linux-stable.git/net/ipv4, branch v4.9.313 Linux kernel stable tree net: igmp: respect RCU rules in ip_mc_source() and ip_mc_msfilter() 2022-05-12T10:14:58+00:00 Eric Dumazet edumazet@google.com 2022-04-29T15:42:57+00:00 7815943e670c52997072a7561d369cab241a7713 commit dba5bdd57bea587ea4f0b79b03c71135f84a7e8b upstream. syzbot reported an UAF in ip_mc_sf_allow() [1] Whenever RCU protected list replaces an object, the pointer to the new object needs to be updated _before_ the call to kfree_rcu() or call_rcu() Because kfree_rcu(ptr, rcu) got support for NULL ptr only recently in commit 12edff045bc6 ("rcu: Make kfree_rcu() ignore NULL pointers"), I chose to use the conditional to make sure stable backports won't miss this detail. if (psl) kfree_rcu(psl, rcu); net/ipv6/mcast.c has similar issues, addressed in a separate patch. [1] BUG: KASAN: use-after-free in ip_mc_sf_allow+0x6bb/0x6d0 net/ipv4/igmp.c:2655 Read of size 4 at addr ffff88807d37b904 by task syz-executor.5/908 CPU: 0 PID: 908 Comm: syz-executor.5 Not tainted 5.18.0-rc4-syzkaller-00064-g8f4dd16603ce #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 ip_mc_sf_allow+0x6bb/0x6d0 net/ipv4/igmp.c:2655 raw_v4_input net/ipv4/raw.c:190 [inline] raw_local_deliver+0x4d1/0xbe0 net/ipv4/raw.c:218 ip_protocol_deliver_rcu+0xcf/0xb30 net/ipv4/ip_input.c:193 ip_local_deliver_finish+0x2ee/0x4c0 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1b3/0x200 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x1cb/0x2f0 net/ipv4/ip_input.c:437 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xaa/0xd0 net/ipv4/ip_input.c:556 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5405 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5519 netif_receive_skb_internal net/core/dev.c:5605 [inline] netif_receive_skb+0x13e/0x8e0 net/core/dev.c:5664 tun_rx_batched.isra.0+0x460/0x720 drivers/net/tun.c:1534 tun_get_user+0x28b7/0x3e30 drivers/net/tun.c:1985 tun_chr_write_iter+0xdb/0x200 drivers/net/tun.c:2015 call_write_iter include/linux/fs.h:2050 [inline] new_sync_write+0x38a/0x560 fs/read_write.c:504 vfs_write+0x7c0/0xac0 fs/read_write.c:591 ksys_write+0x127/0x250 fs/read_write.c:644 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 RIP: 0033:0x7f3f12c3bbff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48 RSP: 002b:00007f3f13ea9130 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3f12d9bf60 RCX: 00007f3f12c3bbff RDX: 0000000000000036 RSI: 0000000020002ac0 RDI: 00000000000000c8 RBP: 00007f3f12ce308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000036 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fffb68dd79f R14: 00007f3f13ea9300 R15: 0000000000022000 </TASK> Allocated by task 908: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524 kasan_kmalloc include/linux/kasan.h:234 [inline] __do_kmalloc mm/slab.c:3710 [inline] __kmalloc+0x209/0x4d0 mm/slab.c:3719 kmalloc include/linux/slab.h:586 [inline] sock_kmalloc net/core/sock.c:2501 [inline] sock_kmalloc+0xb5/0x100 net/core/sock.c:2492 ip_mc_source+0xba2/0x1100 net/ipv4/igmp.c:2392 do_ip_setsockopt net/ipv4/ip_sockglue.c:1296 [inline] ip_setsockopt+0x2312/0x3ab0 net/ipv4/ip_sockglue.c:1432 raw_setsockopt+0x274/0x2c0 net/ipv4/raw.c:861 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188 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 Freed by task 753: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x13d/0x180 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] __cache_free mm/slab.c:3439 [inline] kmem_cache_free_bulk+0x69/0x460 mm/slab.c:3774 kfree_bulk include/linux/slab.h:437 [inline] kfree_rcu_work+0x51c/0xa10 kernel/rcu/tree.c:3318 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3595 ip_mc_msfilter+0x712/0xb60 net/ipv4/igmp.c:2510 do_ip_setsockopt net/ipv4/ip_sockglue.c:1257 [inline] ip_setsockopt+0x32e1/0x3ab0 net/ipv4/ip_sockglue.c:1432 raw_setsockopt+0x274/0x2c0 net/ipv4/raw.c:861 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188 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 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348 call_rcu+0x99/0x790 kernel/rcu/tree.c:3074 mpls_dev_notify+0x552/0x8a0 net/mpls/af_mpls.c:1656 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1938 call_netdevice_notifiers_extack net/core/dev.c:1976 [inline] call_netdevice_notifiers net/core/dev.c:1990 [inline] unregister_netdevice_many+0x92e/0x1890 net/core/dev.c:10751 default_device_exit_batch+0x449/0x590 net/core/dev.c:11245 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff88807d37b900 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 4 bytes inside of 64-byte region [ffff88807d37b900, ffff88807d37b940) The buggy address belongs to the physical page: page:ffffea0001f4dec0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807d37b180 pfn:0x7d37b flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff888010c41340 ffffea0001c795c8 ffff888010c40200 raw: ffff88807d37b180 ffff88807d37b000 000000010000001f 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 0x342040(__GFP_IO|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 2963, tgid 2963 (udevd), ts 139732238007, free_ts 139730893262 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 __alloc_pages_node include/linux/gfp.h:587 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x350 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3309 [inline] __do_kmalloc mm/slab.c:3708 [inline] __kmalloc+0x3b3/0x4d0 mm/slab.c:3719 kmalloc include/linux/slab.h:586 [inline] kzalloc include/linux/slab.h:714 [inline] tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45 tomoyo_encode2 security/tomoyo/realpath.c:31 [inline] tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x186/0x620 security/tomoyo/realpath.c:288 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1350 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x16a/0x390 fs/stat.c:232 vfs_fstatat+0x8c/0xb0 fs/stat.c:255 __do_sys_newfstatat+0x91/0x110 fs/stat.c:425 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 __vunmap+0x85d/0xd30 mm/vmalloc.c:2667 __vfree+0x3c/0xd0 mm/vmalloc.c:2715 vfree+0x5a/0x90 mm/vmalloc.c:2746 __do_replace+0x16b/0x890 net/ipv6/netfilter/ip6_tables.c:1117 do_replace net/ipv6/netfilter/ip6_tables.c:1157 [inline] do_ip6t_set_ctl+0x90d/0xb90 net/ipv6/netfilter/ip6_tables.c:1639 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1026 tcp_setsockopt+0x136/0x2520 net/ipv4/tcp.c:3696 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188 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 Memory state around the buggy address: ffff88807d37b800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ffff88807d37b880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc >ffff88807d37b900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88807d37b980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88807d37ba00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc Fixes: c85bb41e9318 ("igmp: fix ip_mc_sf_allow race [v5]") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Flavio Leitner <fbl@sysclose.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit dba5bdd57bea587ea4f0b79b03c71135f84a7e8b upstream.

