[PATCH v2] net: tun: replace strcpy with strscpy for ifr_name
From: Miguel García <hidden>
Date: 2025-08-11 20:33:44
Also in:
lkml
Subsystem:
networking drivers, the rest, tun/tap driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn, Jason Wang
Replace the strcpy() calls that copy the device name into ifr->ifr_name with strscpy() to avoid potential overflows and guarantee NULL termination. Destination is ifr->ifr_name (size IFNAMSIZ). Tested in QEMU (BusyBox rootfs): - Created TUN devices via TUNSETIFF helper - Set addresses and brought links up - Verified long interface names are safely truncated (IFNAMSIZ-1) v2: - Dropped third argument from strscpy(), inferred from field size. Signed-off-by: Miguel García <redacted> --- drivers/net/tun.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index f8c5e2fd04df..ad33b16224e2 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c@@ -2800,13 +2800,13 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (netif_running(tun->dev)) netif_tx_wake_all_queues(tun->dev); - strcpy(ifr->ifr_name, tun->dev->name); + strscpy(ifr->ifr_name, tun->dev->name); return 0; } static void tun_get_iff(struct tun_struct *tun, struct ifreq *ifr) { - strcpy(ifr->ifr_name, tun->dev->name); + strscpy(ifr->ifr_name, tun->dev->name); ifr->ifr_flags = tun_flags(tun);
--
2.34.1