From a4abc25157337f4e9db93c3e84ad5170cb72214d Mon Sep 17 00:00:00 2001
From: Jeremy Cline <jeremy@jcline.org>
Date: Fri, 8 Sep 2023 19:58:53 -0400
Subject: [PATCH 12/12] net: nfc: llcp: Add lock when modifying device list
Patch-mainline: v6.6-rc5
Git-commit: dfc7f7a988dad34c3bf4c053124fb26aa6c5f916
References: git-fixes CVE-2023-52524 bsc#1220927
The device list needs its associated lock held when modifying it, or the
list could become corrupted, as syzbot discovered.
Reported-and-tested-by: syzbot+c1d0a03d305972dbbe14@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c1d0a03d305972dbbe14
Signed-off-by: Jeremy Cline <jeremy@jcline.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Fixes: 6709d4b7bc2e ("net: nfc: Fix use-after-free caused by nfc_llcp_find_local")
Link: https://lore.kernel.org/r/20230908235853.1319596-1-jeremy@jcline.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
net/nfc/llcp_core.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c
index 93cdd33bde45..e1d74ce1f887 100644
--- a/net/nfc/llcp_core.c
+++ b/net/nfc/llcp_core.c
@@ -1651,7 +1651,9 @@ int nfc_llcp_register_device(struct nfc_dev *ndev)
local->sdreq_timer.function = nfc_llcp_sdreq_timer;
INIT_WORK(&local->sdreq_timeout_work, nfc_llcp_sdreq_timeout_work);
+ spin_lock(&llcp_devices_lock);
list_add(&local->list, &llcp_devices);
+ spin_unlock(&llcp_devices_lock);
return 0;
}
--
2.16.4