diff options
| author |   Eric Dumazet <edumazet@google.com> | 2018-01-24 17:16:09 -0800 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2018-01-25 12:31:34 +0100 |
| commit | da17c73b6eb74aad3c3c0654394635675b623b3e (patch) | |
| tree | 18783216423e8a3bbf86391b2e940424c0b2dba4 /net/netfilter/x_tables.c | |
| parent | netfilter: x_tables: fix int overflow in xt_alloc_table_info() (diff) | |
| download | linux-dev-da17c73b6eb74aad3c3c0654394635675b623b3e.tar.xz linux-dev-da17c73b6eb74aad3c3c0654394635675b623b3e.zip | |
netfilter: x_tables: avoid out-of-bounds reads in xt_request_find_{match|target}
It looks like syzbot found its way into netfilter territory.
Issue here is that @name comes from user space and might
not be null terminated.
Out-of-bound reads happen, KASAN is not happy.
v2 added similar fix for xt_request_find_target(),
as Florian advised.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to '')
| -rw-r--r-- | net/netfilter/x_tables.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index e02a21549c99..d7070d18db20 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -209,6 +209,9 @@ xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision) { struct xt_match *match; + if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN) + return ERR_PTR(-EINVAL); + match = xt_find_match(nfproto, name, revision); if (IS_ERR(match)) { request_module("%st_%s", xt_prefix[nfproto], name); @@ -251,6 +254,9 @@ struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision) { struct xt_target *target; + if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN) + return ERR_PTR(-EINVAL); + target = xt_find_target(af, name, revision); if (IS_ERR(target)) { request_module("%st_%s", xt_prefix[af], name); |