<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv6, branch v5.4.223</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>inet: fully convert sk-&gt;sk_rx_dst to RCU rules</title>
<updated>2022-10-26T11:23:01+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-12-20T14:33:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c3bb4a7e8cbc984e1cdac0fe6af60e880214ed6e'/>
<id>c3bb4a7e8cbc984e1cdac0fe6af60e880214ed6e</id>
<content type='text'>
commit 8f905c0e7354ef261360fb7535ea079b1082c105 upstream.

syzbot reported various issues around early demux,
one being included in this changelog [1]

sk-&gt;sk_rx_dst is using RCU protection without clearly
documenting it.

And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()
are not following standard RCU rules.

[a]    dst_release(dst);
[b]    sk-&gt;sk_rx_dst = NULL;

They look wrong because a delete operation of RCU protected
pointer is supposed to clear the pointer before
the call_rcu()/synchronize_rcu() guarding actual memory freeing.

In some cases indeed, dst could be freed before [b] is done.

We could cheat by clearing sk_rx_dst before calling
dst_release(), but this seems the right time to stick
to standard RCU annotations and debugging facilities.

[1]
BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]
BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204

CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247
 __kasan_report mm/kasan/report.c:433 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
 dst_check include/net/dst.h:470 [inline]
 tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
 ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340
 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
 ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
 __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
 __netif_receive_skb_list net/core/dev.c:5608 [inline]
 netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
 gro_normal_list net/core/dev.c:5853 [inline]
 gro_normal_list net/core/dev.c:5849 [inline]
 napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
 virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
 __napi_poll+0xaf/0x440 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7177
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0033:0x7f5e972bfd57
Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e &lt;48&gt; 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73
RSP: 002b:00007fff8a413210 EFLAGS: 00000283
RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45
RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45
RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0
R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019
 &lt;/TASK&gt;

Allocated by task 13:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247
 dst_alloc+0x146/0x1f0 net/core/dst.c:92
 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
 ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:2340
 ip_route_input_rcu net/ipv4/route.c:2470 [inline]
 ip_route_input_noref+0x116/0x2a0 net/ipv4/route.c:2415
 ip_rcv_finish_core.constprop.0+0x288/0x1e80 net/ipv4/ip_input.c:354
 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
 ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
 __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
 __netif_receive_skb_list net/core/dev.c:5608 [inline]
 netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
 gro_normal_list net/core/dev.c:5853 [inline]
 gro_normal_list net/core/dev.c:5849 [inline]
 napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
 virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
 __napi_poll+0xaf/0x440 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7177
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Freed by task 13:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749
 slab_free mm/slub.c:3513 [inline]
 kmem_cache_free+0xbd/0x5d0 mm/slub.c:3530
 dst_destroy+0x2d6/0x3f0 net/core/dst.c:127
 rcu_do_batch kernel/rcu/tree.c:2506 [inline]
 rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2741
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Last potentially related work creation:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xf5/0x120 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2985 [inline]
 call_rcu+0xb1/0x740 kernel/rcu/tree.c:3065
 dst_release net/core/dst.c:177 [inline]
 dst_release+0x79/0xe0 net/core/dst.c:167
 tcp_v4_do_rcv+0x612/0x8d0 net/ipv4/tcp_ipv4.c:1712
 sk_backlog_rcv include/net/sock.h:1030 [inline]
 __release_sock+0x134/0x3b0 net/core/sock.c:2768
 release_sock+0x54/0x1b0 net/core/sock.c:3300
 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1441
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_write_iter+0x289/0x3c0 net/socket.c:1057
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write+0x429/0x660 fs/read_write.c:503
 vfs_write+0x7cd/0xae0 fs/read_write.c:590
 ksys_write+0x1ee/0x250 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88807f1cb700
 which belongs to the cache ip_dst_cache of size 176
The buggy address is located 58 bytes inside of
 176-byte region [ffff88807f1cb700, ffff88807f1cb7b0)
The buggy address belongs to the page:
page:ffffea0001fc72c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f1cb
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 dead000000000100 dead000000000122 ffff8881413bb780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
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 5, ts 108466983062, free_ts 108048976062
 prep_new_page mm/page_alloc.c:2418 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369
 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
 alloc_slab_page mm/slub.c:1793 [inline]
 allocate_slab mm/slub.c:1930 [inline]
 new_slab+0x32d/0x4a0 mm/slub.c:1993
 ___slab_alloc+0x918/0xfe0 mm/slub.c:3022
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109
 slab_alloc_node mm/slub.c:3200 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3247
 dst_alloc+0x146/0x1f0 net/core/dst.c:92
 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
 __mkroute_output net/ipv4/route.c:2564 [inline]
 ip_route_output_key_hash_rcu+0x921/0x2d00 net/ipv4/route.c:2791
 ip_route_output_key_hash+0x18b/0x300 net/ipv4/route.c:2619
 __ip_route_output_key include/net/route.h:126 [inline]
 ip_route_output_flow+0x23/0x150 net/ipv4/route.c:2850
 ip_route_output_key include/net/route.h:142 [inline]
 geneve_get_v4_rt+0x3a6/0x830 drivers/net/geneve.c:809
 geneve_xmit_skb drivers/net/geneve.c:899 [inline]
 geneve_xmit+0xc4a/0x3540 drivers/net/geneve.c:1082
 __netdev_start_xmit include/linux/netdevice.h:4994 [inline]
 netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 xmit_one net/core/dev.c:3590 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606
 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3309 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3388
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6078
 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2575
 mld_newpack+0x1df/0x770 net/ipv6/mcast.c:1754
 add_grhead+0x265/0x330 net/ipv6/mcast.c:1857
 add_grec+0x1053/0x14e0 net/ipv6/mcast.c:1995
 mld_send_initial_cr.part.0+0xf6/0x230 net/ipv6/mcast.c:2242
 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline]
 mld_dad_work+0x1d3/0x690 net/ipv6/mcast.c:2268
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445

