Message ID | 20171230001523.15761-1-ebiggers3@gmail.com |
---|---|
State | Awaiting Upstream, archived |
Delegated to: | David Miller |
Headers | show |
Series | af_key: fix buffer overread in parse_exthdrs() | expand |
On Fri, Dec 29, 2017 at 06:15:23PM -0600, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > If a message sent to a PF_KEY socket ended with an incomplete extension > header (fewer than 4 bytes remaining), then parse_exthdrs() read past > the end of the message, into uninitialized memory. Fix it by returning > -EINVAL in this case. > > Reproducer: > > #include <linux/pfkeyv2.h> > #include <sys/socket.h> > #include <unistd.h> > > int main() > { > int sock = socket(PF_KEY, SOCK_RAW, PF_KEY_V2); > char buf[17] = { 0 }; > struct sadb_msg *msg = (void *)buf; > > msg->sadb_msg_version = PF_KEY_V2; > msg->sadb_msg_type = SADB_DELETE; > msg->sadb_msg_len = 2; > > write(sock, buf, 17); > } > > Cc: stable@vger.kernel.org > Signed-off-by: Eric Biggers <ebiggers@google.com> Also applied to the ipsec tree, thanks a lot!
diff --git a/net/key/af_key.c b/net/key/af_key.c index 596499cc8b2f..d40861a048fe 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -516,6 +516,9 @@ static int parse_exthdrs(struct sk_buff *skb, const struct sadb_msg *hdr, void * uint16_t ext_type; int ext_len; + if (len < sizeof(*ehdr)) + return -EINVAL; + ext_len = ehdr->sadb_ext_len; ext_len *= sizeof(uint64_t); ext_type = ehdr->sadb_ext_type;