syzbot reported an UAF in ip_mc_sf_allow() [1]

Whenever RCU protected list replaces an object,
the pointer to the new object needs to be updated
_before_ the call to kfree_rcu() or call_rcu()

Because kfree_rcu(ptr, rcu) got support for NULL ptr
only recently in commit 12edff045bc6 ("rcu: Make kfree_rcu()
ignore NULL pointers"), I chose to use the conditional
to make sure stable backports won't miss this detail.

if (psl)
    kfree_rcu(psl, rcu);

net/ipv6/mcast.c has similar issues, addressed in a separate patch.

[1]
BUG: KASAN: use-after-free in ip_mc_sf_allow+0x6bb/0x6d0 net/ipv4/igmp.c:2655
Read of size 4 at addr ffff88807d37b904 by task syz-executor.5/908

CPU: 0 PID: 908 Comm: syz-executor.5 Not tainted 5.18.0-rc4-syzkaller-00064-g8f4dd16603ce #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313
 print_report mm/kasan/report.c:429 [inline]
 kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
 ip_mc_sf_allow+0x6bb/0x6d0 net/ipv4/igmp.c:2655
 raw_v4_input net/ipv4/raw.c:190 [inline]
 raw_local_deliver+0x4d1/0xbe0 net/ipv4/raw.c:218
 ip_protocol_deliver_rcu+0xcf/0xb30 net/ipv4/ip_input.c:193
 ip_local_deliver_finish+0x2ee/0x4c0 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip_local_deliver+0x1b3/0x200 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:461 [inline]
 ip_rcv_finish+0x1cb/0x2f0 net/ipv4/ip_input.c:437
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip_rcv+0xaa/0xd0 net/ipv4/ip_input.c:556
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5405
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5519
 netif_receive_skb_internal net/core/dev.c:5605 [inline]
 netif_receive_skb+0x13e/0x8e0 net/core/dev.c:5664
 tun_rx_batched.isra.0+0x460/0x720 drivers/net/tun.c:1534
 tun_get_user+0x28b7/0x3e30 drivers/net/tun.c:1985
 tun_chr_write_iter+0xdb/0x200 drivers/net/tun.c:2015
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write+0x38a/0x560 fs/read_write.c:504
 vfs_write+0x7c0/0xac0 fs/read_write.c:591
 ksys_write+0x127/0x250 fs/read_write.c:644
 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
RIP: 0033:0x7f3f12c3bbff
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48
RSP: 002b:00007f3f13ea9130 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3f12d9bf60 RCX: 00007f3f12c3bbff
RDX: 0000000000000036 RSI: 0000000020002ac0 RDI: 00000000000000c8
RBP: 00007f3f12ce308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000036 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fffb68dd79f R14: 00007f3f13ea9300 R15: 0000000000022000
 </TASK>