Memory state around the buggy address:
 ffff88807f1cb600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807f1cb680: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
&gt;ffff88807f1cb700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88807f1cb780: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
 ffff88807f1cb800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20211220143330.680945-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[cmllamas: fixed trivial merge conflict]
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8f905c0e7354ef261360fb7535ea079b1082c105 upstream.

syzbot reported various issues around early demux,
one being included in this changelog [1]

sk-&gt;sk_rx_dst is using RCU protection without clearly
documenting it.

And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()
are not following standard RCU rules.

[a]    dst_release(dst);
[b]    sk-&gt;sk_rx_dst = NULL;

They look wrong because a delete operation of RCU protected
pointer is supposed to clear the pointer before
the call_rcu()/synchronize_rcu() guarding actual memory freeing.

In some cases indeed, dst could be freed before [b] is done.

We could cheat by clearing sk_rx_dst before calling
dst_release(), but this seems the right time to stick
to standard RCU annotations and debugging facilities.

[1]
BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]
BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204

CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 &lt;TASK&gt;
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247
 __kasan_report mm/kasan/report.c:433 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
 dst_check include/net/dst.h:470 [inline]
 tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
 ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340
 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
 ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
 __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
 __netif_receive_skb_list net/core/dev.c:5608 [inline]
 netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
 gro_normal_list net/core/dev.c:5853 [inline]
 gro_normal_list net/core/dev.c:5849 [inline]
 napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
 virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
 __napi_poll+0xaf/0x440 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7177
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0033:0x7f5e972bfd57
Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e &lt;48&gt; 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73
RSP: 002b:00007fff8a413210 EFLAGS: 00000283
RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45
RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45
RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0
R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019
 &lt;/TASK&gt;

