From f98ccd7d77210ff939bb2a8d854d2ff3619ed8d7 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 15 Jan 2025 18:55:43 +0900 Subject: [PATCH] dev: Acquire netdev_rename_lock before restoring dev->name in dev_change_name(). [ Upstream commit e361560a7912958ba3059f51e7dd21612d119169 ] The cited commit forgot to add netdev_rename_lock in one of the error paths in dev_change_name(). Let's hold netdev_rename_lock before restoring the old dev->name. Fixes: 0840556e5a3a ("net: Protect dev->name by seqlock.") Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20250115095545.52709-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/dev.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/core/dev.c b/net/core/dev.c index 1867a6a8d76d..9bdb8fe5ffaa 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1279,7 +1279,9 @@ int dev_change_name(struct net_device *dev, const char *newname) rollback: ret = device_rename(&dev->dev, dev->name); if (ret) { + write_seqlock_bh(&netdev_rename_lock); memcpy(dev->name, oldname, IFNAMSIZ); + write_sequnlock_bh(&netdev_rename_lock); WRITE_ONCE(dev->name_assign_type, old_assign_type); up_write(&devnet_rename_sem); return ret;