From 33ab231f83cc12d0157711bbf84e180c3be7d7bc Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Mon, 3 Jul 2023 16:49:12 +0200 Subject: [PATCH] fs: don't assume arguments are non-NULL The helper is explicitly documented as locking zero, one, or two arguments. While all current callers do pass non-NULL arguments there's no need or requirement for them to do so according to the code and the unlock_two_nondirectories() helper is pretty clear about it as well. So only call WARN_ON_ONCE() if the checked inode is valid. Fixes: 2454ad83b90a ("fs: Restrict lock_two_nondirectories() to non-directory inodes") Reviewed-by: Jan Kara Cc: Jan Kara Message-Id: <20230703-vfs-rename-source-v1-2-37eebb29b65b@kernel.org> Signed-off-by: Christian Brauner --- fs/inode.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index d37fad91c8da..8fefb69e1f84 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1156,8 +1156,10 @@ lock: */ void lock_two_nondirectories(struct inode *inode1, struct inode *inode2) { - WARN_ON_ONCE(S_ISDIR(inode1->i_mode)); - WARN_ON_ONCE(S_ISDIR(inode2->i_mode)); + if (inode1) + WARN_ON_ONCE(S_ISDIR(inode1->i_mode)); + if (inode2) + WARN_ON_ONCE(S_ISDIR(inode2->i_mode)); lock_two_inodes(inode1, inode2, I_MUTEX_NORMAL, I_MUTEX_NONDIR2); } EXPORT_SYMBOL(lock_two_nondirectories);