Allocated by task 13:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247
 dst_alloc+0x146/0x1f0 net/core/dst.c:92
 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
 ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:2340
 ip_route_input_rcu net/ipv4/route.c:2470 [inline]
 ip_route_input_noref+0x116/0x2a0 net/ipv4/route.c:2415
 ip_rcv_finish_core.constprop.0+0x288/0x1e80 net/ipv4/ip_input.c:354
 ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
 ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
 ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
 __netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
 __netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
 __netif_receive_skb_list net/core/dev.c:5608 [inline]
 netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
 gro_normal_list net/core/dev.c:5853 [inline]
 gro_normal_list net/core/dev.c:5849 [inline]
 napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
 virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
 virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
 __napi_poll+0xaf/0x440 net/core/dev.c:7023
 napi_poll net/core/dev.c:7090 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7177
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Freed by task 13:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749
 slab_free mm/slub.c:3513 [inline]
 kmem_cache_free+0xbd/0x5d0 mm/slub.c:3530
 dst_destroy+0x2d6/0x3f0 net/core/dst.c:127
 rcu_do_batch kernel/rcu/tree.c:2506 [inline]
 rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2741
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Last potentially related work creation:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xf5/0x120 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2985 [inline]
 call_rcu+0xb1/0x740 kernel/rcu/tree.c:3065
 dst_release net/core/dst.c:177 [inline]
 dst_release+0x79/0xe0 net/core/dst.c:167
 tcp_v4_do_rcv+0x612/0x8d0 net/ipv4/tcp_ipv4.c:1712
 sk_backlog_rcv include/net/sock.h:1030 [inline]
 __release_sock+0x134/0x3b0 net/core/sock.c:2768
 release_sock+0x54/0x1b0 net/core/sock.c:3300
 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1441
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_write_iter+0x289/0x3c0 net/socket.c:1057
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write+0x429/0x660 fs/read_write.c:503
 vfs_write+0x7cd/0xae0 fs/read_write.c:590
 ksys_write+0x1ee/0x250 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88807f1cb700
 which belongs to the cache ip_dst_cache of size 176
The buggy address is located 58 bytes inside of
 176-byte region [ffff88807f1cb700, ffff88807f1cb7b0)
The buggy address belongs to the page:
page:ffffea0001fc72c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f1cb
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 dead000000000100 dead000000000122 ffff8881413bb780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
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 5, ts 108466983062, free_ts 108048976062
 prep_new_page mm/page_alloc.c:2418 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369
 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
 alloc_slab_page mm/slub.c:1793 [inline]
 allocate_slab mm/slub.c:1930 [inline]
 new_slab+0x32d/0x4a0 mm/slub.c:1993
 ___slab_alloc+0x918/0xfe0 mm/slub.c:3022
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109
 slab_alloc_node mm/slub.c:3200 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3247
 dst_alloc+0x146/0x1f0 net/core/dst.c:92
 rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
 __mkroute_output net/ipv4/route.c:2564 [inline]
 ip_route_output_key_hash_rcu+0x921/0x2d00 net/ipv4/route.c:2791
 ip_route_output_key_hash+0x18b/0x300 net/ipv4/route.c:2619
 __ip_route_output_key include/net/route.h:126 [inline]
 ip_route_output_flow+0x23/0x150 net/ipv4/route.c:2850
 ip_route_output_key include/net/route.h:142 [inline]
 geneve_get_v4_rt+0x3a6/0x830 drivers/net/geneve.c:809
 geneve_xmit_skb drivers/net/geneve.c:899 [inline]
 geneve_xmit+0xc4a/0x3540 drivers/net/geneve.c:1082
 __netdev_start_xmit include/linux/netdevice.h:4994 [inline]
 netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 xmit_one net/core/dev.c:3590 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606
 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3309 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3388
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6078
 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2575
 mld_newpack+0x1df/0x770 net/ipv6/mcast.c:1754
 add_grhead+0x265/0x330 net/ipv6/mcast.c:1857
 add_grec+0x1053/0x14e0 net/ipv6/mcast.c:1995
 mld_send_initial_cr.part.0+0xf6/0x230 net/ipv6/mcast.c:2242
 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline]
 mld_dad_work+0x1d3/0x690 net/ipv6/mcast.c:2268
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445

