| Message ID | 1364410111-29418-1-git-send-email-geert@linux-m68k.org |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, 2013-03-27 at 19:48 +0100, Geert Uytterhoeven wrote: > On m68k, gcc tries to be smart and turns > > strncat(name, "%d", 2); > > into a call to strlen() and a 16-bit store, causing a link failure, > as arch/m68k/include/asm/string.h provides strlen() using a macro: > > ERROR: "strlen" [net/ipv4/ip_tunnel.ko] undefined! Perhaps you should fix the string library for m68k, then! > Use strlcat() instead to avoid this, which also allows to simplify the > check for buffer overflows. It looks like you're also fixing an off-by-one error: the maximum length of ops->kind will be IFNAMSIZ - 3 (just enough to add "%d" and the null terminator), rather than IFNAMSIZ - 4. Ben. > Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> > -- > Compile-tested only > > http://kisskb.ellerman.id.au/kisskb/buildresult/8462108/ > --- > net/ipv4/ip_tunnel.c | 5 ++--- > 1 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c > index 9d96b68..8dbe672 100644 > --- a/net/ipv4/ip_tunnel.c > +++ b/net/ipv4/ip_tunnel.c > @@ -284,12 +284,11 @@ static struct net_device *__ip_tunnel_create(struct net *net, > if (parms->name[0]) > strlcpy(name, parms->name, IFNAMSIZ); > else { > - if (strlen(ops->kind) + 3 >= IFNAMSIZ) { > + strlcpy(name, ops->kind, IFNAMSIZ); > + if (strlcat(name, "%d", IFNAMSIZ) >= IFNAMSIZ) { > err = -E2BIG; > goto failed; > } > - strlcpy(name, ops->kind, IFNAMSIZ); > - strncat(name, "%d", 2); > } > > ASSERT_RTNL();
From: Ben Hutchings <bhutchings@solarflare.com> Date: Wed, 27 Mar 2013 20:06:16 +0000 > On Wed, 2013-03-27 at 19:48 +0100, Geert Uytterhoeven wrote: >> On m68k, gcc tries to be smart and turns >> >> strncat(name, "%d", 2); >> >> into a call to strlen() and a 16-bit store, causing a link failure, >> as arch/m68k/include/asm/string.h provides strlen() using a macro: >> >> ERROR: "strlen" [net/ipv4/ip_tunnel.ko] undefined! > > Perhaps you should fix the string library for m68k, then! Right, this symbol really must be provided. You cannot merely provide inlines. The off-by-one error is seperate, but that should be fixed differently. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 9d96b68..8dbe672 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -284,12 +284,11 @@ static struct net_device *__ip_tunnel_create(struct net *net, if (parms->name[0]) strlcpy(name, parms->name, IFNAMSIZ); else { - if (strlen(ops->kind) + 3 >= IFNAMSIZ) { + strlcpy(name, ops->kind, IFNAMSIZ); + if (strlcat(name, "%d", IFNAMSIZ) >= IFNAMSIZ) { err = -E2BIG; goto failed; } - strlcpy(name, ops->kind, IFNAMSIZ); - strncat(name, "%d", 2); } ASSERT_RTNL();
On m68k, gcc tries to be smart and turns strncat(name, "%d", 2); into a call to strlen() and a 16-bit store, causing a link failure, as arch/m68k/include/asm/string.h provides strlen() using a macro: ERROR: "strlen" [net/ipv4/ip_tunnel.ko] undefined! Use strlcat() instead to avoid this, which also allows to simplify the check for buffer overflows. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> -- Compile-tested only http://kisskb.ellerman.id.au/kisskb/buildresult/8462108/ --- net/ipv4/ip_tunnel.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-)