This is a note to let you know that I've just added the patch titled
ipv4: provide stronger user input validation in nl_fib_input()
to the 4.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ipv4-provide-stronger-user-input-validation-in-nl_fib_input.patch
and it can be found in the queue-4.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon Mar 27 18:18:08 CEST 2017
From: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Tue, 21 Mar 2017 19:22:28 -0700
Subject: ipv4: provide stronger user input validation in nl_fib_input()
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/fib_frontend.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -1082,7 +1082,8 @@ static void nl_fib_input(struct sk_buff
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;
Patches currently in stable-queue which might be from edumazet@xxxxxxxxxx are
queue-4.10/ipv4-provide-stronger-user-input-validation-in-nl_fib_input.patch
queue-4.10/net-solve-a-napi-race.patch
queue-4.10/tcp-initialize-icsk_ack.lrcvtime-at-session-start-time.patch
queue-4.10/net-properly-release-sk_frag.page.patch