[PATCH AUTOSEL 4.4 1/8] xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink

[PATCH AUTOSEL 4.4 1/8] xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink

[Sasha Levin]

From: YueHaibing <yuehaibing@huawei.com>

[ Upstream commit b805d78d300bcf2c83d6df7da0c818b0fee41427 ]

UBSAN report this:

UBSAN: Undefined behaviour in net/xfrm/xfrm_policy.c:1289:24
index 6 is out of range for type 'unsigned int [6]'
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.162-514.55.6.9.x86_64+ #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
 0000000000000000 1466cf39b41b23c9 ffff8801f6b07a58 ffffffff81cb35f4
 0000000041b58ab3 ffffffff83230f9c ffffffff81cb34e0 ffff8801f6b07a80
 ffff8801f6b07a20 1466cf39b41b23c9 ffffffff851706e0 ffff8801f6b07ae8
Call Trace:
 <IRQ>  [<ffffffff81cb35f4>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ>  [<ffffffff81cb35f4>] dump_stack+0x114/0x1a0 lib/dump_stack.c:51
 [<ffffffff81d94225>] ubsan_epilogue+0x12/0x8f lib/ubsan.c:164
 [<ffffffff81d954db>] __ubsan_handle_out_of_bounds+0x16e/0x1b2 lib/ubsan.c:382
 [<ffffffff82a25acd>] __xfrm_policy_unlink+0x3dd/0x5b0 net/xfrm/xfrm_policy.c:1289
 [<ffffffff82a2e572>] xfrm_policy_delete+0x52/0xb0 net/xfrm/xfrm_policy.c:1309
 [<ffffffff82a3319b>] xfrm_policy_timer+0x30b/0x590 net/xfrm/xfrm_policy.c:243
 [<ffffffff813d3927>] call_timer_fn+0x237/0x990 kernel/time/timer.c:1144
 [<ffffffff813d8e7e>] __run_timers kernel/time/timer.c:1218 [inline]
 [<ffffffff813d8e7e>] run_timer_softirq+0x6ce/0xb80 kernel/time/timer.c:1401
 [<ffffffff8120d6f9>] __do_softirq+0x299/0xe10 kernel/softirq.c:273
 [<ffffffff8120e676>] invoke_softirq kernel/softirq.c:350 [inline]
 [<ffffffff8120e676>] irq_exit+0x216/0x2c0 kernel/softirq.c:391
 [<ffffffff82c5edab>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
 [<ffffffff82c5edab>] smp_apic_timer_interrupt+0x8b/0xc0 arch/x86/kernel/apic/apic.c:926
 [<ffffffff82c5c985>] apic_timer_interrupt+0xa5/0xb0 arch/x86/entry/entry_64.S:735
 <EOI>  [<ffffffff81188096>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:52
 [<ffffffff810834d7>] arch_safe_halt arch/x86/include/asm/paravirt.h:111 [inline]
 [<ffffffff810834d7>] default_idle+0x27/0x430 arch/x86/kernel/process.c:446
 [<ffffffff81085f05>] arch_cpu_idle+0x15/0x20 arch/x86/kernel/process.c:437
 [<ffffffff8132abc3>] default_idle_call+0x53/0x90 kernel/sched/idle.c:92
 [<ffffffff8132b32d>] cpuidle_idle_call kernel/sched/idle.c:156 [inline]
 [<ffffffff8132b32d>] cpu_idle_loop kernel/sched/idle.c:251 [inline]
 [<ffffffff8132b32d>] cpu_startup_entry+0x60d/0x9a0 kernel/sched/idle.c:299
 [<ffffffff8113e119>] start_secondary+0x3c9/0x560 arch/x86/kernel/smpboot.c:245

The issue is triggered as this:

xfrm_add_policy
    -->verify_newpolicy_info  //check the index provided by user with XFRM_POLICY_MAX
			      //In my case, the index is 0x6E6BB6, so it pass the check.
    -->xfrm_policy_construct  //copy the user's policy and set xfrm_policy_timer
    -->xfrm_policy_insert
	--> __xfrm_policy_link //use the orgin dir, in my case is 2
	--> xfrm_gen_index   //generate policy index, there is 0x6E6BB6

then xfrm_policy_timer be fired

xfrm_policy_timer
   --> xfrm_policy_id2dir  //get dir from (policy index & 7), in my case is 6
   --> xfrm_policy_delete
      --> __xfrm_policy_unlink //access policy_count[dir], trigger out of range access

Add xfrm_policy_id2dir check in verify_newpolicy_info, make sure the computed dir is
valid, to fix the issue.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: e682adf021be ("xfrm: Try to honor policy index if it's supplied by user")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/xfrm/xfrm_user.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 177a6c75f136b..b04c030439762 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1340,7 +1340,7 @@ static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
 	ret = verify_policy_dir(p->dir);
 	if (ret)
 		return ret;
-	if (p->index && ((p->index & XFRM_POLICY_MAX) != p->dir))
+	if (p->index && (xfrm_policy_id2dir(p->index) != p->dir))
 		return -EINVAL;
 
 	return 0;
-- 
2.20.1

[PATCH AUTOSEL 4.4 2/8] xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module

[Sasha Levin]

From: Su Yanjun <suyj.fnst@cn.fujitsu.com>

[ Upstream commit 6ee02a54ef990a71bf542b6f0a4e3321de9d9c66 ]

When unloading xfrm6_tunnel module, xfrm6_tunnel_fini directly
frees the xfrm6_tunnel_spi_kmem. Maybe someone has gotten the
xfrm6_tunnel_spi, so need to wait it.

