From 4f8b69a3a2521fb9b67008532975ca0e3371c3fc Mon Sep 17 00:00:00 2001 From: Justin M. Forbes Date: Mar 28 2017 15:35:38 +0000 Subject: CVE-2017-7277 SCM_TIMESTAMPING_OPT_STATS feature causes out-of-bounds read (rhbz 1436629 1436661) --- diff --git a/kernel.spec b/kernel.spec index 298feec..b7f1e51 100644 --- a/kernel.spec +++ b/kernel.spec @@ -611,6 +611,9 @@ Patch856: genetlink-fix-counting-regression-on-ctrl_dumpfamily.patch #CVE-2017-7261 rhbz 1435719 1435740 Patch857: vmwgfx-check-that-number-of-mip-levels-is-above-zero.patch +#CVE-2017-7277 rhbz 1436629 1436661 +Patch858: tcp-mark-skbs-with-SCM_TIMESTAMPING_OPT_STATS.patch + # END OF PATCH DEFINITIONS %endif @@ -2180,6 +2183,9 @@ fi # # %changelog +* Tue Mar 28 2017 Justin M. Forbes +- CVE-2017-7277 SCM_TIMESTAMPING_OPT_STATS feature causes out-of-bounds read (rhbz 1436629 1436661) + * Mon Mar 27 2017 Justin M. Forbes - CVE-2017-7261 vmwgfx: check that number of mip levels is above zero (rhbz 1435719 1435740) diff --git a/tcp-mark-skbs-with-SCM_TIMESTAMPING_OPT_STATS.patch b/tcp-mark-skbs-with-SCM_TIMESTAMPING_OPT_STATS.patch new file mode 100644 index 0000000..9eabfc0 --- /dev/null +++ b/tcp-mark-skbs-with-SCM_TIMESTAMPING_OPT_STATS.patch @@ -0,0 +1,119 @@ +From 4ef1b2869447411ad3ef91ad7d4891a83c1a509a Mon Sep 17 00:00:00 2001 +From: Soheil Hassas Yeganeh +Date: Sat, 18 Mar 2017 17:03:00 -0400 +Subject: [PATCH] tcp: mark skbs with SCM_TIMESTAMPING_OPT_STATS + +SOF_TIMESTAMPING_OPT_STATS can be enabled and disabled +while packets are collected on the error queue. +So, checking SOF_TIMESTAMPING_OPT_STATS in sk->sk_tsflags +is not enough to safely assume that the skb contains +OPT_STATS data. + +Add a bit in sock_exterr_skb to indicate whether the +skb contains opt_stats data. + +Fixes: 1c885808e456 ("tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING") +Reported-by: JongHwan Kim +Signed-off-by: Soheil Hassas Yeganeh +Signed-off-by: Eric Dumazet +Signed-off-by: Willem de Bruijn +Signed-off-by: David S. Miller +--- + include/linux/errqueue.h | 2 ++ + net/core/skbuff.c | 17 +++++++++++------ + net/socket.c | 2 +- + 3 files changed, 14 insertions(+), 7 deletions(-) + +diff --git a/include/linux/errqueue.h b/include/linux/errqueue.h +index 9ca23fc..6fdfc88 100644 +--- a/include/linux/errqueue.h ++++ b/include/linux/errqueue.h +@@ -20,6 +20,8 @@ struct sock_exterr_skb { + struct sock_extended_err ee; + u16 addr_offset; + __be16 port; ++ u8 opt_stats:1, ++ unused:7; + }; + + #endif +diff --git a/net/core/skbuff.c b/net/core/skbuff.c +index b1fbd19..9f78109 100644 +--- a/net/core/skbuff.c ++++ b/net/core/skbuff.c +@@ -3793,16 +3793,20 @@ EXPORT_SYMBOL(skb_clone_sk); + + static void __skb_complete_tx_timestamp(struct sk_buff *skb, + struct sock *sk, +- int tstype) ++ int tstype, ++ bool opt_stats) + { + struct sock_exterr_skb *serr; + int err; + ++ BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb)); ++ + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = tstype; ++ serr->opt_stats = opt_stats; + if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) { + serr->ee.ee_data = skb_shinfo(skb)->tskey; + if (sk->sk_protocol == IPPROTO_TCP && +@@ -3843,7 +3847,7 @@ void skb_complete_tx_timestamp(struct sk_buff *skb, + */ + if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) { + *skb_hwtstamps(skb) = *hwtstamps; +- __skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND); ++ __skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND, false); + sock_put(sk); + } + } +@@ -3854,7 +3858,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, + struct sock *sk, int tstype) + { + struct sk_buff *skb; +- bool tsonly; ++ bool tsonly, opt_stats = false; + + if (!sk) + return; +@@ -3867,9 +3871,10 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, + #ifdef CONFIG_INET + if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) && + sk->sk_protocol == IPPROTO_TCP && +- sk->sk_type == SOCK_STREAM) ++ sk->sk_type == SOCK_STREAM) { + skb = tcp_get_timestamping_opt_stats(sk); +- else ++ opt_stats = true; ++ } else + #endif + skb = alloc_skb(0, GFP_ATOMIC); + } else { +@@ -3888,7 +3893,7 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, + else + skb->tstamp = ktime_get_real(); + +- __skb_complete_tx_timestamp(skb, sk, tstype); ++ __skb_complete_tx_timestamp(skb, sk, tstype, opt_stats); + } + EXPORT_SYMBOL_GPL(__skb_tstamp_tx); + + +diff --git a/net/socket.c b/net/socket.c +index 02bd924..84e3f85 100644 +--- a/net/socket.c ++++ b/net/socket.c +@@ -697,7 +697,7 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, + put_cmsg(msg, SOL_SOCKET, + SCM_TIMESTAMPING, sizeof(tss), &tss); + +- if (skb->len && (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS)) ++ if (skb->len && SKB_EXT_ERR(skb)->opt_stats) + put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPING_OPT_STATS, + skb->len, skb->data); + }