758b21815 Mon Sep 17 00:00:00 2001 From: Pan Bian Date: Fri, 1 Feb 2019 14:21:26 -0800 Subject: autofs: drop dentry reference only when it is never used autofs_expire_run() calls dput(dentry) to drop the reference count of dentry. However, dentry is read via autofs_dentry_ino(dentry) after that. This may result in a use-free-bug. The patch drops the reference count of dentry only when it is never used. Link: http://lkml.kernel.org/r/154725122396.11260.16053424107144453867.stgit@pluto-themaw-net Signed-off-by: Pan Bian Signed-off-by: Ian Kent Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/autofs/expire.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/autofs/expire.c b/fs/autofs/expire.c index d441244b79df..28d9c2b1b3bb 100644 --- a/fs/autofs/expire.c +++ b/fs/autofs/expire.c @@ -596,7 +596,6 @@ int autofs_expire_run(struct super_block *sb, pkt.len = dentry->d_name.len; memcpy(pkt.name, dentry->d_name.name, pkt.len); pkt.name[pkt.len] = '\0'; - dput(dentry); if (copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire))) ret = -EFAULT; @@ -609,6 +608,8 @@ int autofs_expire_run(struct super_block *sb, complete_all(&ino->expire_complete); spin_unlock(&sbi->fs_lock); + dput(dentry); + return ret; } -- cgit v1.2.3-58-ga151 From f585b283e3f025754c45bbe7533fc6e5c4643700 Mon Sep 17 00:00:00 2001 From: Ian Kent Date: Fri, 1 Feb 2019 14:21:29 -0800 Subject: autofs: fix error return in autofs_fill_super() In autofs_fill_super() on error of get inode/make root dentry the return should be ENOMEM as this is the only failure case of the called functions. Link: http://lkml.kernel.org/r/154725123240.11260.796773942606871359.stgit@pluto-themaw-net Signed-off-by: Ian Kent Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/autofs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c index 0e8ea2d9a2bb..078992eee299 100644 --- a/fs/autofs/inode.c +++ b/fs/autofs/inode.c @@ -266,8 +266,10 @@ int autofs_fill_super(struct super_block *s, void *data, int silent) } root_inode = autofs_get_inode(s, S_IFDIR | 0755); root = d_make_root(root_inode); - if (!root) + if (!root) { + ret = -ENOMEM; goto fail_ino; + } pipe = NULL; root->d_fsdata = ino; -- cgit v1.2.3-58-ga151 From aa6ee4ab69293969867ab09b57546d226ace3d7a Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Fri, 1 Feb 2019 09:36:36 -0800 Subject: xfs: eof trim writeback mapping as soon as it is cached The cached writeback mapping is EOF trimmed to try and avoid races between post-eof block management and writeback that result in sending cached data to a stale location. The cached mapping is currently trimmed on the validation check, which leaves a race window between the time the mapping is cached and when it is trimmed against the current inode size. For example, if a new mapping is cached by delalloc conversion on a blocksize == page size fs, we could cycle various locks, perform memory allocations, etc. in the writeback codepath before the associated mapping is eventually trimmed to i_size. This leaves enough time for a post-eof truncate and file append before the cached mapping is trimmed. The former event essentially invalidates a range of the cached mapping and the latter bumps the inode size such the trim on the next writepage event won't trim all of the invalid blocks. fstest generic/464 reproduces this scenario occasionally and causes a lost writeback and stale delalloc blocks warning on inode inactivation. To work around this problem, trim the cached writeback mapping as soon as it is cached in addition to on subsequent validation checks. This is a minor tweak to tighten the race window as much as possible until a proper invalidation mechanism is available. Fixes: 40214d128e07 ("xfs: trim writepage mapping to within eof") Cc: # v4.14+ Signed-off-by: Brian Foster Reviewed-by: Allison Henderson Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_aops.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs') diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 338b9d9984e0..d9048bcea49c 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -449,6 +449,7 @@ xfs_map_blocks( } wpc->imap = imap; + xfs_trim_extent_eof(&wpc->imap, ip); trace_xfs_map_blocks_found(ip, offset, count, wpc->io_type, &imap); return 0; allocate_blocks: @@ -459,6 +460,7 @@ allocate_blocks: ASSERT(whichfork == XFS_COW_FORK || cow_fsb == NULLFILEOFF || imap.br_startoff + imap.br_blockcount <= cow_fsb); wpc->imap = imap; + xfs_trim_extent_eof(&wpc->imap, ip); trace_xfs_map_blocks_alloc(ip, offset, count, wpc->io_type, &imap); return 0; } -- cgit v1.2.3-58-ga151 From 465fa17f4a303d9fdff9eac4d45f91ece92e96ca Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Sun, 3 Feb 2019 14:03:06 -0800 Subject: xfs: end sync buffer I/O properly on shutdown error As of commit e339dd8d8b ("xfs: use sync buffer I/O for sync delwri queue submission"), the delwri submission code uses sync buffer I/O for sync delwri I/O. Instead of waiting on async I/O to unlock the buffer, it uses the underlying sync I/O completion mechanism. If delwri buffer submission fails due to a shutdown scenario, an error is set on the buffer and buffer completion never occurs. This can cause xfs_buf_delwri_submit() to deadlock waiting on a completion event. We could check the error state before waiting on such buffers, but that doesn't serialize against the case of an error set via a racing I/O completion. Instead, invoke I/O completion in the shutdown case regardless of buffer I/O type. Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_buf.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index eedc5e0156ff..1f9857e3630a 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -1536,8 +1536,7 @@ __xfs_buf_submit( xfs_buf_ioerror(bp, -EIO); bp->b_flags &= ~XBF_DONE; xfs_buf_stale(bp); - if (bp->b_flags & XBF_ASYNC) - xfs_buf_ioend(bp); + xfs_buf_ioend(bp); return -EIO; } -- cgit v1.2.3-58-ga151 From add46b3b021263c02d5a7080c58e5b459479fafd Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 3 Feb 2019 14:03:59 -0800 Subject: xfs: set buffer ops when repair probes for btree type In xrep_findroot_block, we work out the btree type and correctness of a given block by calling different btree verifiers on root block candidates. However, we leave the NULL b_ops while ->verify_read validates the block, which means that if the verifier calls xfs_buf_verifier_error it'll crash on the null b_ops. Fix it to set b_ops before calling the verifier and unsetting it if the verifier fails. Furthermore, improve the documentation around xfs_buf_ensure_ops, which is the function that is responsible for cleaning up the b_ops state of buffers that go through xrep_findroot_block but don't match anything. Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster --- fs/xfs/scrub/repair.c | 11 ++++++++--- fs/xfs/xfs_buf.c | 16 ++++++++++++++++ 2 files changed, 24 insertions(+), 3 deletions(-) (limited to 'fs') diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c index 1c8eecfe52b8..6acf1bfa0bfe 100644 --- a/fs/xfs/scrub/repair.c +++ b/fs/xfs/scrub/repair.c @@ -768,18 +768,23 @@ xrep_findroot_block( if (!uuid_equal(&btblock->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid)) goto out; + /* + * Read verifiers can reference b_ops, so we set the pointer + * here. If the verifier fails we'll reset the buffer state + * to what it was before we touched the buffer. + */ + bp->b_ops = fab->buf_ops; fab->buf_ops->verify_read(bp); if (bp->b_error) { + bp->b_ops = NULL; bp->b_error = 0; goto out; } /* * Some read verifiers will (re)set b_ops, so we must be - * careful not to blow away any such assignment. + * careful not to change b_ops after running the verifier. */ - if (!bp->b_ops) - bp->b_ops = fab->buf_ops; } /* diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 1f9857e3630a..4f5f2ff3f70f 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -776,10 +776,26 @@ _xfs_buf_read( } /* + * Set buffer ops on an unchecked buffer and validate it, if possible. + * * If the caller passed in an ops structure and the buffer doesn't have ops * assigned, set the ops and use them to verify the contents. If the contents * cannot be verified, we'll clear XBF_DONE. We assume the buffer has no * recorded errors and is already in XBF_DONE state. + * + * Under normal operations, every in-core buffer must have buffer ops assigned + * to them when the buffer is read in from disk so that we can validate the + * metadata. + * + * However, there are two scenarios where one can encounter in-core buffers + * that don't have buffer ops. The first is during log recovery of buffers on + * a V4 filesystem, though these buffers are purged at the end of recovery. + * + * The other is online repair, which tries to match arbitrary metadata blocks + * with btree types in order to find the root. If online repair doesn't match + * the buffer with /any/ btree type, the buffer remains in memory in DONE state + * with no ops, and a subsequent read_buf call from elsewhere will not set the + * ops. This function helps us fix this situation. */ int xfs_buf_ensure_ops( -- cgit v1.2.3-58-ga151 From e3fdc89ca47ef34dfb6fd5101fec084c3dba5486 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 21 Jan 2019 15:58:38 -0500 Subject: nfsd: Fix error return values for nfsd4_clone_file_range() If the parameter 'count' is non-zero, nfsd4_clone_file_range() will currently clobber all errors returned by vfs_clone_file_range() and replace them with EINVAL. Fixes: 42ec3d4c0218 ("vfs: make remap_file_range functions take and...") Signed-off-by: Trond Myklebust Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: J. Bruce Fields --- fs/nfsd/vfs.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 9824e32b2f23..7dc98e14655d 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -557,9 +557,11 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, loff_t cloned; cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0); + if (cloned < 0) + return nfserrno(cloned); if (count && cloned != count) - cloned = -EINVAL; - return nfserrno(cloned < 0 ? cloned : 0); + return nfserrno(-EINVAL); + return 0; } ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst, -- cgit v1.2.3-58-ga151