Commit 77a06c33a22d ("eventfs: Test for ei->is_freed when accessing
ei->dentry") added another check, testing if the parent was freed after
we released the mutex. If so, the function returns NULL. However, all
callers expect it to either return a valid pointer or an error pointer,
at least since commit 5264a2f4bb3b ("tracing: Fix a NULL vs IS_ERR() bug
in event_subsystem_dir()"). Returning NULL will therefore fail the error
condition check in the caller.
Fix this by substituting the NULL return value with a fitting error
pointer.
Fixes: 77a06c33a22d ("eventfs: Test for ei->is_freed when accessing ei->dentry")
Reviewed-by: Dan Carpenter <dan.carpen...@linaro.org>
Reviewed-by: Ajay Kaher <ajay.ka...@broadcom.com>
Signed-off-by: Mathias Krause <mini...@grsecurity.net>
---
v2: send as a separate patch, picking up review tags from Dan and Ajay
fs/tracefs/event_inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c
index 5d88c184f0fc..a9c28a1d5dc8 100644
--- a/fs/tracefs/event_inode.c
+++ b/fs/tracefs/event_inode.c
@@ -736,7 +736,7 @@ struct eventfs_inode *eventfs_create_dir(const char *name,
struct eventfs_inode
/* Was the parent freed? */
if (list_empty(&ei->list)) {
cleanup_ei(ei);
- ei = NULL;
+ ei = ERR_PTR(-EBUSY);
}
return ei;
}
--
2.43.0