Allocated by task 908:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 ____kasan_kmalloc mm/kasan/common.c:515 [inline]
 ____kasan_kmalloc mm/kasan/common.c:474 [inline]
 __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524
 kasan_kmalloc include/linux/kasan.h:234 [inline]
 __do_kmalloc mm/slab.c:3710 [inline]
 __kmalloc+0x209/0x4d0 mm/slab.c:3719
 kmalloc include/linux/slab.h:586 [inline]
 sock_kmalloc net/core/sock.c:2501 [inline]
 sock_kmalloc+0xb5/0x100 net/core/sock.c:2492
 ip_mc_source+0xba2/0x1100 net/ipv4/igmp.c:2392
 do_ip_setsockopt net/ipv4/ip_sockglue.c:1296 [inline]
 ip_setsockopt+0x2312/0x3ab0 net/ipv4/ip_sockglue.c:1432
 raw_setsockopt+0x274/0x2c0 net/ipv4/raw.c:861
 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
 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

Freed by task 753:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free+0x13d/0x180 mm/kasan/common.c:328
 kasan_slab_free include/linux/kasan.h:200 [inline]
 __cache_free mm/slab.c:3439 [inline]
 kmem_cache_free_bulk+0x69/0x460 mm/slab.c:3774
 kfree_bulk include/linux/slab.h:437 [inline]
 kfree_rcu_work+0x51c/0xa10 kernel/rcu/tree.c:3318
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348
 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3595
 ip_mc_msfilter+0x712/0xb60 net/ipv4/igmp.c:2510
 do_ip_setsockopt net/ipv4/ip_sockglue.c:1257 [inline]
 ip_setsockopt+0x32e1/0x3ab0 net/ipv4/ip_sockglue.c:1432
 raw_setsockopt+0x274/0x2c0 net/ipv4/raw.c:861
 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
 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

Second to last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348
 call_rcu+0x99/0x790 kernel/rcu/tree.c:3074
 mpls_dev_notify+0x552/0x8a0 net/mpls/af_mpls.c:1656
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84
 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1938
 call_netdevice_notifiers_extack net/core/dev.c:1976 [inline]
 call_netdevice_notifiers net/core/dev.c:1990 [inline]
 unregister_netdevice_many+0x92e/0x1890 net/core/dev.c:10751
 default_device_exit_batch+0x449/0x590 net/core/dev.c:11245
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167
 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff88807d37b900
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 4 bytes inside of
 64-byte region [ffff88807d37b900, ffff88807d37b940)

The buggy address belongs to the physical page:
page:ffffea0001f4dec0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807d37b180 pfn:0x7d37b
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffff888010c41340 ffffea0001c795c8 ffff888010c40200
raw: ffff88807d37b180 ffff88807d37b000 000000010000001f 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 0x342040(__GFP_IO|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 2963, tgid 2963 (udevd), ts 139732238007, free_ts 139730893262
 prep_new_page mm/page_alloc.c:2441 [inline]
 get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408
 __alloc_pages_node include/linux/gfp.h:587 [inline]
 kmem_getpages mm/slab.c:1378 [inline]
 cache_grow_begin+0x75/0x350 mm/slab.c:2584
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957
 ____cache_alloc mm/slab.c:3040 [inline]
 ____cache_alloc mm/slab.c:3023 [inline]
 __do_cache_alloc mm/slab.c:3267 [inline]
 slab_alloc mm/slab.c:3309 [inline]
 __do_kmalloc mm/slab.c:3708 [inline]
 __kmalloc+0x3b3/0x4d0 mm/slab.c:3719
 kmalloc include/linux/slab.h:586 [inline]
 kzalloc include/linux/slab.h:714 [inline]
 tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45
 tomoyo_encode2 security/tomoyo/realpath.c:31 [inline]
 tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x186/0x620 security/tomoyo/realpath.c:288
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x140 security/security.c:1350
 vfs_getattr fs/stat.c:157 [inline]
 vfs_statx+0x16a/0x390 fs/stat.c:232
 vfs_fstatat+0x8c/0xb0 fs/stat.c:255
 __do_sys_newfstatat+0x91/0x110 fs/stat.c:425
 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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1356 [inline]
 free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406
 free_unref_page_prepare mm/page_alloc.c:3328 [inline]
 free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423
 __vunmap+0x85d/0xd30 mm/vmalloc.c:2667
 __vfree+0x3c/0xd0 mm/vmalloc.c:2715
 vfree+0x5a/0x90 mm/vmalloc.c:2746
 __do_replace+0x16b/0x890 net/ipv6/netfilter/ip6_tables.c:1117
 do_replace net/ipv6/netfilter/ip6_tables.c:1157 [inline]
 do_ip6t_set_ctl+0x90d/0xb90 net/ipv6/netfilter/ip6_tables.c:1639
 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1026
 tcp_setsockopt+0x136/0x2520 net/ipv4/tcp.c:3696
 __sys_setsockopt+0x2db/0x6a0 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
 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

