diff mbox series

cfg80211: fix debugfs rename crash

Message ID 20200525113816.fc4da3ec3d4b.Ica63a110679819eaa9fb3bc1b7437d96b1fd187d@changeid
State New
Headers show
Series cfg80211: fix debugfs rename crash | expand

Commit Message

Johannes Berg May 25, 2020, 9:38 a.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

Removing the "if (IS_ERR(dir)) dir = NULL;" check only works
if we adjust the remaining code to not rely on it being NULL.
Check IS_ERR_OR_NULL() before attempting to dereference it.

I'm not actually entirely sure this fixes the syzbot crash as
the kernel config indicates that they do have DEBUG_FS in the
kernel, but this is what I found when looking there.

Cc: stable@vger.kernel.org
Fixes: d82574a8e5a4 ("cfg80211: no need to check return value of debugfs_create functions")
Reported-by: syzbot+fd5332e429401bf42d18@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/wireless/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 341402b4f178..ce024440fa51 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -142,7 +142,7 @@  int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
 	if (result)
 		return result;
 
-	if (rdev->wiphy.debugfsdir)
+	if (!IS_ERR_OR_NULL(rdev->wiphy.debugfsdir))
 		debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
 			       rdev->wiphy.debugfsdir,
 			       rdev->wiphy.debugfsdir->d_parent, newname);