[PATCH net-next] ipv6: sit: Replace deprecated strcpy with strscpy

From: Thorsten Blum

Date: Thu Feb 26 2026 - 19:50:19 EST


strcpy() has been deprecated [1] because it performs no bounds checking
on the destination buffer, which can lead to buffer overflows. Replace
it with the safer strscpy(). Use the two-argument version of strscpy()
to copy 'parms->name' in ipip6_tunnel_locate().

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
---
net/ipv6/sit.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 439c8a1c6625..52f105315e1e 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -21,6 +21,7 @@
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
+#include <linux/string.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
@@ -256,9 +257,9 @@ static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
if (parms->name[0]) {
if (!dev_valid_name(parms->name))
goto failed;
- strscpy(name, parms->name, IFNAMSIZ);
+ strscpy(name, parms->name);
} else {
- strcpy(name, "sit%d");
+ strscpy(name, "sit%d");
}
dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
ipip6_tunnel_setup);
@@ -275,7 +276,7 @@ static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
goto failed_free;

if (!parms->name[0])
- strcpy(parms->name, dev->name);
+ strscpy(parms->name, dev->name);

return nt;

@@ -1442,7 +1443,7 @@ static int ipip6_tunnel_init(struct net_device *dev)
int err;

tunnel->dev = dev;
- strcpy(tunnel->parms.name, dev->name);
+ strscpy(tunnel->parms.name, dev->name);

ipip6_tunnel_bind_dev(dev);

@@ -1863,7 +1864,7 @@ static int __net_init sit_init_net(struct net *net)
ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);

- strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
+ strscpy(t->parms.name, sitn->fb_tunnel_dev->name);
return 0;

err_reg_dev:
--
Thorsten Blum <thorsten.blum@xxxxxxxxx>
GPG: 1D60 735E 8AEF 3BE4 73B6 9D84 7336 78FD 8DFE EAD4