Memory state around the buggy address:
 ffff88807d37b800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff88807d37b880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff88807d37b900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff88807d37b980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88807d37ba00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc

Fixes: c85bb41e9318 ("igmp: fix ip_mc_sf_allow race [v5]")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Flavio Leitner <fbl@sysclose.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: fix potential xmit stalls caused by TCP_NOTSENT_LOWAT 2022-05-12T10:14:55+00:00 Eric Dumazet edumazet@google.com 2022-04-25T00:34:07+00:00 5d31cc50162176f54ca20f2b8277308e35473da3 [ Upstream commit 4bfe744ff1644fbc0a991a2677dc874475dd6776 ] I had this bug sitting for too long in my pile, it is time to fix it. Thanks to Doug Porter for reminding me of it! We had various attempts in the past, including commit 0cbe6a8f089e ("tcp: remove SOCK_QUEUE_SHRUNK"), but the issue is that TCP stack currently only generates EPOLLOUT from input path, when tp->snd_una has advanced and skb(s) cleaned from rtx queue. If a flow has a big RTT, and/or receives SACKs, it is possible that the notsent part (tp->write_seq - tp->snd_nxt) reaches 0 and no more data can be sent until tp->snd_una finally advances. What is needed is to also check if POLLOUT needs to be generated whenever tp->snd_nxt is advanced, from output path. This bug triggers more often after an idle period, as we do not receive ACK for at least one RTT. tcp_notsent_lowat could be a fraction of what CWND and pacing rate would allow to send during this RTT. In a followup patch, I will remove the bogus call to tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED) from tcp_check_space(). Fact that we have decided to generate an EPOLLOUT does not mean the application has immediately refilled the transmit queue. This optimistic call might have been the reason the bug seemed not too serious. Tested: 200 ms rtt, 1% packet loss, 32 MB tcp_rmem[2] and tcp_wmem[2] $ echo 500000 >/proc/sys/net/ipv4/tcp_notsent_lowat $ cat bench_rr.sh SUM=0 for i in {1..10} do V=`netperf -H remote_host -l30 -t TCP_RR -- -r 10000000,10000 -o LOCAL_BYTES_SENT | egrep -v "MIGRATED|Bytes"` echo $V SUM=$(($SUM + $V)) done echo SUM=$SUM Before patch: $ bench_rr.sh 130000000 80000000 140000000 140000000 140000000 140000000 130000000 40000000 90000000 110000000 SUM=1140000000 After patch: $ bench_rr.sh 430000000 590000000 530000000 450000000 450000000 350000000 450000000 490000000 480000000 460000000 SUM=4680000000 # This is 410 % of the value before patch. Fixes: c9bee3b7fdec ("tcp: TCP_NOTSENT_LOWAT socket option") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Doug Porter <dsp@fb.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4bfe744ff1644fbc0a991a2677dc874475dd6776 ]

I had this bug sitting for too long in my pile, it is time to fix it.

Thanks to Doug Porter for reminding me of it!

We had various attempts in the past, including commit
0cbe6a8f089e ("tcp: remove SOCK_QUEUE_SHRUNK"),
but the issue is that TCP stack currently only generates
EPOLLOUT from input path, when tp->snd_una has advanced
and skb(s) cleaned from rtx queue.

If a flow has a big RTT, and/or receives SACKs, it is possible
that the notsent part (tp->write_seq - tp->snd_nxt) reaches 0
and no more data can be sent until tp->snd_una finally advances.

What is needed is to also check if POLLOUT needs to be generated
whenever tp->snd_nxt is advanced, from output path.

This bug triggers more often after an idle period, as
we do not receive ACK for at least one RTT. tcp_notsent_lowat
could be a fraction of what CWND and pacing rate would allow to
send during this RTT.

