kernel/linux.git/net/ipv6, branch linux-6.0.y

ipv6/sit: use DEV_STATS_INC() to avoid data-races

2022-12-31T12:26:45+00:00

[ Upstream commit cb34b7cf17ecf33499c9298943f85af247abc1e9 ] syzbot/KCSAN reported that multiple cpus are updating dev->stats.tx_error concurrently. This is because sit tunnels are NETIF_F_LLTX, meaning their ndo_start_xmit() is not protected by a spinlock. While original KCSAN report was about tx path, rx path has the same issue. Reported-by: syzbot Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: setsockopt: fix IPV6_UNICAST_IF option for connected sockets

2022-12-31T12:26:13+00:00

[ Upstream commit 526682b458b1b56d2e0db027df535cb5cdcfde59 ] Change the behaviour of ip6_datagram_connect to consider the interface set by the IPV6_UNICAST_IF socket option, similarly to udpv6_sendmsg. This change is the IPv6 counterpart of the fix for IP_UNICAST_IF. The tests introduced by that patch showed that the incorrect behavior is present in IPv6 as well. This patch fixes the broken test. Reported-by: kernel test robot Link: https://lore.kernel.org/r/202210062117.c7eef1a3-oliver.sang@intel.com Fixes: 0e4d354762ce ("net-next: Fix IP_UNICAST_IF option behavior for connected sockets") Signed-off-by: Richard Gobert Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: Remove the obsolte u64_stats_fetch_*_irq() users (net).

2022-12-31T12:26:12+00:00

[ Upstream commit d120d1a63b2c484d6175873d8ee736a633f74b70 ] Now that the 32bit UP oddity is gone and 32bit uses always a sequence count, there is no need for the fetch_irq() variants anymore. Convert to the regular interface. Signed-off-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Acked-by: Peter Zijlstra (Intel) Signed-off-by: Jakub Kicinski Stable-dep-of: 1dbd8d9a82e3 ("ipvs: use u64_stats_t for the per-cpu counters") Signed-off-by: Sasha Levin

net: Return errno in sk->sk_prot->get_port().

2022-12-31T12:26:00+00:00

[ Upstream commit 7a7160edf1bfde25422262fb26851cef65f695d3 ] We assume the correct errno is -EADDRINUSE when sk->sk_prot->get_port() fails, so some ->get_port() functions return just 1 on failure and the callers return -EADDRINUSE instead. However, mptcp_get_port() can return -EINVAL. Let's not ignore the error. Note the only exception is inet_autobind(), all of whose callers return -EAGAIN instead. Fixes: cec37a6e41aa ("mptcp: Handle MP_CAPABLE options for outgoing connections") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

udp: Clean up some functions.

2022-12-31T12:26:00+00:00

[ Upstream commit 919dfa0b20ae56060dce0436eb710717f8987d18 ] This patch adds no functional change and cleans up some functions that the following patches touch around so that we make them tidy and easy to review/revert. The change is mainly to keep reverse christmas tree order. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Stable-dep-of: 7a7160edf1bf ("net: Return errno in sk->sk_prot->get_port().") Signed-off-by: Sasha Levin

ipv6: avoid use-after-free in ip6_fragment()

