From cbd7ad29a5070a75dd076118ce7e400ce4b8d8d1 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Thu, 5 Aug 2021 11:29:02 +0300 Subject: [PATCH] net: bridge: fix ioctl old_deviceless bridge argument Commit ad2f99aedf8f ("net: bridge: move bridge ioctls out of .ndo_do_ioctl") changed the source of the argument copy in bridge's old_deviceless() from args[1] (user ptr to device name) to uarg (ptr to ioctl arguments) causing wrong device name to be used. Example (broken, bridge exists but is up): $ brctl delbr bridge bridge bridge doesn't exist; can't delete it Example (working): $ brctl delbr bridge bridge bridge is still up; can't delete it Fixes: ad2f99aedf8f ("net: bridge: move bridge ioctls out of .ndo_do_ioctl") Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/bridge/br_ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bridge/br_ioctl.c b/net/bridge/br_ioctl.c index 2f848de3e755..793b0db9d9a3 100644 --- a/net/bridge/br_ioctl.c +++ b/net/bridge/br_ioctl.c @@ -351,7 +351,7 @@ static int old_deviceless(struct net *net, void __user *uarg) if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) return -EPERM; - if (copy_from_user(buf, uarg, IFNAMSIZ)) + if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ)) return -EFAULT; buf[IFNAMSIZ-1] = 0;