diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-11-16 09:30:13 -0600 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-11-16 09:30:13 -0600 |
| commit | 9b5f361ac4a923bf53ca8c0875509ef68c8958cd (patch) | |
| tree | 07edca4e552da466dab697ff1c8932ffa8679730 /fs | |
| parent | da5322e65940e4e8426613a8ff3d99a08b350a52 (diff) | |
| parent | ebacb81273599555a7a19f7754a1451206a5fc4f (diff) | |
Merge tag 'fuse-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
"A couple of fixes, all bound for -stable (i.e. not regressions in this
cycle)"
* tag 'fuse-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: fix use-after-free in fuse_direct_IO()
fuse: fix possibly missed wake-up after abort
fuse: fix leaked notify reply
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fuse/dev.c | 16 | ||||
| -rw-r--r-- | fs/fuse/file.c | 4 |
2 files changed, 15 insertions, 5 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index ae813e609932..a5e516a40e7a 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -165,9 +165,13 @@ static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background) static void fuse_drop_waiting(struct fuse_conn *fc) { - if (fc->connected) { - atomic_dec(&fc->num_waiting); - } else if (atomic_dec_and_test(&fc->num_waiting)) { + /* + * lockess check of fc->connected is okay, because atomic_dec_and_test() + * provides a memory barrier mached with the one in fuse_wait_aborted() + * to ensure no wake-up is missed. + */ + if (atomic_dec_and_test(&fc->num_waiting) && + !READ_ONCE(fc->connected)) { /* wake up aborters */ wake_up_all(&fc->blocked_waitq); } @@ -1768,8 +1772,10 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, req->in.args[1].size = total_len; err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique); - if (err) + if (err) { fuse_retrieve_end(fc, req); + fuse_put_request(fc, req); + } return err; } @@ -2219,6 +2225,8 @@ EXPORT_SYMBOL_GPL(fuse_abort_conn); void fuse_wait_aborted(struct fuse_conn *fc) { + /* matches implicit memory barrier in fuse_drop_waiting() */ + smp_mb(); wait_event(fc->blocked_waitq, atomic_read(&fc->num_waiting) == 0); } diff --git a/fs/fuse/file.c b/fs/fuse/file.c index cc2121b37bf5..b52f9baaa3e7 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2924,10 +2924,12 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter) } if (io->async) { + bool blocking = io->blocking; + fuse_aio_complete(io, ret < 0 ? ret : 0, -1); /* we have a non-extending, async request, so return */ - if (!io->blocking) + if (!blocking) return -EIOCBQUEUED; wait_for_completion(&wait); |