2022-12-14T10:41:05+00:00

[ Upstream commit 803e84867de59a1e5d126666d25eb4860cfd2ebe ] Blamed commit claimed rcu_read_lock() was held by ip6_fragment() callers. It seems to not be always true, at least for UDP stack. syzbot reported: BUG: KASAN: use-after-free in ip6_dst_idev include/net/ip6_fib.h:245 [inline] BUG: KASAN: use-after-free in ip6_fragment+0x2724/0x2770 net/ipv6/ip6_output.c:951 Read of size 8 at addr ffff88801d403e80 by task syz-executor.3/7618 CPU: 1 PID: 7618 Comm: syz-executor.3 Not tainted 6.1.0-rc6-syzkaller-00012-g4312098baf37 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbf/0x1f0 mm/kasan/report.c:495 ip6_dst_idev include/net/ip6_fib.h:245 [inline] ip6_fragment+0x2724/0x2770 net/ipv6/ip6_output.c:951 __ip6_finish_output net/ipv6/ip6_output.c:193 [inline] ip6_finish_output+0x9a3/0x1170 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:445 [inline] ip6_local_out+0xb3/0x1a0 net/ipv6/output_core.c:161 ip6_send_skb+0xbb/0x340 net/ipv6/ip6_output.c:1966 udp_v6_send_skb+0x82a/0x18a0 net/ipv6/udp.c:1286 udp_v6_push_pending_frames+0x140/0x200 net/ipv6/udp.c:1313 udpv6_sendmsg+0x18da/0x2c80 net/ipv6/udp.c:1606 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:665 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 sock_write_iter+0x295/0x3d0 net/socket.c:1108 call_write_iter include/linux/fs.h:2191 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9ed/0xdd0 fs/read_write.c:584 ksys_write+0x1ec/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fde3588c0d9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fde365b6168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fde359ac050 RCX: 00007fde3588c0d9 RDX: 000000000000ffdc RSI: 00000000200000c0 RDI: 000000000000000a RBP: 00007fde358e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fde35acfb1f R14: 00007fde365b6300 R15: 0000000000022000 Allocated by task 7618: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x82/0x90 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x2b4/0x3d0 mm/slub.c:3422 dst_alloc+0x14a/0x1f0 net/core/dst.c:92 ip6_dst_alloc+0x32/0xa0 net/ipv6/route.c:344 ip6_rt_pcpu_alloc net/ipv6/route.c:1369 [inline] rt6_make_pcpu_route net/ipv6/route.c:1417 [inline] ip6_pol_route+0x901/0x1190 net/ipv6/route.c:2254 pol_lookup_func include/net/ip6_fib.h:582 [inline] fib6_rule_lookup+0x52e/0x6f0 net/ipv6/fib6_rules.c:121 ip6_route_output_flags_noref+0x2e6/0x380 net/ipv6/route.c:2625 ip6_route_output_flags+0x76/0x320 net/ipv6/route.c:2638 ip6_route_output include/net/ip6_route.h:98 [inline] ip6_dst_lookup_tail+0x5ab/0x1620 net/ipv6/ip6_output.c:1092 ip6_dst_lookup_flow+0x90/0x1d0 net/ipv6/ip6_output.c:1222 ip6_sk_dst_lookup_flow+0x553/0x980 net/ipv6/ip6_output.c:1260 udpv6_sendmsg+0x151d/0x2c80 net/ipv6/udp.c:1554 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:665 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 __sys_sendto+0x23a/0x340 net/socket.c:2117 __do_sys_sendto net/socket.c:2129 [inline] __se_sys_sendto net/socket.c:2125 [inline] __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7599: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] kmem_cache_free+0xee/0x5c0 mm/slub.c:3683 dst_destroy+0x2ea/0x400 net/core/dst.c:127 rcu_do_batch kernel/rcu/tree.c:2250 [inline] rcu_core+0x81f/0x1980 kernel/rcu/tree.c:2510 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 call_rcu+0x9d/0x820 kernel/rcu/tree.c:2798 dst_release net/core/dst.c:177 [inline] dst_release+0x7d/0xe0 net/core/dst.c:167 refdst_drop include/net/dst.h:256 [inline] skb_dst_drop include/net/dst.h:268 [inline] skb_release_head_state+0x250/0x2a0 net/core/skbuff.c:838 skb_release_all net/core/skbuff.c:852 [inline] __kfree_skb net/core/skbuff.c:868 [inline] kfree_skb_reason+0x151/0x4b0 net/core/skbuff.c:891 kfree_skb_list_reason+0x4b/0x70 net/core/skbuff.c:901 kfree_skb_list include/linux/skbuff.h:1227 [inline] ip6_fragment+0x2026/0x2770 net/ipv6/ip6_output.c:949 __ip6_finish_output net/ipv6/ip6_output.c:193 [inline] ip6_finish_output+0x9a3/0x1170 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:445 [inline] ip6_local_out+0xb3/0x1a0 net/ipv6/output_core.c:161 ip6_send_skb+0xbb/0x340 net/ipv6/ip6_output.c:1966 udp_v6_send_skb+0x82a/0x18a0 net/ipv6/udp.c:1286 udp_v6_push_pending_frames+0x140/0x200 net/ipv6/udp.c:1313 udpv6_sendmsg+0x18da/0x2c80 net/ipv6/udp.c:1606 inet6_sendmsg+0x9d/0xe0 net/ipv6/af_inet6.c:665 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 sock_write_iter+0x295/0x3d0 net/socket.c:1108 call_write_iter include/linux/fs.h:2191 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9ed/0xdd0 fs/read_write.c:584 ksys_write+0x1ec/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 call_rcu+0x9d/0x820 kernel/rcu/tree.c:2798 dst_release net/core/dst.c:177 [inline] dst_release+0x7d/0xe0 net/core/dst.c:167 refdst_drop include/net/dst.h:256 [inline] skb_dst_drop include/net/dst.h:268 [inline] __dev_queue_xmit+0x1b9d/0x3ba0 net/core/dev.c:4211 dev_queue_xmit include/linux/netdevice.h:3008 [inline] neigh_resolve_output net/core/neighbour.c:1552 [inline] neigh_resolve_output+0x51b/0x840 net/core/neighbour.c:1532 neigh_output include/net/neighbour.h:546 [inline] ip6_finish_output2+0x56c/0x1530 net/ipv6/ip6_output.c:134 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline] ip6_finish_output+0x694/0x1170 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:445 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] NF_HOOK include/linux/netfilter.h:296 [inline] mld_sendpack+0xa09/0xe70 net/ipv6/mcast.c:1820 mld_send_cr net/ipv6/mcast.c:2121 [inline] mld_ifc_work+0x720/0xdc0 net/ipv6/mcast.c:2653 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff88801d403dc0 which belongs to the cache ip6_dst_cache of size 240 The buggy address is located 192 bytes inside of 240-byte region [ffff88801d403dc0, ffff88801d403eb0) The buggy address belongs to the physical page: page:ffffea00007500c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d403 memcg:ffff888022f49c81 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0001ef6580 dead000000000002 ffff88814addf640 raw: 0000000000000000 00000000800c000c 00000001ffffffff ffff888022f49c81 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 3719, tgid 3719 (kworker/0:6), ts 136223432244, free_ts 136222971441 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4288 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5555 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2285 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x31a/0x3d0 mm/slub.c:3422 dst_alloc+0x14a/0x1f0 net/core/dst.c:92 ip6_dst_alloc+0x32/0xa0 net/ipv6/route.c:344 icmp6_dst_alloc+0x71/0x680 net/ipv6/route.c:3261 mld_sendpack+0x5de/0xe70 net/ipv6/mcast.c:1809 mld_send_cr net/ipv6/mcast.c:2121 [inline] mld_ifc_work+0x720/0xdc0 net/ipv6/mcast.c:2653 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1509 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x1d/0x4d0 mm/page_alloc.c:3483 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2586 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x184/0x210 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x66/0x90 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x304/0x410 mm/slub.c:3443 __alloc_skb+0x214/0x300 net/core/skbuff.c:497 alloc_skb include/linux/skbuff.h:1267 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline] netlink_sendmsg+0x9a6/0xe10 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 __sys_sendto+0x23a/0x340 net/socket.c:2117 __do_sys_sendto net/socket.c:2129 [inline] __se_sys_sendto net/socket.c:2125 [inline] __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 1758fd4688eb ("ipv6: remove unnecessary dst_hold() in ip6_fragment()") Reported-by: syzbot+8c0ac31aa9681abb9e2d@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet Cc: Wei Wang Cc: Martin KaFai Lau Link: https://lore.kernel.org/r/20221206101351.2037285-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

