diff options
| author | Florian Westphal <fw@strlen.de> | 2016-04-01 14:17:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-06-24 10:18:23 -0700 |
| commit | 2985d199e713c05eec2eaffeeeac40682aa2e5cc (patch) | |
| tree | 81e47e43993e5c76f45e8f444e79f14fdb06815f /net/netfilter | |
| parent | ed30e07de077354993122c5d88e535cbe0a03754 (diff) | |
netfilter: x_tables: add compat version of xt_check_entry_offsets
commit fc1221b3a163d1386d1052184202d5dc50d302d1 upstream.
32bit rulesets have different layout and alignment requirements, so once
more integrity checks get added to xt_check_entry_offsets it will reject
well-formed 32bit rulesets.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/x_tables.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index e3e2dd4c55bf..cfdb9591cf21 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -538,6 +538,27 @@ int xt_compat_match_to_user(const struct xt_entry_match *m, return 0; } EXPORT_SYMBOL_GPL(xt_compat_match_to_user); + +int xt_compat_check_entry_offsets(const void *base, + unsigned int target_offset, + unsigned int next_offset) +{ + const struct compat_xt_entry_target *t; + const char *e = base; + + if (target_offset + sizeof(*t) > next_offset) + return -EINVAL; + + t = (void *)(e + target_offset); + if (t->u.target_size < sizeof(*t)) + return -EINVAL; + + if (target_offset + t->u.target_size > next_offset) + return -EINVAL; + + return 0; +} +EXPORT_SYMBOL(xt_compat_check_entry_offsets); #endif /* CONFIG_COMPAT */ /** @@ -548,6 +569,7 @@ EXPORT_SYMBOL_GPL(xt_compat_match_to_user); * @next_offset: the arp/ip/ip6_t->next_offset * * validates that target_offset and next_offset are sane. + * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version. * * The arp/ip/ip6t_entry structure @base must have passed following tests: * - it must point to a valid memory location |