UPSTREAM: netfilter: x_tables: fix pointer leaks to userspace
Several netfilter matches and targets put kernel pointers into
info objects, but don't set usersize in descriptors.
This leads to kernel pointer leaks if a match/target is set
and then read back to userspace.
Properly set usersize for these matches/targets.
Found with manual code inspection.
Bug: 187527909
Fixes: ec2318904965 ("xtables: extend matches and targets with .usersize")
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: If4d4beb7429c38d9b359cb2a929c71aef84f6cd0
(cherry picked from commit 1e98ffea5a8935ec040ab72299e349cb44b8defd)
Signed-off-by: Hridya Valsaraju <hridya@google.com>
diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c
index 44c42a7..ff49016 100644
--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -497,6 +497,7 @@ static struct xt_target idletimer_tg __read_mostly = {
.family = NFPROTO_UNSPEC,
.target = idletimer_tg_target,
.targetsize = sizeof(struct idletimer_tg_info),
+ .usersize = offsetof(struct idletimer_tg_info, timer),
.checkentry = idletimer_tg_checkentry,
.destroy = idletimer_tg_destroy,
.me = THIS_MODULE,
diff --git a/net/netfilter/xt_LED.c b/net/netfilter/xt_LED.c
index 0858fe1..2d1c5c1 100644
--- a/net/netfilter/xt_LED.c
+++ b/net/netfilter/xt_LED.c
@@ -198,6 +198,7 @@ static struct xt_target led_tg_reg __read_mostly = {
.family = NFPROTO_UNSPEC,
.target = led_tg,
.targetsize = sizeof(struct xt_led_info),
+ .usersize = offsetof(struct xt_led_info, internal_data),
.checkentry = led_tg_check,
.destroy = led_tg_destroy,
.me = THIS_MODULE,
diff --git a/net/netfilter/xt_limit.c b/net/netfilter/xt_limit.c
index dab962d..e84de76 100644
--- a/net/netfilter/xt_limit.c
+++ b/net/netfilter/xt_limit.c
@@ -192,9 +192,8 @@ static struct xt_match limit_mt_reg __read_mostly = {
.compatsize = sizeof(struct compat_xt_rateinfo),
.compat_from_user = limit_mt_compat_from_user,
.compat_to_user = limit_mt_compat_to_user,
-#else
- .usersize = offsetof(struct xt_rateinfo, prev),
#endif
+ .usersize = offsetof(struct xt_rateinfo, prev),
.me = THIS_MODULE,
};
diff --git a/net/netfilter/xt_nfacct.c b/net/netfilter/xt_nfacct.c
index cf32759..51541c5 100644
--- a/net/netfilter/xt_nfacct.c
+++ b/net/netfilter/xt_nfacct.c
@@ -62,6 +62,7 @@ static struct xt_match nfacct_mt_reg __read_mostly = {
.match = nfacct_mt,
.destroy = nfacct_mt_destroy,
.matchsize = sizeof(struct xt_nfacct_match_info),
+ .usersize = offsetof(struct xt_nfacct_match_info, nfacct),
.me = THIS_MODULE,
};
diff --git a/net/netfilter/xt_statistic.c b/net/netfilter/xt_statistic.c
index 11de55e..8710fdb 100644
--- a/net/netfilter/xt_statistic.c
+++ b/net/netfilter/xt_statistic.c
@@ -84,6 +84,7 @@ static struct xt_match xt_statistic_mt_reg __read_mostly = {
.checkentry = statistic_mt_check,
.destroy = statistic_mt_destroy,
.matchsize = sizeof(struct xt_statistic_info),
+ .usersize = offsetof(struct xt_statistic_info, master),
.me = THIS_MODULE,
};