dccp/tcp: Reset saddr on failure after inet6?_hash_connect().

2022-12-02T16:43:08+00:00

[ Upstream commit 77934dc6db0d2b111a8f2759e9ad2fb67f5cffa5 ] When connect() is called on a socket bound to the wildcard address, we change the socket's saddr to a local address. If the socket fails to connect() to the destination, we have to reset the saddr. However, when an error occurs after inet_hash6?_connect() in (dccp|tcp)_v[46]_conect(), we forget to reset saddr and leave the socket bound to the address. From the user's point of view, whether saddr is reset or not varies with errno. Let's fix this inconsistent behaviour. Note that after this patch, the repro [0] will trigger the WARN_ON() in inet_csk_get_port() again, but this patch is not buggy and rather fixes a bug papering over the bhash2's bug for which we need another fix. For the record, the repro causes -EADDRNOTAVAIL in inet_hash6_connect() by this sequence: s1 = socket() s1.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1) s1.bind(('127.0.0.1', 10000)) s1.sendto(b'hello', MSG_FASTOPEN, (('127.0.0.1', 10000))) # or s1.connect(('127.0.0.1', 10000)) s2 = socket() s2.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1) s2.bind(('0.0.0.0', 10000)) s2.connect(('127.0.0.1', 10000)) # -EADDRNOTAVAIL s2.listen(32) # WARN_ON(inet_csk(sk)->icsk_bind2_hash != tb2); [0]: https://syzkaller.appspot.com/bug?extid=015d756bbd1f8b5c8f09 Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6") Fixes: 7c657876b63c ("[DCCP]: Initial implementation") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Acked-by: Joanne Koong Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

xfrm: Fix ignored return value in xfrm6_init()

2022-12-02T16:43:07+00:00

[ Upstream commit 40781bfb836eda57d19c0baa37c7e72590e05fdc ] When IPv6 module initializing in xfrm6_init(), register_pernet_subsys() is possible to fail but its return value is ignored. If IPv6 initialization fails later and xfrm6_fini() is called, removing uninitialized list in xfrm6_net_ops will cause null-ptr-deref: KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 330 Comm: insmod RIP: 0010:unregister_pernet_operations+0xc9/0x450 Call Trace: unregister_pernet_subsys+0x31/0x3e xfrm6_fini+0x16/0x30 [ipv6] ip6_route_init+0xcd/0x128 [ipv6] inet6_init+0x29c/0x602 [ipv6] ... Fix it by catching the error return value of register_pernet_subsys(). Fixes: 8d068875caca ("xfrm: make gc_thresh configurable in all namespaces") Signed-off-by: Chen Zhongjin Reviewed-by: Leon Romanovsky Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

xfrm: replay: Fix ESN wrap around for GSO

2022-12-02T16:43:02+00:00

[ Upstream commit 4b549ccce941798703f159b227aa28c716aa78fa ] When using GSO it can happen that the wrong seq_hi is used for the last packets before the wrap around. This can lead to double usage of a sequence number. To avoid this, we should serialize this last GSO packet. Fixes: d7dbefc45cf5 ("xfrm: Add xfrm_replay_overflow functions for offloading") Co-developed-by: Steffen Klassert Signed-off-by: Christian Langrock Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network

2022-11-16T09:03:55+00:00

[ Upstream commit c23fb2c82267638f9d206cb96bb93e1f93ad7828 ] When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved remained uninitialized, resulting in a 1-byte infoleak: BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841 __netdev_start_xmit ./include/linux/netdevice.h:4841 netdev_start_xmit ./include/linux/netdevice.h:4857 xmit_one net/core/dev.c:3590 dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606 __dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256 dev_queue_xmit ./include/linux/netdevice.h:3009 __netlink_deliver_tap_skb net/netlink/af_netlink.c:307 __netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325 netlink_deliver_tap net/netlink/af_netlink.c:338 __netlink_sendskb net/netlink/af_netlink.c:1263 netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272 netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360 nlmsg_unicast ./include/net/netlink.h:1061 rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758 ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628 rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 ... Uninit was created at: slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742 slab_alloc_node mm/slub.c:3398 __kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:954 __kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:437 __alloc_skb+0x27a/0xab0 net/core/skbuff.c:509 alloc_skb ./include/linux/skbuff.h:1267 nlmsg_new ./include/net/netlink.h:964 ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608 rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082 netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540 rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109 netlink_unicast_kernel net/netlink/af_netlink.c:1319 netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345 netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921 ... This patch ensures that the reserved field is always initialized. Reported-by: syzbot+3553517af6020c4f2813f1003fe76ef3cbffe98d@syzkaller.appspotmail.com Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") Signed-off-by: Alexander Potapenko Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin