4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit 18f039428c7df183b09c69ebf10ffd4e521035d2 ] Inspired by syzbot reports using a stack of multiple ipvlan devices. Reduce stack size needed in ipvlan_process_v6_outbound() by moving the flowi6 struct used for the route lookup in an non inlined helper. ipvlan_route_v6_outbound() needs 120 bytes on the stack, immediately reclaimed. Also make sure ipvlan_process_v4_outbound() is not inlined. We might also have to lower MAX_NEST_DEV, because only syzbot uses setups with more than four stacked devices. BUG: TASK stack guard page was hit at ffffc9000e803ff8 (stack is ffffc9000e804000..ffffc9000e808000) stack guard page: 0000 [#1] SMP KASAN CPU: 0 PID: 13442 Comm: syz-executor.4 Not tainted 6.1.52-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 RIP: 0010:kasan_check_range+0x4/0x2a0 mm/kasan/generic.c:188 Code: 48 01 c6 48 89 c7 e8 db 4e c1 03 31 c0 5d c3 cc 0f 0b eb 02 0f 0b b8 ea ff ff ff 5d c3 cc 00 00 cc cc 00 00 cc cc 55 48 89 e5 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 a4 01 00 00 48 89 RSP: 0018:ffffc9000e804000 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817e5bf2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff887c6568 RBP: ffffc9000e804000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001d0080c R13: dffffc0000000000 R14: ffffffff87e6b100 R15: 0000000000000000 FS: 00007fd0c55826c0(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc9000e803ff8 CR3: 0000000170ef7000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <#DF> </#DF> <TASK> [<ffffffff81f281d1>] __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31 [<ffffffff817e5bf2>] instrument_atomic_read include/linux/instrumented.h:72 [inline] [<ffffffff817e5bf2>] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] [<ffffffff817e5bf2>] cpumask_test_cpu include/linux/cpumask.h:506 [inline] [<ffffffff817e5bf2>] cpu_online include/linux/cpumask.h:1092 [inline] [<ffffffff817e5bf2>] trace_lock_acquire include/trace/events/lock.h:24 [inline] [<ffffffff817e5bf2>] lock_acquire+0xe2/0x590 kernel/locking/lockdep.c:5632 [<ffffffff8563221e>] rcu_lock_acquire+0x2e/0x40 include/linux/rcupdate.h:306 [<ffffffff8561464d>] rcu_read_lock include/linux/rcupdate.h:747 [inline] [<ffffffff8561464d>] ip6_pol_route+0x15d/0x1440 net/ipv6/route.c:2221 [<ffffffff85618120>] ip6_pol_route_output+0x50/0x80 net/ipv6/route.c:2606 [<ffffffff856f65b5>] pol_lookup_func include/net/ip6_fib.h:584 [inline] [<ffffffff856f65b5>] fib6_rule_lookup+0x265/0x620 net/ipv6/fib6_rules.c:116 [<ffffffff85618009>] ip6_route_output_flags_noref+0x2d9/0x3a0 net/ipv6/route.c:2638 [<ffffffff8561821a>] ip6_route_output_flags+0xca/0x340 net/ipv6/route.c:2651 [<ffffffff838bd5a3>] ip6_route_output include/net/ip6_route.h:100 [inline] [<ffffffff838bd5a3>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:473 [inline] [<ffffffff838bd5a3>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff838bd5a3>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff838bd5a3>] ipvlan_queue_xmit+0xc33/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline] [<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline] [<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline] [<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline] [<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139 [<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline] [<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161 [<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline] [<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline] [<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline] [<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline] [<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline] [<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139 [<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline] [<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161 [<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline] [<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline] [<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline] [<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline] [<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline] [<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139 [<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline] [<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161 [<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline] [<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline] [<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline] [<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline] [<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline] [<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139 [<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline] [<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161 [<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline] [<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline] [<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324 [<ffffffff84d4a65e>] dev_queue_xmit include/linux/netdevice.h:3067 [inline] [<ffffffff84d4a65e>] neigh_resolve_output+0x64e/0x750 net/core/neighbour.c:1560 [<ffffffff855ce503>] neigh_output include/net/neighbour.h:545 [inline] [<ffffffff855ce503>] ip6_finish_output2+0x1643/0x1ae0 net/ipv6/ip6_output.c:139 [<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff855b9ce4>] dst_output include/net/dst.h:444 [inline] [<ffffffff855b9ce4>] NF_HOOK include/linux/netfilter.h:309 [inline] [<ffffffff855b9ce4>] ip6_xmit+0x11a4/0x1b20 net/ipv6/ip6_output.c:352 [<ffffffff8597984e>] sctp_v6_xmit+0x9ae/0x1230 net/sctp/ipv6.c:250 [<ffffffff8594623e>] sctp_packet_transmit+0x25de/0x2bc0 net/sctp/output.c:653 [<ffffffff858f5142>] sctp_packet_singleton+0x202/0x310 net/sctp/outqueue.c:783 [<ffffffff858ea411>] sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline] [<ffffffff858ea411>] sctp_outq_flush+0x661/0x3d40 net/sctp/outqueue.c:1212 [<ffffffff858f02f9>] sctp_outq_uncork+0x79/0xb0 net/sctp/outqueue.c:764 [<ffffffff8589f060>] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] [<ffffffff8589f060>] sctp_do_sm+0x55c0/0x5c30 net/sctp/sm_sideeffect.c:1170 [<ffffffff85941567>] sctp_primitive_ASSOCIATE+0x97/0xc0 net/sctp/primitive.c:73 [<ffffffff859408b2>] sctp_sendmsg_to_asoc+0xf62/0x17b0 net/sctp/socket.c:1839 [<ffffffff85910b5e>] sctp_sendmsg+0x212e/0x33b0 net/sctp/socket.c:2029 [<ffffffff8544d559>] inet_sendmsg+0x149/0x310 net/ipv4/af_inet.c:849 [<ffffffff84c6c4d2>] sock_sendmsg_nosec net/socket.c:716 [inline] [<ffffffff84c6c4d2>] sock_sendmsg net/socket.c:736 [inline] [<ffffffff84c6c4d2>] ____sys_sendmsg+0x572/0x8c0 net/socket.c:2504 [<ffffffff84c6ca91>] ___sys_sendmsg net/socket.c:2558 [inline] [<ffffffff84c6ca91>] __sys_sendmsg+0x271/0x360 net/socket.c:2587 [<ffffffff84c6cbff>] __do_sys_sendmsg net/socket.c:2596 [inline] [<ffffffff84c6cbff>] __se_sys_sendmsg net/socket.c:2594 [inline] [<ffffffff84c6cbff>] __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2594 [<ffffffff85b32553>] do_syscall_x64 arch/x86/entry/common.c:51 [inline] [<ffffffff85b32553>] do_syscall_64+0x53/0x80 arch/x86/entry/common.c:84 [<ffffffff85c00087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 2ad7bf363841 ("ipvlan: Initial check-in of the IPVLAN driver.") Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Mahesh Bandewar <maheshb@xxxxxxxxxx> Cc: Willem de Bruijn <willemb@xxxxxxxxxx> Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ipvlan/ipvlan_core.c | 41 +++++++++++++++++++------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/drivers/net/ipvlan/ipvlan_core.c b/drivers/net/ipvlan/ipvlan_core.c index ecb10fb249af4..34126abb28d8d 100644 --- a/drivers/net/ipvlan/ipvlan_core.c +++ b/drivers/net/ipvlan/ipvlan_core.c @@ -418,7 +418,7 @@ static struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port, return addr; } -static int ipvlan_process_v4_outbound(struct sk_buff *skb) +static noinline_for_stack int ipvlan_process_v4_outbound(struct sk_buff *skb) { const struct iphdr *ip4h = ip_hdr(skb); struct net_device *dev = skb->dev; @@ -460,13 +460,11 @@ static int ipvlan_process_v4_outbound(struct sk_buff *skb) } #if IS_ENABLED(CONFIG_IPV6) -static int ipvlan_process_v6_outbound(struct sk_buff *skb) + +static noinline_for_stack int +ipvlan_route_v6_outbound(struct net_device *dev, struct sk_buff *skb) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); - struct net_device *dev = skb->dev; - struct net *net = dev_net(dev); - struct dst_entry *dst; - int err, ret = NET_XMIT_DROP; struct flowi6 fl6 = { .flowi6_oif = dev->ifindex, .daddr = ip6h->daddr, @@ -476,27 +474,38 @@ static int ipvlan_process_v6_outbound(struct sk_buff *skb) .flowi6_mark = skb->mark, .flowi6_proto = ip6h->nexthdr, }; + struct dst_entry *dst; + int err; - dst = ip6_route_output(net, NULL, &fl6); - if (dst->error) { - ret = dst->error; + dst = ip6_route_output(dev_net(dev), NULL, &fl6); + err = dst->error; + if (err) { dst_release(dst); - goto err; + return err; } skb_dst_set(skb, dst); + return 0; +} + +static int ipvlan_process_v6_outbound(struct sk_buff *skb) +{ + struct net_device *dev = skb->dev; + int err, ret = NET_XMIT_DROP; + + err = ipvlan_route_v6_outbound(dev, skb); + if (unlikely(err)) { + DEV_STATS_INC(dev, tx_errors); + kfree_skb(skb); + return err; + } memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); - err = ip6_local_out(net, skb->sk, skb); + err = ip6_local_out(dev_net(dev), skb->sk, skb); if (unlikely(net_xmit_eval(err))) DEV_STATS_INC(dev, tx_errors); else ret = NET_XMIT_SUCCESS; - goto out; -err: - DEV_STATS_INC(dev, tx_errors); - kfree_skb(skb); -out: return ret; } #else -- 2.42.0