This is a note to let you know that I've just added the patch titled net: bridge: Use array_size() helper in copy_to_user() to the 5.15-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-bridge-use-array_size-helper-in-copy_to_user.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 92e509ceb8674e14d64b8ade9bdcb5b476ae881c Author: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Date: Tue Sep 28 15:12:39 2021 -0500 net: bridge: Use array_size() helper in copy_to_user() [ Upstream commit 865bfb2affa8eff5182b29aa90803a2df4409834 ] Use array_size() helper instead of the open-coded version in copy_to_user(). These sorts of multiplication factors need to be wrapped in array_size(). Link: https://github.com/KSPP/linux/issues/160 Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/bridge/br_ioctl.c b/net/bridge/br_ioctl.c index 793b0db9d9a36..49c268871fc11 100644 --- a/net/bridge/br_ioctl.c +++ b/net/bridge/br_ioctl.c @@ -71,7 +71,8 @@ static int get_fdb_entries(struct net_bridge *br, void __user *userbuf, num = br_fdb_fillbuf(br, buf, maxnum, offset); if (num > 0) { - if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry))) + if (copy_to_user(userbuf, buf, + array_size(num, sizeof(struct __fdb_entry)))) num = -EFAULT; } kfree(buf); @@ -188,7 +189,7 @@ int br_dev_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user return -ENOMEM; get_port_ifindices(br, indices, num); - if (copy_to_user(argp, indices, num * sizeof(int))) + if (copy_to_user(argp, indices, array_size(num, sizeof(int)))) num = -EFAULT; kfree(indices); return num; @@ -336,7 +337,8 @@ static int old_deviceless(struct net *net, void __user *uarg) args[2] = get_bridge_ifindices(net, indices, args[2]); - ret = copy_to_user(uarg, indices, args[2]*sizeof(int)) + ret = copy_to_user(uarg, indices, + array_size(args[2], sizeof(int))) ? -EFAULT : args[2]; kfree(indices);