In a followup patch, I will remove the bogus call
to tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED)
from tcp_check_space(). Fact that we have decided to generate
an EPOLLOUT does not mean the application has immediately
refilled the transmit queue. This optimistic call
might have been the reason the bug seemed not too serious.

Tested:

200 ms rtt, 1% packet loss, 32 MB tcp_rmem[2] and tcp_wmem[2]

$ echo 500000 >/proc/sys/net/ipv4/tcp_notsent_lowat
$ cat bench_rr.sh
SUM=0
for i in {1..10}
do
 V=`netperf -H remote_host -l30 -t TCP_RR -- -r 10000000,10000 -o LOCAL_BYTES_SENT | egrep -v "MIGRATED|Bytes"`
 echo $V
 SUM=$(($SUM + $V))
done
echo SUM=$SUM

Before patch:
$ bench_rr.sh
130000000
80000000
140000000
140000000
140000000
140000000
130000000
40000000
90000000
110000000
SUM=1140000000

After patch:
$ bench_rr.sh
430000000
590000000
530000000
450000000
450000000
350000000
450000000
490000000
480000000
460000000
SUM=4680000000  # This is 410 % of the value before patch.

Fixes: c9bee3b7fdec ("tcp: TCP_NOTSENT_LOWAT socket option")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Doug Porter <dsp@fb.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ip_gre: Make o_seqno start from 0 in native mode 2022-05-12T10:14:55+00:00 Peilin Ye peilin.ye@bytedance.com 2022-04-21T22:07:57+00:00 1bdd46a8dce18ecdeead95af4f379dc9efa256b7 [ Upstream commit ff827beb706ed719c766acf36449801ded0c17fc ] For GRE and GRETAP devices, currently o_seqno starts from 1 in native mode. According to RFC 2890 2.2., "The first datagram is sent with a sequence number of 0." Fix it. It is worth mentioning that o_seqno already starts from 0 in collect_md mode, see gre_fb_xmit(), where tunnel->o_seqno is passed to gre_build_header() before getting incremented. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit ff827beb706ed719c766acf36449801ded0c17fc ]

For GRE and GRETAP devices, currently o_seqno starts from 1 in native
mode.  According to RFC 2890 2.2., "The first datagram is sent with a
sequence number of 0."  Fix it.

It is worth mentioning that o_seqno already starts from 0 in collect_md
mode, see gre_fb_xmit(), where tunnel->o_seqno is passed to
gre_build_header() before getting incremented.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tcp: make tcp_read_sock() more robust 2022-03-23T08:00:33+00:00 Eric Dumazet edumazet@google.com 2022-03-02T16:17:23+00:00 a09abc44c7de39f54e4bafa2c90aa4455eead8e5 [ Upstream commit e3d5ea2c011ecb16fb94c56a659364e6b30fac94 ] If recv_actor() returns an incorrect value, tcp_read_sock() might loop forever. Instead, issue a one time warning and make sure to make progress. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20220302161723.3910001-2-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e3d5ea2c011ecb16fb94c56a659364e6b30fac94 ]

If recv_actor() returns an incorrect value, tcp_read_sock()
might loop forever.

Instead, issue a one time warning and make sure to make progress.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20220302161723.3910001-2-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
gso: do not skip outer ip header in case of ipip and net_failover 2022-03-02T10:32:02+00:00 Tao Liu thomas.liu@ucloud.cn 2022-02-18T14:35:24+00:00 45d006c2c7ed7baf1fa258fa7b5bc9923d3a983e commit cc20cced0598d9a5ff91ae4ab147b3b5e99ee819 upstream. We encounter a tcp drop issue in our cloud environment. Packet GROed in host forwards to a VM virtio_net nic with net_failover enabled. VM acts as a IPVS LB with ipip encapsulation. The full path like: host gro -> vm virtio_net rx -> net_failover rx -> ipvs fullnat -> ipip encap -> net_failover tx -> virtio_net tx When net_failover transmits a ipip pkt (gso_type = 0x0103, which means SKB_GSO_TCPV4, SKB_GSO_DODGY and SKB_GSO_IPXIP4), there is no gso did because it supports TSO and GSO_IPXIP4. But network_header points to inner ip header. Call Trace: tcp4_gso_segment ------> return NULL inet_gso_segment ------> inner iph, network_header points to ipip_gso_segment inet_gso_segment ------> outer iph skb_mac_gso_segment Afterwards virtio_net transmits the pkt, only inner ip header is modified. And the outer one just keeps unchanged. The pkt will be dropped in remote host. Call Trace: inet_gso_segment ------> inner iph, outer iph is skipped skb_mac_gso_segment __skb_gso_segment validate_xmit_skb validate_xmit_skb_list sch_direct_xmit __qdisc_run __dev_queue_xmit ------> virtio_net dev_hard_start_xmit __dev_queue_xmit ------> net_failover ip_finish_output2 ip_output iptunnel_xmit ip_tunnel_xmit ipip_tunnel_xmit ------> ipip dev_hard_start_xmit __dev_queue_xmit ip_finish_output2 ip_output ip_forward ip_rcv __netif_receive_skb_one_core netif_receive_skb_internal napi_gro_receive receive_buf virtnet_poll net_rx_action The root cause of this issue is specific with the rare combination of SKB_GSO_DODGY and a tunnel device that adds an SKB_GSO_ tunnel option. SKB_GSO_DODGY is set from external virtio_net. We need to reset network header when callbacks.gso_segment() returns NULL. This patch also includes ipv6_gso_segment(), considering SIT, etc. Fixes: cb32f511a70b ("ipip: add GSO/TSO support") Signed-off-by: Tao Liu <thomas.liu@ucloud.cn> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit cc20cced0598d9a5ff91ae4ab147b3b5e99ee819 upstream.