Memory state around the buggy address:
 ffff88807f1cb600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807f1cb680: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
&gt;ffff88807f1cb700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88807f1cb780: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
 ffff88807f1cb800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20211220143330.680945-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[cmllamas: fixed trivial merge conflict]
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: nft_fib: Fix for rpath check with VRF devices</title>
<updated>2022-10-26T11:22:25+00:00</updated>
<author>
<name>Phil Sutter</name>
<email>phil@nwl.cc</email>
</author>
<published>2022-09-21T11:07:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=60a7496b40e8e81025c963c5dcd7dd6bffdbaa99'/>
<id>60a7496b40e8e81025c963c5dcd7dd6bffdbaa99</id>
<content type='text'>
[ Upstream commit 2a8a7c0eaa8747c16aa4a48d573aa920d5c00a5c ]

Analogous to commit b575b24b8eee3 ("netfilter: Fix rpfilter
dropping vrf packets by mistake") but for nftables fib expression:
Add special treatment of VRF devices so that typical reverse path
filtering via 'fib saddr . iif oif' expression works as expected.

Fixes: f6d0cbcf09c50 ("netfilter: nf_tables: add fib expression")
Signed-off-by: Phil Sutter &lt;phil@nwl.cc&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2a8a7c0eaa8747c16aa4a48d573aa920d5c00a5c ]

Analogous to commit b575b24b8eee3 ("netfilter: Fix rpfilter
dropping vrf packets by mistake") but for nftables fib expression:
Add special treatment of VRF devices so that typical reverse path
filtering via 'fib saddr . iif oif' expression works as expected.

Fixes: f6d0cbcf09c50 ("netfilter: nf_tables: add fib expression")
Signed-off-by: Phil Sutter &lt;phil@nwl.cc&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: sr: fix out-of-bounds read when setting HMAC data.</title>
<updated>2022-09-15T10:04:55+00:00</updated>
<author>
<name>David Lebrun</name>
<email>dlebrun@google.com</email>
</author>
<published>2022-09-02T09:45:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3df71e11a4773d775c3633c44319f7acdb89011c'/>
<id>3df71e11a4773d775c3633c44319f7acdb89011c</id>
<content type='text'>
[ Upstream commit 84a53580c5d2138c7361c7c3eea5b31827e63b35 ]

The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
Segment Routing Headers. This configuration is realised via netlink through
four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
length of the SECRET attribute, it is possible to provide invalid combinations
(e.g., secret = "", secretlen = 64). This case is not checked in the code and
with an appropriately crafted netlink message, an out-of-bounds read of up
to 64 bytes (max secret length) can occur past the skb end pointer and into
skb_shared_info:

Breakpoint 1, seg6_genl_sethmac (skb=&lt;optimized out&gt;, info=&lt;optimized out&gt;) at net/ipv6/seg6.c:208
208		memcpy(hinfo-&gt;secret, secret, slen);
(gdb) bt
 #0  seg6_genl_sethmac (skb=&lt;optimized out&gt;, info=&lt;optimized out&gt;) at net/ipv6/seg6.c:208
 #1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 &lt;init_net&gt;, family=&lt;optimized out&gt;,
    family=&lt;optimized out&gt;) at net/netlink/genetlink.c:731
 #2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
    family=0xffffffff82fef6c0 &lt;seg6_genl_family&gt;) at net/netlink/genetlink.c:775
 #3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
 #4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 &lt;genl_rcv_msg&gt;)
    at net/netlink/af_netlink.c:2501
 #5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
 #6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
    at net/netlink/af_netlink.c:1319
 #7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=&lt;optimized out&gt;)
    at net/netlink/af_netlink.c:1345
 #8  0xffffffff81dff9a4 in netlink_sendmsg (sock=&lt;optimized out&gt;, msg=0xffffc90000ba7e48, len=&lt;optimized out&gt;) at net/netlink/af_netlink.c:1921
...
(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)-&gt;head + ((struct sk_buff *)0xffff88800b1f9f00)-&gt;end
$1 = 0xffff88800b1b76c0
(gdb) p/x secret
$2 = 0xffff88800b1b76c0
(gdb) p slen
$3 = 64 '@'

The OOB data can then be read back from userspace by dumping HMAC state. This
commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
SECRET.

