Forwarded: [PATCH] batman-adv: avoid WARN_ON for orig_ifinfo allocation failure

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Subject: [PATCH] batman-adv: avoid WARN_ON for orig_ifinfo allocation failure
Author: kartikey406@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master



batadv_orig_ifinfo_new() returns NULL only when its GFP_ATOMIC
allocation fails, which is a normal runtime condition and not a bug.
batadv_v_ogm_forward() already handles this the same way, simply
checking for NULL without a WARN_ON.

Do the same in batadv_iv_ogm_update_seqnos() to avoid a spurious
WARN_ON splat when the allocation fails (e.g. under fault injection).

Fixes: 7351a4822d42 ("batman-adv: split out router from orig_node")
Reported-by: syzbot+a079f084653164a652d1@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a079f084653164a652d1
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
---
 net/batman-adv/bat_iv_ogm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 53fbdbbe8f4f..d8a6a0f64ce2 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1410,7 +1410,7 @@ batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 		return BATADV_NO_DUP;
 
 	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
-	if (WARN_ON(!orig_ifinfo)) {
+	if (!orig_ifinfo) {
 		batadv_orig_node_put(orig_node);
 		return 0;
 	}
-- 
2.43.0