We encounter a tcp drop issue in our cloud environment. Packet GROed in
host forwards to a VM virtio_net nic with net_failover enabled. VM acts
as a IPVS LB with ipip encapsulation. The full path like:
host gro -> vm virtio_net rx -> net_failover rx -> ipvs fullnat
 -> ipip encap -> net_failover tx -> virtio_net tx

When net_failover transmits a ipip pkt (gso_type = 0x0103, which means
SKB_GSO_TCPV4, SKB_GSO_DODGY and SKB_GSO_IPXIP4), there is no gso
did because it supports TSO and GSO_IPXIP4. But network_header points to
inner ip header.

Call Trace:
 tcp4_gso_segment        ------> return NULL
 inet_gso_segment        ------> inner iph, network_header points to
 ipip_gso_segment
 inet_gso_segment        ------> outer iph
 skb_mac_gso_segment

Afterwards virtio_net transmits the pkt, only inner ip header is modified.
And the outer one just keeps unchanged. The pkt will be dropped in remote
host.

Call Trace:
 inet_gso_segment        ------> inner iph, outer iph is skipped
 skb_mac_gso_segment
 __skb_gso_segment
 validate_xmit_skb
 validate_xmit_skb_list
 sch_direct_xmit
 __qdisc_run
 __dev_queue_xmit        ------> virtio_net
 dev_hard_start_xmit
 __dev_queue_xmit        ------> net_failover
 ip_finish_output2
 ip_output
 iptunnel_xmit
 ip_tunnel_xmit
 ipip_tunnel_xmit        ------> ipip
 dev_hard_start_xmit
 __dev_queue_xmit
 ip_finish_output2
 ip_output
 ip_forward
 ip_rcv
 __netif_receive_skb_one_core
 netif_receive_skb_internal
 napi_gro_receive
 receive_buf
 virtnet_poll
 net_rx_action

The root cause of this issue is specific with the rare combination of
SKB_GSO_DODGY and a tunnel device that adds an SKB_GSO_ tunnel option.
SKB_GSO_DODGY is set from external virtio_net. We need to reset network
header when callbacks.gso_segment() returns NULL.

This patch also includes ipv6_gso_segment(), considering SIT, etc.

Fixes: cb32f511a70b ("ipip: add GSO/TSO support")
Signed-off-by: Tao Liu <thomas.liu@ucloud.cn>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xfrm: Don't accidentally set RTO_ONLINK in decode_session4() 2022-02-23T10:56:40+00:00 Guillaume Nault gnault@redhat.com 2022-01-10T13:43:06+00:00 5bb337134df729efdda987d543525239f2f6baf8 commit 23e7b1bfed61e301853b5e35472820d919498278 upstream. Similar to commit 94e2238969e8 ("xfrm4: strip ECN bits from tos field"), clear the ECN bits from iph->tos when setting ->flowi4_tos. This ensures that the last bit of ->flowi4_tos is cleared, so ip_route_output_key_hash() isn't going to restrict the scope of the route lookup. Use ~INET_ECN_MASK instead of IPTOS_RT_MASK, because we have no reason to clear the high order bits. Found by code inspection, compile tested only. Fixes: 4da3089f2b58 ("[IPSEC]: Use TOS when doing tunnel lookups") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> [sudip: manually backport to previous location] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 23e7b1bfed61e301853b5e35472820d919498278 upstream.

Similar to commit 94e2238969e8 ("xfrm4: strip ECN bits from tos field"),
clear the ECN bits from iph->tos when setting ->flowi4_tos.
This ensures that the last bit of ->flowi4_tos is cleared, so
ip_route_output_key_hash() isn't going to restrict the scope of the
route lookup.

