diff options
| author | David S. Miller <davem@davemloft.net> | 2021-06-10 14:26:18 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-06-10 14:26:18 -0700 |
| commit | 0280f429dc21d7b8196c401990eab6abe630006f (patch) | |
| tree | 747752d7c9d0866bd600032a7e6fcadf4b403215 | |
| parent | d1b5bee4c8be01585033be9b3a8878789285285f (diff) | |
| parent | ba91c49dedbde758ba0b72f57ac90b06ddf8e548 (diff) | |
Merge branch 'tcp-options-oob-fixes'
Maxim Mikityanskiy says:
====================
Fix out of bounds when parsing TCP options
This series fixes out-of-bounds access in various places in the kernel
where parsing of TCP options takes place. Fortunately, many more
occurrences don't have this bug.
v2 changes:
synproxy: Added an early return when length < 0 to avoid calling
skb_header_pointer with negative length.
sch_cake: Added doff validation to avoid parsing garbage.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/mptcp/options.c | 2 | ||||
| -rw-r--r-- | net/netfilter/nf_synproxy_core.c | 5 | ||||
| -rw-r--r-- | net/sched/sch_cake.c | 6 |
3 files changed, 12 insertions, 1 deletions
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 6b825fb3fa83..9b263f27ce9b 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -356,6 +356,8 @@ void mptcp_get_options(const struct sk_buff *skb, length--; continue; default: + if (length < 2) + return; opsize = *ptr++; if (opsize < 2) /* "silly options" */ return; diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c index b100c04a0e43..3d6d49420db8 100644 --- a/net/netfilter/nf_synproxy_core.c +++ b/net/netfilter/nf_synproxy_core.c @@ -31,6 +31,9 @@ synproxy_parse_options(const struct sk_buff *skb, unsigned int doff, int length = (th->doff * 4) - sizeof(*th); u8 buf[40], *ptr; + if (unlikely(length < 0)) + return false; + ptr = skb_header_pointer(skb, doff + sizeof(*th), length, buf); if (ptr == NULL) return false; @@ -47,6 +50,8 @@ synproxy_parse_options(const struct sk_buff *skb, unsigned int doff, length--; continue; default: + if (length < 2) + return true; opsize = *ptr++; if (opsize < 2) return true; diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index 7d37638ee1c7..5c15968b5155 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -943,7 +943,7 @@ static struct tcphdr *cake_get_tcphdr(const struct sk_buff *skb, } tcph = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); - if (!tcph) + if (!tcph || tcph->doff < 5) return NULL; return skb_header_pointer(skb, offset, @@ -967,6 +967,8 @@ static const void *cake_get_tcpopt(const struct tcphdr *tcph, length--; continue; } + if (length < 2) + break; opsize = *ptr++; if (opsize < 2 || opsize > length) break; @@ -1104,6 +1106,8 @@ static bool cake_tcph_may_drop(const struct tcphdr *tcph, length--; continue; } + if (length < 2) + break; opsize = *ptr++; if (opsize < 2 || opsize > length) break; |