Reported-by: Lucas Leong &lt;wmliang.tw@gmail.com&gt;
Tested: verified that EINVAL is correctly returned when secretlen &gt; len(secret)
Fixes: 4f4853dc1c9c1 ("ipv6: sr: implement API to control SR HMAC structure")
Signed-off-by: David Lebrun &lt;dlebrun@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 84a53580c5d2138c7361c7c3eea5b31827e63b35 ]

The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
Segment Routing Headers. This configuration is realised via netlink through
four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
length of the SECRET attribute, it is possible to provide invalid combinations
(e.g., secret = "", secretlen = 64). This case is not checked in the code and
with an appropriately crafted netlink message, an out-of-bounds read of up
to 64 bytes (max secret length) can occur past the skb end pointer and into
skb_shared_info:

Breakpoint 1, seg6_genl_sethmac (skb=&lt;optimized out&gt;, info=&lt;optimized out&gt;) at net/ipv6/seg6.c:208
208		memcpy(hinfo-&gt;secret, secret, slen);
(gdb) bt
 #0  seg6_genl_sethmac (skb=&lt;optimized out&gt;, info=&lt;optimized out&gt;) at net/ipv6/seg6.c:208
 #1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 &lt;init_net&gt;, family=&lt;optimized out&gt;,
    family=&lt;optimized out&gt;) at net/netlink/genetlink.c:731
 #2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
    family=0xffffffff82fef6c0 &lt;seg6_genl_family&gt;) at net/netlink/genetlink.c:775
 #3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
 #4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 &lt;genl_rcv_msg&gt;)
    at net/netlink/af_netlink.c:2501
 #5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
 #6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
    at net/netlink/af_netlink.c:1319
 #7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=&lt;optimized out&gt;)
    at net/netlink/af_netlink.c:1345
 #8  0xffffffff81dff9a4 in netlink_sendmsg (sock=&lt;optimized out&gt;, msg=0xffffc90000ba7e48, len=&lt;optimized out&gt;) at net/netlink/af_netlink.c:1921
...
(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)-&gt;head + ((struct sk_buff *)0xffff88800b1f9f00)-&gt;end
$1 = 0xffff88800b1b76c0
(gdb) p/x secret
$2 = 0xffff88800b1b76c0
(gdb) p slen
$3 = 64 '@'

The OOB data can then be read back from userspace by dumping HMAC state. This
commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
SECRET.

Reported-by: Lucas Leong &lt;wmliang.tw@gmail.com&gt;
Tested: verified that EINVAL is correctly returned when secretlen &gt; len(secret)
Fixes: 4f4853dc1c9c1 ("ipv6: sr: implement API to control SR HMAC structure")
Signed-off-by: David Lebrun &lt;dlebrun@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: ping6: Fix memleak in ipv6_renew_options().</title>
<updated>2022-08-03T09:59:39+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-28T01:22:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=421e5dd1f12e56b1418d1525b536ff04250df373'/>
<id>421e5dd1f12e56b1418d1525b536ff04250df373</id>
<content type='text'>
commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.

When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk-&gt;sk_prot-&gt;destroy().  As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.

    struct ipv6_sr_hdr *hdr;
    char data[24] = {0};
    int fd;

    hdr = (struct ipv6_sr_hdr *)data;
    hdr-&gt;hdrlen = 2;
    hdr-&gt;type = IPV6_SRCRT_TYPE_4;

    fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
    setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
    close(fd);

To fix memory leaks, let's add a destroy function.

Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range.  The default value is [1, 0] so that no
GID meets the condition (1 &lt;= GID &lt;= 0).  Thus, the local DoS does
not succeed until we change the default value.  However, at least
Ubuntu/Fedora/RHEL loosen it.

    $ cat /usr/lib/sysctl.d/50-default.conf
    ...
    -net.ipv4.ping_group_range = 0 2147483647

Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.

  setsockopt
      IPV6_ADDRFORM (inet6_sk(sk)-&gt;pktoptions)
      IPV6_RECVPATHMTU (inet6_sk(sk)-&gt;rxpmtu)
      IPV6_HOPOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDRDSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDR (inet6_sk(sk)-&gt;opt)
      IPV6_DSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_2292PKTOPTIONS (inet6_sk(sk)-&gt;opt)

  getsockopt
      IPV6_FLOWLABEL_MGR (inet6_sk(sk)-&gt;ipv6_fl_list)

