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author | Eric Dumazet <edumazet@google.com> | 2017-03-21 19:22:28 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-30 09:44:02 +0200 |
commit | 1880e1308e9da2337b74b4241361ac54433ffd95 (patch) | |
tree | a738b036a3779bf41da4504ce6ec2cd5ad38572b /net/ipv4 | |
parent | 212508f709ab66f972481a681a29ca971d78692b (diff) | |
download | linux-stable-1880e1308e9da2337b74b4241361ac54433ffd95.tar.gz linux-stable-1880e1308e9da2337b74b4241361ac54433ffd95.tar.bz2 linux-stable-1880e1308e9da2337b74b4241361ac54433ffd95.zip |
ipv4: provide stronger user input validation in nl_fib_input()
[ Upstream commit c64c0b3cac4c5b8cb093727d2c19743ea3965c0b ]
Alexander reported a KMSAN splat caused by reads of uninitialized
field (tb_id_in) from user provided struct fib_result_nl
It turns out nl_fib_input() sanity tests on user input is a bit
wrong :
User can pretend nlh->nlmsg_len is big enough, but provide
at sendmsg() time a too small buffer.
Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/fib_frontend.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index b39a791f6756..091de0b93d5d 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1082,7 +1082,8 @@ static void nl_fib_input(struct sk_buff *skb) net = sock_net(skb->sk); nlh = nlmsg_hdr(skb); - if (skb->len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len || + if (skb->len < nlmsg_total_size(sizeof(*frn)) || + skb->len < nlh->nlmsg_len || nlmsg_len(nlh) < sizeof(*frn)) return; |