lkml.org 
[lkml]   [2011]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[12/87] netfilter: fix export secctx error handling
2.6.37-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Pablo Neira Ayuso <pablo@netfilter.org>

commit cba85b532e4aabdb97f44c18987d45141fd93faa upstream.

In 1ae4de0cdf855305765592647025bde55e85e451, the secctx was exported
via the /proc/net/netfilter/nf_conntrack and ctnetlink interfaces
instead of the secmark.

That patch introduced the use of security_secid_to_secctx() which may
return a non-zero value on error.

In one of my setups, I have NF_CONNTRACK_SECMARK enabled but no
security modules. Thus, security_secid_to_secctx() returns a negative
value that results in the breakage of the /proc and `conntrack -L'
outputs. To fix this, we skip the inclusion of secctx if the
aforementioned function fails.

This patch also fixes the dynamic netlink message size calculation
if security_secid_to_secctx() returns an error, since its logic is
also wrong.

This problem exists in Linux kernel >= 2.6.37.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c | 2 -
net/netfilter/nf_conntrack_netlink.c | 25 ++++++++++--------
net/netfilter/nf_conntrack_standalone.c | 2 -
3 files changed, 16 insertions(+), 13 deletions(-)

--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
@@ -97,7 +97,7 @@ static int ct_show_secctx(struct seq_fil

ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
if (ret)
- return ret;
+ return 0;

ret = seq_printf(s, "secctx=%s ", secctx);

--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -254,7 +254,7 @@ ctnetlink_dump_secctx(struct sk_buff *sk

ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
if (ret)
- return ret;
+ return 0;

ret = -1;
nest_secctx = nla_nest_start(skb, CTA_SECCTX | NLA_F_NESTED);
@@ -453,16 +453,22 @@ ctnetlink_counters_size(const struct nf_
;
}

-#ifdef CONFIG_NF_CONNTRACK_SECMARK
-static int ctnetlink_nlmsg_secctx_size(const struct nf_conn *ct)
+static inline int
+ctnetlink_secctx_size(const struct nf_conn *ct)
{
- int len;
+#ifdef CONFIG_NF_CONNTRACK_SECMARK
+ int len, ret;

- security_secid_to_secctx(ct->secmark, NULL, &len);
+ ret = security_secid_to_secctx(ct->secmark, NULL, &len);
+ if (ret)
+ return 0;

- return sizeof(char) * len;
-}
+ return nla_total_size(0) /* CTA_SECCTX */
+ + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
+#else
+ return 0;
#endif
+}

static inline size_t
ctnetlink_nlmsg_size(const struct nf_conn *ct)
@@ -479,10 +485,7 @@ ctnetlink_nlmsg_size(const struct nf_con
+ nla_total_size(0) /* CTA_PROTOINFO */
+ nla_total_size(0) /* CTA_HELP */
+ nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
-#ifdef CONFIG_NF_CONNTRACK_SECMARK
- + nla_total_size(0) /* CTA_SECCTX */
- + nla_total_size(ctnetlink_nlmsg_secctx_size(ct)) /* CTA_SECCTX_NAME */
-#endif
+ + ctnetlink_secctx_size(ct)
#ifdef CONFIG_NF_NAT_NEEDED
+ 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
+ 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -118,7 +118,7 @@ static int ct_show_secctx(struct seq_fil

ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
if (ret)
- return ret;
+ return 0;

ret = seq_printf(s, "secctx=%s ", secctx);




\
 
 \ /
  Last update: 2011-03-22 00:55    [W:0.349 / U:0.216 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site