For the record, I left a different splat with syzbot's one.

  unreferenced object 0xffff888006270c60 (size 96):
    comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
    hex dump (first 32 bytes):
      01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00  ....D...........
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [&lt;00000000f6bc7ea9&gt;] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
      [&lt;000000006d699550&gt;] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
      [&lt;00000000c3c3b1f5&gt;] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
      [&lt;000000007096a025&gt;] __sys_setsockopt (net/socket.c:2254)
      [&lt;000000003a8ff47b&gt;] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
      [&lt;000000007c409dcb&gt;] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
      [&lt;00000000e939c4a9&gt;] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176

Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.")
Reported-by: syzbot+a8430774139ec3ab7176@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta &lt;ayudutta@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220728012220.46918-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.

When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk-&gt;sk_prot-&gt;destroy().  As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.

    struct ipv6_sr_hdr *hdr;
    char data[24] = {0};
    int fd;

    hdr = (struct ipv6_sr_hdr *)data;
    hdr-&gt;hdrlen = 2;
    hdr-&gt;type = IPV6_SRCRT_TYPE_4;

    fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
    setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
    close(fd);

To fix memory leaks, let's add a destroy function.

Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range.  The default value is [1, 0] so that no
GID meets the condition (1 &lt;= GID &lt;= 0).  Thus, the local DoS does
not succeed until we change the default value.  However, at least
Ubuntu/Fedora/RHEL loosen it.

    $ cat /usr/lib/sysctl.d/50-default.conf
    ...
    -net.ipv4.ping_group_range = 0 2147483647

Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.

  setsockopt
      IPV6_ADDRFORM (inet6_sk(sk)-&gt;pktoptions)
      IPV6_RECVPATHMTU (inet6_sk(sk)-&gt;rxpmtu)
      IPV6_HOPOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDRDSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_RTHDR (inet6_sk(sk)-&gt;opt)
      IPV6_DSTOPTS (inet6_sk(sk)-&gt;opt)
      IPV6_2292PKTOPTIONS (inet6_sk(sk)-&gt;opt)

  getsockopt
      IPV6_FLOWLABEL_MGR (inet6_sk(sk)-&gt;ipv6_fl_list)

For the record, I left a different splat with syzbot's one.

  unreferenced object 0xffff888006270c60 (size 96):
    comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
    hex dump (first 32 bytes):
      01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00  ....D...........
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [&lt;00000000f6bc7ea9&gt;] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
      [&lt;000000006d699550&gt;] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
      [&lt;00000000c3c3b1f5&gt;] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
      [&lt;000000007096a025&gt;] __sys_setsockopt (net/socket.c:2254)
      [&lt;000000003a8ff47b&gt;] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
      [&lt;000000007c409dcb&gt;] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
      [&lt;00000000e939c4a9&gt;] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176

Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.")
Reported-by: syzbot+a8430774139ec3ab7176@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta &lt;ayudutta@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20220728012220.46918-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: Fix data-races around sysctl_tcp_syncookies.</title>
<updated>2022-07-29T15:14:13+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-15T17:17:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b222de2560ab56ca30452d35b7cc0fdd7be98ed2'/>
<id>b222de2560ab56ca30452d35b7cc0fdd7be98ed2</id>
<content type='text'>
[ Upstream commit f2e383b5bb6bbc60a0b94b87b3e49a2b1aefd11e ]

While reading sysctl_tcp_syncookies, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f2e383b5bb6bbc60a0b94b87b3e49a2b1aefd11e ]

While reading sysctl_tcp_syncookies, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ip: Fix data-races around sysctl_ip_no_pmtu_disc.</title>
<updated>2022-07-29T15:14:10+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.com</email>
</author>
<published>2022-07-13T20:51:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5af6d9226376fbd0dba6876139385e770342726f'/>
<id>5af6d9226376fbd0dba6876139385e770342726f</id>
<content type='text'>
[ Upstream commit 0968d2a441bf6afb551fd99e60fa65ed67068963 ]

While reading sysctl_ip_no_pmtu_disc, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0968d2a441bf6afb551fd99e60fa65ed67068963 ]

