From: Filipe Manana <fdmanana@suse.com>
Date: Wed, 6 Nov 2024 12:14:09 +0000 (+0000)
Subject: btrfs: fix warning on PTR_ERR() against NULL device at btrfs_control_ioctl()
X-Git-Tag: v6.13-rc1~213^2~3
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=2342d6595b608eec94187a17dc112dd4c2a812fa;p=linux-block.git

btrfs: fix warning on PTR_ERR() against NULL device at btrfs_control_ioctl()

Smatch complains about calling PTR_ERR() against a NULL pointer:

  fs/btrfs/super.c:2272 btrfs_control_ioctl() warn: passing zero to 'PTR_ERR'

Fix this by calling PTR_ERR() against the device pointer only if it
contains an error.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 7cd62307cd41..3381389ab93a 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -2254,7 +2254,10 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
 		device = btrfs_scan_one_device(vol->name, BLK_OPEN_READ, false);
 		if (IS_ERR_OR_NULL(device)) {
 			mutex_unlock(&uuid_mutex);
-			ret = PTR_ERR(device);
+			if (IS_ERR(device))
+				ret = PTR_ERR(device);
+			else
+				ret = 0;
 			break;
 		}
 		ret = !(device->fs_devices->num_devices ==