diff options
| author | Askar Safin <safinaskar@zohomail.com> | 2025-08-25 18:12:33 +0000 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-09-02 10:40:43 +0200 |
| commit | 042a60680de43175eb4df0977ff04a4eba9da082 (patch) | |
| tree | bd038568e28dddc9ac5167b4e909663c9dd7c0c4 | |
| parent | 8ded1fde0827e52f3962d7931193f5a16d87a52c (diff) | |
openat2: don't trigger automounts with RESOLVE_NO_XDEV
openat2 had a bug: if we pass RESOLVE_NO_XDEV, then openat2
doesn't traverse through automounts, but may still trigger them.
(See the link for full bug report with reproducer.)
This commit fixes this bug.
Link: https://lore.kernel.org/linux-fsdevel/20250817075252.4137628-1-safinaskar@zohomail.com/
Fixes: fddb5d430ad9fa91b49b1 ("open: introduce openat2(2) syscall")
Reviewed-by: Aleksa Sarai <cyphar@cyphar.com>
Cc: stable@vger.kernel.org
Signed-off-by: Askar Safin <safinaskar@zohomail.com>
Link: https://lore.kernel.org/20250825181233.2464822-5-safinaskar@zohomail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
| -rw-r--r-- | fs/namei.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/namei.c b/fs/namei.c index f0ca6f8d0a5f..44856b70ea3b 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1449,6 +1449,10 @@ static int follow_automount(struct path *path, int *count, unsigned lookup_flags dentry->d_inode) return -EISDIR; + /* No need to trigger automounts if mountpoint crossing is disabled. */ + if (lookup_flags & LOOKUP_NO_XDEV) + return -EXDEV; + if (count && (*count)++ >= MAXSYMLINKS) return -ELOOP; @@ -1472,6 +1476,10 @@ static int __traverse_mounts(struct path *path, unsigned flags, bool *jumped, /* Allow the filesystem to manage the transit without i_rwsem * being held. */ if (flags & DCACHE_MANAGE_TRANSIT) { + if (lookup_flags & LOOKUP_NO_XDEV) { + ret = -EXDEV; + break; + } ret = path->dentry->d_op->d_manage(path, false); flags = smp_load_acquire(&path->dentry->d_flags); if (ret < 0) |