While reading sysctl_ip_no_pmtu_disc, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>seg6: fix skb checksum in SRv6 End.B6 and End.B6.Encaps behaviors</title>
<updated>2022-07-21T18:59:23+00:00</updated>
<author>
<name>Andrea Mayer</name>
<email>andrea.mayer@uniroma2.it</email>
</author>
<published>2022-07-12T17:58:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=de7849d9de1df52fcade7032c49537c603a67873'/>
<id>de7849d9de1df52fcade7032c49537c603a67873</id>
<content type='text'>
[ Upstream commit f048880fc77058d864aff5c674af7918b30f312a ]

The SRv6 End.B6 and End.B6.Encaps behaviors rely on functions
seg6_do_srh_{encap,inline}() to, respectively: i) encapsulate the
packet within an outer IPv6 header with the specified Segment Routing
Header (SRH); ii) insert the specified SRH directly after the IPv6
header of the packet.

This patch removes the initialization of the IPv6 header payload length
from the input_action_end_b6{_encap}() functions, as it is now handled
properly by seg6_do_srh_{encap,inline}() to avoid corruption of the skb
checksum.

Fixes: 140f04c33bbc ("ipv6: sr: implement several seg6local actions")
Signed-off-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f048880fc77058d864aff5c674af7918b30f312a ]

The SRv6 End.B6 and End.B6.Encaps behaviors rely on functions
seg6_do_srh_{encap,inline}() to, respectively: i) encapsulate the
packet within an outer IPv6 header with the specified Segment Routing
Header (SRH); ii) insert the specified SRH directly after the IPv6
header of the packet.

This patch removes the initialization of the IPv6 header payload length
from the input_action_end_b6{_encap}() functions, as it is now handled
properly by seg6_do_srh_{encap,inline}() to avoid corruption of the skb
checksum.

Fixes: 140f04c33bbc ("ipv6: sr: implement several seg6local actions")
Signed-off-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>seg6: fix skb checksum evaluation in SRH encapsulation/insertion</title>
<updated>2022-07-21T18:59:23+00:00</updated>
<author>
<name>Andrea Mayer</name>
<email>andrea.mayer@uniroma2.it</email>
</author>
<published>2022-07-12T17:58:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=487f0f77f1cdedc66ed79474990c814541c25ff1'/>
<id>487f0f77f1cdedc66ed79474990c814541c25ff1</id>
<content type='text'>
[ Upstream commit df8386d13ea280d55beee1b95f61a59234a3798b ]

Support for SRH encapsulation and insertion was introduced with
commit 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and
injection with lwtunnels"), through the seg6_do_srh_encap() and
seg6_do_srh_inline() functions, respectively.
The former encapsulates the packet in an outer IPv6 header along with
the SRH, while the latter inserts the SRH between the IPv6 header and
the payload. Then, the headers are initialized/updated according to the
operating mode (i.e., encap/inline).
Finally, the skb checksum is calculated to reflect the changes applied
to the headers.

The IPv6 payload length ('payload_len') is not initialized
within seg6_do_srh_{inline,encap}() but is deferred in seg6_do_srh(), i.e.
the caller of seg6_do_srh_{inline,encap}().
However, this operation invalidates the skb checksum, since the
'payload_len' is updated only after the checksum is evaluated.

To solve this issue, the initialization of the IPv6 payload length is
moved from seg6_do_srh() directly into the seg6_do_srh_{inline,encap}()
functions and before the skb checksum update takes place.

Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Link: https://lore.kernel.org/all/20220705190727.69d532417be7438b15404ee1@uniroma2.it
Signed-off-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit df8386d13ea280d55beee1b95f61a59234a3798b ]

Support for SRH encapsulation and insertion was introduced with
commit 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and
injection with lwtunnels"), through the seg6_do_srh_encap() and
seg6_do_srh_inline() functions, respectively.
The former encapsulates the packet in an outer IPv6 header along with
the SRH, while the latter inserts the SRH between the IPv6 header and
the payload. Then, the headers are initialized/updated according to the
operating mode (i.e., encap/inline).
Finally, the skb checksum is calculated to reflect the changes applied
to the headers.