Use ~INET_ECN_MASK instead of IPTOS_RT_MASK, because we have no reason
to clear the high order bits.

Found by code inspection, compile tested only.

Fixes: 4da3089f2b58 ("[IPSEC]: Use TOS when doing tunnel lookups")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[sudip: manually backport to previous location]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipmr,ip6mr: acquire RTNL before calling ip[6]mr_free_table() on failure path 2022-02-16T11:43:53+00:00 Eric Dumazet edumazet@google.com 2022-02-08T05:34:51+00:00 80c529322600dfb1f985b5e3f14c3c6f522ce154 [ Upstream commit 5611a00697c8ecc5aad04392bea629e9d6a20463 ] ip[6]mr_free_table() can only be called under RTNL lock. RTNL: assertion failed at net/core/dev.c (10367) WARNING: CPU: 1 PID: 5890 at net/core/dev.c:10367 unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367 Modules linked in: CPU: 1 PID: 5890 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller-11627-g422ee58dc0ef #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367 Code: 0f 85 9b ee ff ff e8 69 07 4b fa ba 7f 28 00 00 48 c7 c6 00 90 ae 8a 48 c7 c7 40 90 ae 8a c6 05 6d b1 51 06 01 e8 8c 90 d8 01 <0f> 0b e9 70 ee ff ff e8 3e 07 4b fa 4c 89 e7 e8 86 2a 59 fa e9 ee RSP: 0018:ffffc900046ff6e0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888050f51d00 RSI: ffffffff815fa008 RDI: fffff520008dfece RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815f3d6e R11: 0000000000000000 R12: 00000000fffffff4 R13: dffffc0000000000 R14: ffffc900046ff750 R15: ffff88807b7dc000 FS: 00007f4ab736e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee0b4f8990 CR3: 000000001e7d2000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> mroute_clean_tables+0x244/0xb40 net/ipv6/ip6mr.c:1509 ip6mr_free_table net/ipv6/ip6mr.c:389 [inline] ip6mr_rules_init net/ipv6/ip6mr.c:246 [inline] ip6mr_net_init net/ipv6/ip6mr.c:1306 [inline] ip6mr_net_init+0x3f0/0x4e0 net/ipv6/ip6mr.c:1298 ops_init+0xaf/0x470 net/core/net_namespace.c:140 setup_net+0x54f/0xbb0 net/core/net_namespace.c:331 copy_net_ns+0x318/0x760 net/core/net_namespace.c:475 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2e0c/0x7300 kernel/fork.c:2167 kernel_clone+0xe7/0xab0 kernel/fork.c:2555 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672 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 RIP: 0033:0x7f4ab89f9059 Code: Unable to access opcode bytes at RIP 0x7f4ab89f902f. RSP: 002b:00007f4ab736e118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4ab8b0bf60 RCX: 00007f4ab89f9059 RDX: 0000000020000280 RSI: 0000000020000270 RDI: 0000000040200000 RBP: 00007f4ab8a5308d R08: 0000000020000300 R09: 0000000020000300 R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffc3977cc1f R14: 00007f4ab736e300 R15: 0000000000022000 </TASK> Fixes: f243e5a7859a ("ipmr,ip6mr: call ip6mr_free_table() on failure path") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cong Wang <cong.wang@bytedance.com> Reported-by: syzbot <syzkaller@googlegroups.com> Link: https://lore.kernel.org/r/20220208053451.2885398-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 5611a00697c8ecc5aad04392bea629e9d6a20463 ]

ip[6]mr_free_table() can only be called under RTNL lock.

