This is a note to let you know that I've just added the patch titled
net: nfc: llcp: Add lock when modifying device list
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-nfc-llcp-add-lock-when-modifying-device-list.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e4ee3654677648b7d7adb14a67c056b7507a0cdf
Author: Jeremy Cline <jeremy@xxxxxxxxxx>
Date: Fri Sep 8 19:58:53 2023 -0400
net: nfc: llcp: Add lock when modifying device list
[ Upstream commit dfc7f7a988dad34c3bf4c053124fb26aa6c5f916 ]
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@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=c1d0a03d305972dbbe14
Signed-off-by: Jeremy Cline <jeremy@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Fixes: 6709d4b7bc2e ("net: nfc: Fix use-after-free caused by nfc_llcp_find_local")
Link: https://lore.kernel.org/r/20230908235853.1319596-1-jeremy@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c
index ddfd159f64e13..b1107570eaee8 100644
--- a/net/nfc/llcp_core.c
+++ b/net/nfc/llcp_core.c
@@ -1646,7 +1646,9 @@ int nfc_llcp_register_device(struct nfc_dev *ndev)
timer_setup(&local->sdreq_timer, nfc_llcp_sdreq_timer, 0);
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;
}