The IPv6 payload length ('payload_len') is not initialized
within seg6_do_srh_{inline,encap}() but is deferred in seg6_do_srh(), i.e.
the caller of seg6_do_srh_{inline,encap}().
However, this operation invalidates the skb checksum, since the
'payload_len' is updated only after the checksum is evaluated.

To solve this issue, the initialization of the IPv6 payload length is
moved from seg6_do_srh() directly into the seg6_do_srh_{inline,encap}()
functions and before the skb checksum update takes place.

Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Link: https://lore.kernel.org/all/20220705190727.69d532417be7438b15404ee1@uniroma2.it
Signed-off-by: Andrea Mayer &lt;andrea.mayer@uniroma2.it&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>esp: limit skb_page_frag_refill use to a single page</title>
<updated>2022-07-12T14:30:45+00:00</updated>
<author>
<name>Sabrina Dubroca</name>
<email>sd@queasysnail.net</email>
</author>
<published>2022-04-13T08:10:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3defefd22ad5fbbe639b6157fb7e6311b2bf333d'/>
<id>3defefd22ad5fbbe639b6157fb7e6311b2bf333d</id>
<content type='text'>
commit 5bd8baab087dff657e05387aee802e70304cc813 upstream.

Commit ebe48d368e97 ("esp: Fix possible buffer overflow in ESP
transformation") tried to fix skb_page_frag_refill usage in ESP by
capping allocsize to 32k, but that doesn't completely solve the issue,
as skb_page_frag_refill may return a single page. If that happens, we
will write out of bounds, despite the check introduced in the previous
patch.

This patch forces COW in cases where we would end up calling
skb_page_frag_refill with a size larger than a page (first in
esp_output_head with tailen, then in esp_output_tail with
skb-&gt;data_len).

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5bd8baab087dff657e05387aee802e70304cc813 upstream.

Commit ebe48d368e97 ("esp: Fix possible buffer overflow in ESP
transformation") tried to fix skb_page_frag_refill usage in ESP by
capping allocsize to 32k, but that doesn't completely solve the issue,
as skb_page_frag_refill may return a single page. If that happens, we
will write out of bounds, despite the check introduced in the previous
patch.

This patch forces COW in cases where we would end up calling
skb_page_frag_refill with a size larger than a page (first in
esp_output_head with tailen, then in esp_output_tail with
skb-&gt;data_len).

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6/sit: fix ipip6_tunnel_get_prl return value</title>
<updated>2022-07-07T15:36:51+00:00</updated>
<author>
<name>katrinzhou</name>
<email>katrinzhou@tencent.com</email>
</author>
<published>2022-06-28T03:50:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7b6bffcfb9d34dc4b279f8fb7b72e9182acb2a08'/>
<id>7b6bffcfb9d34dc4b279f8fb7b72e9182acb2a08</id>
<content type='text'>
commit adabdd8f6acabc0c3fdbba2e7f5a2edd9c5ef22d upstream.

When kcalloc fails, ipip6_tunnel_get_prl() should return -ENOMEM.
Move the position of label "out" to return correctly.

Addresses-Coverity: ("Unused value")
Fixes: 300aaeeaab5f ("[IPV6] SIT: Add SIOCGETPRL ioctl to get/dump PRL.")
Signed-off-by: katrinzhou &lt;katrinzhou@tencent.com&gt;
Reviewed-by: Eric Dumazet&lt;edumazet@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220628035030.1039171-1-zys.zljxml@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit adabdd8f6acabc0c3fdbba2e7f5a2edd9c5ef22d upstream.

When kcalloc fails, ipip6_tunnel_get_prl() should return -ENOMEM.
Move the position of label "out" to return correctly.

Addresses-Coverity: ("Unused value")
Fixes: 300aaeeaab5f ("[IPV6] SIT: Add SIOCGETPRL ioctl to get/dump PRL.")
Signed-off-by: katrinzhou &lt;katrinzhou@tencent.com&gt;
Reviewed-by: Eric Dumazet&lt;edumazet@google.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20220628035030.1039171-1-zys.zljxml@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
