Patch "tcp: fix 0 divide in __tcp_select_window()" has been added to the 4.4-stable tree
Subsystems (3)
This is a note to let you know that I've just added the patch titled
tcp: fix 0 divide in __tcp_select_window()
to the 4.4-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:
tcp-fix-0-divide-in-__tcp_select_window.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From foo@baz Tue Feb 14 16:29:59 PST 2017
From: Eric Dumazet <[email protected]>
Date: Wed, 1 Feb 2017 08:33:53 -0800
Subject: tcp: fix 0 divide in __tcp_select_window()
From: Eric Dumazet <[email protected]>
[ Upstream commit 06425c308b92eaf60767bc71d359f4cbc7a561f8 ]
syszkaller fuzzer was able to trigger a divide by zero, when TCP window scaling is not enabled.
SO_RCVBUF can be used not only to increase sk_rcvbuf, also to decrease it below current receive buffers utilization.
If mss is negative or 0, just return a zero TCP window.
--- net/ipv4/tcp_output.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
net/ipv4/tcp_output.c +4 -2
@@ -2383,9 +2383,11 @@ u32 __tcp_select_window(struct sock *sk)int full_space =min_t (int, tp->window_clamp, allowed_space);int window; -if (mss > full_space) +if (unlikely (mss > full_space)) { mss = full_space; - +if (mss <=0 ) +return 0 ; + }if (free_space < (full_space >>1 )) { icsk->icsk_ack.quick =0 ;
Patches currently in stable-queue which might be from [email protected] are
queue-4.4/ipv6-pointer-math-error-in-ip6_tnl_parse_tlv_enc_lim.patch queue-4.4/netlabel-out-of-bound-access-in-cipso_v4_validate.patch queue-4.4/packet-round-up-linear-to-header-len.patch queue-4.4/tun-read-vnet_hdr_sz-once.patch queue-4.4/ipv6-fix-ip6_tnl_parse_tlv_enc_lim.patch queue-4.4/l2tp-do-not-use-udp_ioctl.patch queue-4.4/tcp-fix-0-divide-in-__tcp_select_window.patch queue-4.4/can-fix-kernel-panic-at-security_sock_rcv_skb.patch queue-4.4/net-introduce-device-min_header_len.patch queue-4.4/macvtap-read-vnet_hdr_size-once.patch queue-4.4/tcp-avoid-infinite-loop-in-tcp_splice_read.patch queue-4.4/mlx4-invoke-softirqs-after-napi_reschedule.patch queue-4.4/ipv6-tcp-add-a-missing-tcp_v6_restore_cb.patch queue-4.4/ipv4-keep-skb-dst-around-in-presence-of-ip-options.patch queue-4.4/net-use-a-work-queue-to-defer-net_disable_timestamp-work.patch queue-4.4/ip6_gre-fix-ip6gre_err-invalid-reads.patch