[PATCH net-next] net/ipv6/ip6_vti: Use strscpy() to copy device name

[PATCH net-next] net/ipv6/ip6_vti: Use strscpy() to copy device name

[david.laight.linux]

From: David Laight <david.laight.linux@gmail.com>

Signed-off-by: David Laight <david.laight.linux@gmail.com>
---
This is one of a group of patches that remove potentially unbounded
strcpy() calls.

They are mostly replaced by strscpy() or, when strlen() has just been
called, with memcpy() (usually including the '\0').

Calls with copy string literals into arrays are left unchanged.
They are safe and easily detected as such.

The changes were made by getting the compiler to detect the calls and
then fixing the code by hand.

Note that all the changes are only compile tested.

Some Makefiles were changed to allow files to contain strcpy().
As well as 'difficult to fix' files, this included 'show' functions
as they really need to use sysfs_emit() or seq_printf().

All the patches are being sent individually to avoid very long cc lists.
Apologies for the terse commit messages and likely unexpected tags.
(There are about 100 patches in total.)

 net/ipv6/ip6_vti.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index ad5290be4dd6..c6cb756a1091 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -186,7 +186,7 @@ static int vti6_tnl_create2(struct net_device *dev)
 	if (err < 0)
 		goto out;
 
-	strcpy(t->parms.name, dev->name);
+	strscpy(t->parms.name, dev->name);
 
 	vti6_tnl_link(ip6n, t);
 
@@ -1161,7 +1161,7 @@ static int __net_init vti6_init_net(struct net *net)
 
 	t = netdev_priv(ip6n->fb_tnl_dev);
 
-	strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
+	strscpy(t->parms.name, ip6n->fb_tnl_dev->name);
 	return 0;
 
 err_register:
-- 
2.39.5

Re: [PATCH net-next] net/ipv6/ip6_vti: Use strscpy() to copy device name

[Jakub Kicinski]

On Sat,  6 Jun 2026 21:26:23 +0100 david.laight.linux@gmail.com wrote:
> Subject: [PATCH net-next] net/ipv6/ip6_vti: Use strscpy() to copy device name

Same comment as on the bonding patch goes for all the patches which
copy from dev->name. If dev->name is not properly terminated we have
more serious problems that this copy