jsauer/torvalds-linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-01-11 17:10:13 +00:00
Code

landlock: fix splats from iput() after it started calling might_sleep()

Browse Source 
At this point it is guaranteed this is not the last reference.

However, a recent addition of might_sleep() at top of iput() started
generating false-positives as it was executing for all values.

Remedy the problem by using the newly introduced iput_not_last().

Reported-by: syzbot+12479ae15958fc3f54ec@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68d32659.a70a0220.4f78.0012.GAE@google.com/
Fixes: 2ef435a872ab ("fs: add might_sleep() annotation to iput() and more")
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251105212025.807549-2-mjguzik@gmail.com
Reviewed-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Mateusz Guzik 2025-11-05 22:20:25 +01:00 committed by Christian Brauner
parent 1274162464
commit 56325e8c68
No known key found for this signature in database
GPG Key ID: 91C61BC06578DCA2
1 changed files with 3 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
security/landlock/fs.c
View File

@ -1335,11 +1335,10 @@ static void hook_sb_delete(struct super_block *const sb)
* At this point, we own the ihold() reference that was
* originally set up by get_inode_object() and the
* __iget() reference that we just set in this loop
* walk. Therefore the following call to iput() will
* not sleep nor drop the inode because there is now at
* least two references to it.
* walk. Therefore there are at least two references
* on the inode.
*/
iput(inode);
iput_not_last(inode);
} else {
spin_unlock(&object->lock);
rcu_read_unlock();