From: Xin Long <lucien.xin@gmail.com> stable inclusion from stable-v4.19.324 commit 67b9a278b80f71ec62091ded97c6bcbea33b5ec3 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB5ARH CVE: CVE-2024-50299 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... ------------------------------------------------- [ Upstream commit 0ead60804b64f5bd6999eec88e503c6a1a242d41 ] A size validation fix similar to that in Commit 50619dbf8db7 ("sctp: add size validation when walking chunks") is also required in sctp_sf_ootb() to address a crash reported by syzbot: BUG: KMSAN: uninit-value in sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712 sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712 sctp_do_sm+0x181/0x93d0 net/sctp/sm_sideeffect.c:1166 sctp_endpoint_bh_rcv+0xc38/0xf90 net/sctp/endpointola.c:407 sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88 sctp_rcv+0x3831/0x3b20 net/sctp/input.c:243 sctp4_rcv+0x42/0x50 net/sctp/protocol.c:1159 ip_protocol_deliver_rcu+0xb51/0x13d0 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233 Reported-by: syzbot+f0cbb34d39392f2746ca@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/a29ebb6d8b9f8affd0f9abb296faafafe10c17d8.1730223981... Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Liu Jian <liujian56@huawei.com> --- net/sctp/sm_statefuns.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 373be2a1be7d..bde3a8174aef 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -3652,7 +3652,7 @@ enum sctp_disposition sctp_sf_ootb(struct net *net, } ch = (struct sctp_chunkhdr *)ch_end; - } while (ch_end < skb_tail_pointer(skb)); + } while (ch_end + sizeof(*ch) < skb_tail_pointer(skb)); if (ootb_shut_ack) return sctp_sf_shut_8_4_5(net, ep, asoc, type, arg, commands); -- 2.34.1