diff options
| author | Filipe Manana <fdmanana@suse.com> | 2025-02-15 14:36:15 +0300 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2025-02-21 11:31:48 +0300 |
| commit | 59f37036bb7ab3d554c24abc856aabca01126414 (patch) | |
| tree | 5524649f231619054440a3e27d9c5f555c03e06c | |
| parent | 290237fde9491ca26cf4020bbf5a2b330452e7db (diff) | |
| download | linux-59f37036bb7ab3d554c24abc856aabca01126414.tar.xz | |
btrfs: fix use-after-free on inode when scanning root during em shrinking
At btrfs_scan_root() we are accessing the inode's root (and fs_info) in a
call to btrfs_fs_closing() after we have scheduled the inode for a delayed
iput, and that can result in a use-after-free on the inode in case the
cleaner kthread does the iput before we dereference the inode in the call
to btrfs_fs_closing().
Fix this by using the fs_info stored already in a local variable instead
of doing inode->root->fs_info.
Fixes: 102044384056 ("btrfs: make the extent map shrinker run asynchronously as a work queue job")
CC: stable@vger.kernel.org # 6.13+
Tested-by: Ivan Shapovalov <intelfx@intelfx.name>
Link: https://lore.kernel.org/linux-btrfs/0414d690ac5680d0d77dfc930606cdc36e42e12f.camel@intelfx.name/
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
| -rw-r--r-- | fs/btrfs/extent_map.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 67ce85ff0ae2..bee1b94a1049 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -1222,8 +1222,7 @@ static long btrfs_scan_root(struct btrfs_root *root, struct btrfs_em_shrink_ctx fs_info->em_shrinker_last_ino = btrfs_ino(inode); btrfs_add_delayed_iput(inode); - if (ctx->scanned >= ctx->nr_to_scan || - btrfs_fs_closing(inode->root->fs_info)) + if (ctx->scanned >= ctx->nr_to_scan || btrfs_fs_closing(fs_info)) break; cond_resched(); |