From: Anand Jain <anand.jain@xxxxxxxxxx>
commit 8cf96b409d9b3946ece58ced13f92d0f775b0442 upstream.
btrfs_ioctl_ino_to_path() frees the search path after the userspace copy
from the temp buffer @ipath->fspath. Which potentially can lead to a lock
splat warning.
Fix this by freeing the path before we copy it to userspace.
CC: stable@xxxxxxxxxxxxxxx # 4.19+
Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/ioctl.c | 2 ++
1 file changed, 2 insertions(+)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3892,6 +3892,8 @@ static long btrfs_ioctl_ino_to_path(stru
ipath->fspath->val[i] = rel_ptr;
}
+ btrfs_free_path(path);
+ path = NULL;
ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
ipath->fspath, size);
if (ret) {