Fixes: 91cc3bb0b04ff("xfrm6_tunnel: RCU conversion")
Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv6/xfrm6_tunnel.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index 56b72cada346f..f9d493c59d6c1 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -391,6 +391,10 @@ static void __exit xfrm6_tunnel_fini(void)
 	xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
 	xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
 	unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
+	/* Someone maybe has gotten the xfrm6_tunnel_spi.
+	 * So need to wait it.
+	 */
+	rcu_barrier();
 	kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
 }
 
-- 
2.20.1

[PATCH AUTOSEL 4.4 3/8] vti4: ipip tunnel deregistration fixes.

[Sasha Levin]

From: Jeremy Sowden <jeremy@azazel.net>

[ Upstream commit 5483844c3fc18474de29f5d6733003526e0a9f78 ]

If tunnel registration failed during module initialization, the module
would fail to deregister the IPPROTO_COMP protocol and would attempt to
deregister the tunnel.

The tunnel was not deregistered during module-exit.

Fixes: dd9ee3444014e ("vti4: Fix a ipip packet processing bug in 'IPCOMP' virtual tunnel")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv4/ip_vti.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index fcf327ebd1345..bbcbbc1cc2cc6 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -648,9 +648,9 @@ static int __init vti_init(void)
 	return err;
 
 rtnl_link_failed:
-	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
-xfrm_tunnel_failed:
 	xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
+xfrm_tunnel_failed:
+	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
 xfrm_proto_comp_failed:
 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
 xfrm_proto_ah_failed:
@@ -666,6 +666,7 @@ static int __init vti_init(void)
 static void __exit vti_fini(void)
 {
 	rtnl_link_unregister(&vti_link_ops);
+	xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
 	xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
 	xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
 	xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
-- 
2.20.1

[PATCH AUTOSEL 4.4 4/8] xfrm4: Fix uninitialized memory read in _decode_session4

[Sasha Levin]

From: Steffen Klassert <steffen.klassert@secunet.com>

[ Upstream commit 8742dc86d0c7a9628117a989c11f04a9b6b898f3 ]

We currently don't reload pointers pointing into skb header
after doing pskb_may_pull() in _decode_session4(). So in case
pskb_may_pull() changed the pointers, we read from random
memory. Fix this by putting all the needed infos on the
stack, so that we don't need to access the header pointers
after doing pskb_may_pull().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv4/xfrm4_policy.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index fddae0164b918..d9758ecdcba6a 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -108,7 +108,8 @@ static void
 _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 {
 	const struct iphdr *iph = ip_hdr(skb);
-	u8 *xprth = skb_network_header(skb) + iph->ihl * 4;
+	int ihl = iph->ihl;
+	u8 *xprth = skb_network_header(skb) + ihl * 4;
 	struct flowi4 *fl4 = &fl->u.ip4;
 	int oif = 0;
 
@@ -119,6 +120,11 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 	fl4->flowi4_mark = skb->mark;
 	fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
 
+	fl4->flowi4_proto = iph->protocol;
+	fl4->daddr = reverse ? iph->saddr : iph->daddr;
+	fl4->saddr = reverse ? iph->daddr : iph->saddr;
+	fl4->flowi4_tos = iph->tos;
+
 	if (!ip_is_fragment(iph)) {
 		switch (iph->protocol) {
 		case IPPROTO_UDP:
@@ -130,7 +136,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
 				__be16 *ports;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				ports = (__be16 *)xprth;
 
 				fl4->fl4_sport = ports[!!reverse];
@@ -143,7 +149,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			    pskb_may_pull(skb, xprth + 2 - skb->data)) {
 				u8 *icmp;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				icmp = xprth;
 
 				fl4->fl4_icmp_type = icmp[0];
@@ -156,7 +162,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
 				__be32 *ehdr;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				ehdr = (__be32 *)xprth;
 
 				fl4->fl4_ipsec_spi = ehdr[0];
@@ -168,7 +174,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			    pskb_may_pull(skb, xprth + 8 - skb->data)) {
 				__be32 *ah_hdr;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				ah_hdr = (__be32 *)xprth;
 
 				fl4->fl4_ipsec_spi = ah_hdr[1];
@@ -180,7 +186,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			    pskb_may_pull(skb, xprth + 4 - skb->data)) {
 				__be16 *ipcomp_hdr;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				ipcomp_hdr = (__be16 *)xprth;
 
 				fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
@@ -193,7 +199,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 				__be16 *greflags;
 				__be32 *gre_hdr;
 
-				xprth = skb_network_header(skb) + iph->ihl * 4;
+				xprth = skb_network_header(skb) + ihl * 4;
 				greflags = (__be16 *)xprth;
 				gre_hdr = (__be32 *)xprth;
 
@@ -210,10 +216,6 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 			break;
 		}
 	}
-	fl4->flowi4_proto = iph->protocol;
-	fl4->daddr = reverse ? iph->saddr : iph->daddr;
-	fl4->saddr = reverse ? iph->daddr : iph->saddr;
-	fl4->flowi4_tos = iph->tos;
 }
 
 static inline int xfrm4_garbage_collect(struct dst_ops *ops)
-- 
2.20.1