From: Phil Sutter <phil@nwl.cc>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: netdev@vger.kernel.org
Subject: [iproute PATCH v2 1/3] ip{6,}tunnel: Avoid copying user-supplied interface name around
Date: Tue, 26 Sep 2017 18:35:46 +0200 [thread overview]
Message-ID: <20170926163548.24347-2-phil@nwl.cc> (raw)
In-Reply-To: <20170926163548.24347-1-phil@nwl.cc>
In both files' parse_args() functions as well as in iptunnel's do_prl()
and do_6rd() functions, a user-supplied 'dev' parameter is uselessly
copied into a temporary buffer before passing it to ll_name_to_index()
or copying into a struct ifreq. Avoid this by just caching the argv
pointer value until the later lookup/strcpy.
Signed-off-by: Phil Sutter <phil@nwl.cc>
---
ip/ip6tunnel.c | 6 +++---
ip/iptunnel.c | 22 +++++++++-------------
2 files changed, 12 insertions(+), 16 deletions(-)
diff --git a/ip/ip6tunnel.c b/ip/ip6tunnel.c
index b4a7def144226..c12d700e74189 100644
--- a/ip/ip6tunnel.c
+++ b/ip/ip6tunnel.c
@@ -136,7 +136,7 @@ static void print_tunnel(struct ip6_tnl_parm2 *p)
static int parse_args(int argc, char **argv, int cmd, struct ip6_tnl_parm2 *p)
{
int count = 0;
- char medium[IFNAMSIZ] = {};
+ const char *medium = NULL;
while (argc > 0) {
if (strcmp(*argv, "mode") == 0) {
@@ -180,7 +180,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip6_tnl_parm2 *p)
memcpy(&p->laddr, &laddr.data, sizeof(p->laddr));
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
- strncpy(medium, *argv, IFNAMSIZ - 1);
+ medium = *argv;
} else if (strcmp(*argv, "encaplimit") == 0) {
NEXT_ARG();
if (strcmp(*argv, "none") == 0) {
@@ -285,7 +285,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip6_tnl_parm2 *p)
count++;
argc--; argv++;
}
- if (medium[0]) {
+ if (medium) {
p->link = ll_name_to_index(medium);
if (p->link == 0) {
fprintf(stderr, "Cannot find device \"%s\"\n", medium);
diff --git a/ip/iptunnel.c b/ip/iptunnel.c
index 105d0f5576f1a..0acfd0793d3cd 100644
--- a/ip/iptunnel.c
+++ b/ip/iptunnel.c
@@ -60,7 +60,7 @@ static void set_tunnel_proto(struct ip_tunnel_parm *p, int proto)
static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
{
int count = 0;
- char medium[IFNAMSIZ] = {};
+ const char *medium = NULL;
int isatap = 0;
memset(p, 0, sizeof(*p));
@@ -139,7 +139,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
p->iph.saddr = htonl(INADDR_ANY);
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
- strncpy(medium, *argv, IFNAMSIZ - 1);
+ medium = *argv;
} else if (strcmp(*argv, "ttl") == 0 ||
strcmp(*argv, "hoplimit") == 0 ||
strcmp(*argv, "hlim") == 0) {
@@ -216,7 +216,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
}
}
- if (medium[0]) {
+ if (medium) {
p->link = ll_name_to_index(medium);
if (p->link == 0) {
fprintf(stderr, "Cannot find device \"%s\"\n", medium);
@@ -465,9 +465,8 @@ static int do_prl(int argc, char **argv)
{
struct ip_tunnel_prl p = {};
int count = 0;
- int devname = 0;
int cmd = 0;
- char medium[IFNAMSIZ] = {};
+ const char *medium = NULL;
while (argc > 0) {
if (strcmp(*argv, "prl-default") == 0) {
@@ -488,8 +487,7 @@ static int do_prl(int argc, char **argv)
count++;
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
- strncpy(medium, *argv, IFNAMSIZ-1);
- devname++;
+ medium = *argv;
} else {
fprintf(stderr,
"Invalid PRL parameter \"%s\"\n", *argv);
@@ -502,7 +500,7 @@ static int do_prl(int argc, char **argv)
}
argc--; argv++;
}
- if (devname == 0) {
+ if (!medium) {
fprintf(stderr, "Must specify device\n");
exit(-1);
}
@@ -513,9 +511,8 @@ static int do_prl(int argc, char **argv)
static int do_6rd(int argc, char **argv)
{
struct ip_tunnel_6rd ip6rd = {};
- int devname = 0;
int cmd = 0;
- char medium[IFNAMSIZ] = {};
+ const char *medium = NULL;
inet_prefix prefix;
while (argc > 0) {
@@ -537,8 +534,7 @@ static int do_6rd(int argc, char **argv)
cmd = SIOCDEL6RD;
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
- strncpy(medium, *argv, IFNAMSIZ-1);
- devname++;
+ medium = *argv;
} else {
fprintf(stderr,
"Invalid 6RD parameter \"%s\"\n", *argv);
@@ -546,7 +542,7 @@ static int do_6rd(int argc, char **argv)
}
argc--; argv++;
}
- if (devname == 0) {
+ if (!medium) {
fprintf(stderr, "Must specify device\n");
exit(-1);
}
--
2.13.1
next prev parent reply other threads:[~2017-09-26 16:36 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-26 16:35 [iproute PATCH v2 0/3] Check user supplied interface name lengths Phil Sutter
2017-09-26 16:35 ` Phil Sutter [this message]
2017-09-26 16:35 ` [iproute PATCH v2 2/3] tc: flower: No need to cache indev arg Phil Sutter
2017-09-26 16:35 ` [iproute PATCH v2 3/3] Check user supplied interface name lengths Phil Sutter
2017-09-27 7:42 ` [iproute PATCH v2 0/3] " Stephen Hemminger
2017-09-27 16:05 ` Phil Sutter
2017-09-29 17:31 ` Stephen Hemminger
2017-10-02 10:18 ` Phil Sutter
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