From a0e25f0a0d39d66c048d5dbac1e7ebaa6ec885d7 Mon Sep 17 00:00:00 2001 From: Dave Wysochanski Date: Sun, 3 Oct 2021 12:14:00 -0400 Subject: cachefiles: Fix oops with cachefiles_cull() due to NULL object When cachefiles_cull() calls cachefiles_bury_object(), it passes a NULL object. When this occurs, either trace_cachefiles_unlink() or trace_cachefiles_rename() may oops due to the NULL object. Check for NULL object in the tracepoint and if so, set debug_id to MAX_UINT as was done in 2908f5e101e3. The following oops was seen with xfstests generic/100. BUG: kernel NULL pointer dereference, address: 0000000000000010 ... RIP: 0010:trace_event_raw_event_cachefiles_unlink+0x4e/0xa0 [cachefiles] ... Call Trace: cachefiles_bury_object+0x242/0x430 [cachefiles] ? __vfs_removexattr_locked+0x10f/0x150 ? vfs_removexattr+0x51/0xd0 cachefiles_cull+0x84/0x120 [cachefiles] cachefiles_daemon_cull+0xd1/0x120 [cachefiles] cachefiles_daemon_write+0x158/0x190 [cachefiles] vfs_write+0xbc/0x260 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 The following oops was seen with xfstests generic/290. BUG: kernel NULL pointer dereference, address: 0000000000000010 ... RIP: 0010:trace_event_raw_event_cachefiles_rename+0x54/0xa0 [cachefiles] ... Call Trace: cachefiles_bury_object+0x35c/0x430 [cachefiles] cachefiles_cull+0x84/0x120 [cachefiles] cachefiles_daemon_cull+0xd1/0x120 [cachefiles] cachefiles_daemon_write+0x158/0x190 [cachefiles] vfs_write+0xbc/0x260 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 Fixes: 2908f5e101e3 ("fscache: Add a cookie debug ID and use that in traces") Signed-off-by: Dave Wysochanski Signed-off-by: David Howells Link: https://listman.redhat.com/archives/linux-cachefs/2021-October/msg00009.html --- include/trace/events/cachefiles.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h index 695bfdbfdcad..920b6a303d60 100644 --- a/include/trace/events/cachefiles.h +++ b/include/trace/events/cachefiles.h @@ -178,7 +178,7 @@ TRACE_EVENT(cachefiles_unlink, ), TP_fast_assign( - __entry->obj = obj->fscache.debug_id; + __entry->obj = obj ? obj->fscache.debug_id : UINT_MAX; __entry->de = de; __entry->why = why; ), @@ -205,7 +205,7 @@ TRACE_EVENT(cachefiles_rename, ), TP_fast_assign( - __entry->obj = obj->fscache.debug_id; + __entry->obj = obj ? obj->fscache.debug_id : UINT_MAX; __entry->de = de; __entry->to = to; __entry->why = why; -- cgit v1.2.3-58-ga151 From 330de47d14af0c3995db81cc03cf5ca683d94d81 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 26 Jul 2021 10:37:57 +0100 Subject: netfs: Fix READ/WRITE confusion when calling iov_iter_xarray() Fix netfs_clear_unread() to pass READ to iov_iter_xarray() instead of WRITE (the flag is about the operation accessing the buffer, not what sort of access it is doing to the buffer). Fixes: 3d3c95046742 ("netfs: Provide readahead and readpage netfs helpers") Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/162729351325.813557.9242842205308443901.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/162886603464.3940407.3790841170414793899.stgit@warthog.procyon.org.uk Link: https://lore.kernel.org/r/163239074602.1243337.14154704004485867017.stgit@warthog.procyon.org.uk --- fs/netfs/read_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c index 0b6cd3b8734c..994ec22d4040 100644 --- a/fs/netfs/read_helper.c +++ b/fs/netfs/read_helper.c @@ -150,7 +150,7 @@ static void netfs_clear_unread(struct netfs_read_subrequest *subreq) { struct iov_iter iter; - iov_iter_xarray(&iter, WRITE, &subreq->rreq->mapping->i_pages, + iov_iter_xarray(&iter, READ, &subreq->rreq->mapping->i_pages, subreq->start + subreq->transferred, subreq->len - subreq->transferred); iov_iter_zero(iov_iter_count(&iter), &iter); -- cgit v1.2.3-58-ga151 From 5c0522484eb54b90f2e46a5db8d7a4ff3ff86e5d Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 12 Aug 2021 23:08:54 +0100 Subject: afs: Fix afs_launder_page() to set correct start file position Fix afs_launder_page() to set the starting position of the StoreData RPC at the offset into the page at which the modified data starts instead of at the beginning of the page (the iov_iter is correctly offset). The offset got lost during the conversion to passing an iov_iter into afs_store_data(). Changes: ver #2: - Use page_offset() rather than manually calculating it[1]. Fixes: bd80d8a80e12 ("afs: Use ITER_XARRAY for writing") Signed-off-by: David Howells Reviewed-by: Jeffrey Altman cc: Marc Dionne cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/YST/0e92OdSH0zjg@casper.infradead.org/ [1] Link: https://lore.kernel.org/r/162880783179.3421678.7795105718190440134.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/162937512409.1449272.18441473411207824084.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/162981148752.1901565.3663780601682206026.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163005741670.2472992.2073548908229887941.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163221839087.3143591.14278359695763025231.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163292980654.4004896.7134735179887998551.stgit@warthog.procyon.org.uk/ # v2 --- fs/afs/write.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/afs/write.c b/fs/afs/write.c index 2dfe3b3a53d6..f24370f5c774 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -974,8 +974,7 @@ int afs_launder_page(struct page *page) iov_iter_bvec(&iter, WRITE, bv, 1, bv[0].bv_len); trace_afs_page_dirty(vnode, tracepoint_string("launder"), page); - ret = afs_store_data(vnode, &iter, (loff_t)page->index * PAGE_SIZE, - true); + ret = afs_store_data(vnode, &iter, page_offset(page) + f, true); } trace_afs_page_dirty(vnode, tracepoint_string("laundered"), page); -- cgit v1.2.3-58-ga151