From: Darrick J. Wong darrick.wong@oracle.com
[ Upstream commit 1cb5deb5bc095c070c09a4540c45f9c9ba24be43 ]
If we decide that a directory free block is corrupt, we must take care not to leak a buffer pointer to the caller. After xfs_trans_brelse returns, the buffer can be freed or reused, which means that we have to set *bpp back to NULL.
Callers are supposed to notice the nonzero return value and not use the buffer pointer, but we should code more defensively, even if all current callers handle this situation correctly.
Fixes: de14c5f541e7 ("xfs: verify free block header fields") Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Dave Chinner dchinner@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/xfs/libxfs/xfs_dir2_node.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/fs/xfs/libxfs/xfs_dir2_node.c b/fs/xfs/libxfs/xfs_dir2_node.c index 705c4f5627582..99d5b2ed67f2e 100644 --- a/fs/xfs/libxfs/xfs_dir2_node.c +++ b/fs/xfs/libxfs/xfs_dir2_node.c @@ -210,6 +210,7 @@ __xfs_dir3_free_read( if (fa) { xfs_verifier_error(*bpp, -EFSCORRUPTED, fa); xfs_trans_brelse(tp, *bpp); + *bpp = NULL; return -EFSCORRUPTED; }