| Message ID | 20240414003434.2659-1-danny@orbstack.dev (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fuse: fix leaked ENOSYS error on first statx call | expand |
On Sun, 14 Apr 2024 at 02:34, Danny Lin <danny@orbstack.dev> wrote: > > FUSE attempts to detect server support for statx by trying it once and > setting no_statx=1 if it fails with ENOSYS, but consider the following > scenario: > > - Userspace (e.g. sh) calls stat() on a file > * succeeds > - Userspace (e.g. lsd) calls statx(BTIME) on the same file > - request_mask = STATX_BASIC_STATS | STATX_BTIME > - first pass: sync=true due to differing cache_mask > - statx fails and returns ENOSYS > - set no_statx and retry > - retry sets mask = STATX_BASIC_STATS > - now mask == cache_mask; sync=false (time_before: still valid) > - so we take the "else if (stat)" path > - "err" is still ENOSYS from the failed statx call > > Fix this by zeroing "err" before retrying the failed call. Thanks, applied. Miklos
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index de452cdbf3cf..a63125ce70a4 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1362,6 +1362,7 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file, err = fuse_do_statx(inode, file, stat); if (err == -ENOSYS) { fc->no_statx = 1; + err = 0; goto retry; } } else {
FUSE attempts to detect server support for statx by trying it once and setting no_statx=1 if it fails with ENOSYS, but consider the following scenario: - Userspace (e.g. sh) calls stat() on a file * succeeds - Userspace (e.g. lsd) calls statx(BTIME) on the same file - request_mask = STATX_BASIC_STATS | STATX_BTIME - first pass: sync=true due to differing cache_mask - statx fails and returns ENOSYS - set no_statx and retry - retry sets mask = STATX_BASIC_STATS - now mask == cache_mask; sync=false (time_before: still valid) - so we take the "else if (stat)" path - "err" is still ENOSYS from the failed statx call Fix this by zeroing "err" before retrying the failed call. Fixes: d3045530bdd2 ("fuse: implement statx") Cc: stable@vger.kernel.org # v6.6 Signed-off-by: Danny Lin <danny@orbstack.dev> --- fs/fuse/dir.c | 1 + 1 file changed, 1 insertion(+)