Hi,
On Sat, 1 Dec 2018, Qian Cai wrote:
> To make overflows as obvious as possible and to prevent code from blithely
> proceeding with a truncated string. This also has a side-effect to fix a
> compilation warning when using GCC 8.2.1.
>
> net/netfilter/ipset/ip_set_core.c: In function 'ip_set_sockfn_get':
> net/netfilter/ipset/ip_set_core.c:2027:3: warning: 'strncpy' writing 32
> bytes into a region of size 2 overflows the destination
> [-Wstringop-overflow=]
>
> Signed-off-by: Qian Cai <c...@gmx.us>
Patch is applied with a slight modification, see below:
> Changelog:
> * v2:
> - Released the lock for the error-path as well.
> * v1:
> - Checked the return value.
>
> net/netfilter/ipset/ip_set_core.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/net/netfilter/ipset/ip_set_core.c
> b/net/netfilter/ipset/ip_set_core.c
> index 1577f2f76060..33929fb645b6 100644
> --- a/net/netfilter/ipset/ip_set_core.c
> +++ b/net/netfilter/ipset/ip_set_core.c
> @@ -2024,9 +2024,11 @@ ip_set_sockfn_get(struct sock *sk, int optval, void
> __user *user, int *len)
> }
> nfnl_lock(NFNL_SUBSYS_IPSET);
> set = ip_set(inst, req_get->set.index);
> - strncpy(req_get->set.name, set ? set->name : "",
> - IPSET_MAXNAMELEN);
> + ret = strscpy(req_get->set.name, set ? set->name : "",
> + IPSET_MAXNAMELEN);
> nfnl_unlock(NFNL_SUBSYS_IPSET);
> + if (ret == -E2BIG)
I replaced the condition with
if (ret < 0)
so that it can handle future error codes from strscpy() as well.
> + goto done;
> goto copy;
> }
> default:
Best regards,
Jozsef
-
E-mail : kad...@blackhole.kfki.hu, kadlecsik.joz...@wigner.mta.hu
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