RTNL: assertion failed at net/core/dev.c (10367)
WARNING: CPU: 1 PID: 5890 at net/core/dev.c:10367 unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Modules linked in:
CPU: 1 PID: 5890 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller-11627-g422ee58dc0ef #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Code: 0f 85 9b ee ff ff e8 69 07 4b fa ba 7f 28 00 00 48 c7 c6 00 90 ae 8a 48 c7 c7 40 90 ae 8a c6 05 6d b1 51 06 01 e8 8c 90 d8 01 <0f> 0b e9 70 ee ff ff e8 3e 07 4b fa 4c 89 e7 e8 86 2a 59 fa e9 ee
RSP: 0018:ffffc900046ff6e0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888050f51d00 RSI: ffffffff815fa008 RDI: fffff520008dfece
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815f3d6e R11: 0000000000000000 R12: 00000000fffffff4
R13: dffffc0000000000 R14: ffffc900046ff750 R15: ffff88807b7dc000
FS:  00007f4ab736e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee0b4f8990 CR3: 000000001e7d2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mroute_clean_tables+0x244/0xb40 net/ipv6/ip6mr.c:1509
 ip6mr_free_table net/ipv6/ip6mr.c:389 [inline]
 ip6mr_rules_init net/ipv6/ip6mr.c:246 [inline]
 ip6mr_net_init net/ipv6/ip6mr.c:1306 [inline]
 ip6mr_net_init+0x3f0/0x4e0 net/ipv6/ip6mr.c:1298
 ops_init+0xaf/0x470 net/core/net_namespace.c:140
 setup_net+0x54f/0xbb0 net/core/net_namespace.c:331
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:475
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178
 copy_process+0x2e0c/0x7300 kernel/fork.c:2167
 kernel_clone+0xe7/0xab0 kernel/fork.c:2555
 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672
 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
RIP: 0033:0x7f4ab89f9059
Code: Unable to access opcode bytes at RIP 0x7f4ab89f902f.
RSP: 002b:00007f4ab736e118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f4ab8b0bf60 RCX: 00007f4ab89f9059
RDX: 0000000020000280 RSI: 0000000020000270 RDI: 0000000040200000
RBP: 00007f4ab8a5308d R08: 0000000020000300 R09: 0000000020000300
R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc3977cc1f R14: 00007f4ab736e300 R15: 0000000000022000
 </TASK>

Fixes: f243e5a7859a ("ipmr,ip6mr: call ip6mr_free_table() on failure path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <cong.wang@bytedance.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220208053451.2885398-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv4: tcp: send zero IPID in SYNACK messages 2022-02-08T17:15:28+00:00 Eric Dumazet edumazet@google.com 2022-01-27T01:10:21+00:00 ff3617bc0622f2914a8334cb35227290239325d1 [ Upstream commit 970a5a3ea86da637471d3cd04d513a0755aba4bf ] In commit 431280eebed9 ("ipv4: tcp: send zero IPID for RST and ACK sent in SYN-RECV and TIME-WAIT state") we took care of some ctl packets sent by TCP. It turns out we need to use a similar strategy for SYNACK packets. By default, they carry IP_DF and IPID==0, but there are ways to ask them to use the hashed IP ident generator and thus be used to build off-path attacks. (Ref: Off-Path TCP Exploits of the Mixed IPID Assignment) One of this way is to force (before listener is started) echo 1 >/proc/sys/net/ipv4/ip_no_pmtu_disc Another way is using forged ICMP ICMP_FRAG_NEEDED with a very small MTU (like 68) to force a false return from ip_dont_fragment() In this patch, ip_build_and_send_pkt() uses the following heuristics. 1) Most SYNACK packets are smaller than IPV4_MIN_MTU and therefore can use IP_DF regardless of the listener or route pmtu setting. 2) In case the SYNACK packet is bigger than IPV4_MIN_MTU, we use prandom_u32() generator instead of the IPv4 hashed ident one. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Ray Che <xijiache@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Cc: Geoff Alexander <alexandg@cs.unm.edu> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 970a5a3ea86da637471d3cd04d513a0755aba4bf ]

In commit 431280eebed9 ("ipv4: tcp: send zero IPID for RST and
ACK sent in SYN-RECV and TIME-WAIT state") we took care of some
ctl packets sent by TCP.

It turns out we need to use a similar strategy for SYNACK packets.

By default, they carry IP_DF and IPID==0, but there are ways
to ask them to use the hashed IP ident generator and thus
be used to build off-path attacks.
(Ref: Off-Path TCP Exploits of the Mixed IPID Assignment)

One of this way is to force (before listener is started)
echo 1 >/proc/sys/net/ipv4/ip_no_pmtu_disc

Another way is using forged ICMP ICMP_FRAG_NEEDED
with a very small MTU (like 68) to force a false return from
ip_dont_fragment()

In this patch, ip_build_and_send_pkt() uses the following
heuristics.

1) Most SYNACK packets are smaller than IPV4_MIN_MTU and therefore
can use IP_DF regardless of the listener or route pmtu setting.

2) In case the SYNACK packet is bigger than IPV4_MIN_MTU,
we use prandom_u32() generator instead of the IPv4 hashed ident one.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Ray Che <xijiache@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Cc: Geoff Alexander <alexandg@cs.unm.edu>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv4: raw: lock the socket in raw_bind() 2022-02-08T17:15:28+00:00 Eric Dumazet edumazet@google.com 2022-01-27T00:51:16+00:00 daac3482a5b526f93dafe61da2ae061afe3e1f89 [ Upstream commit 153a0d187e767c68733b8e9f46218eb1f41ab902 ] For some reason, raw_bind() forgot to lock the socket. BUG: KCSAN: data-race in __ip4_datagram_connect / raw_bind write to 0xffff8881170d4308 of 4 bytes by task 5466 on cpu 0: raw_bind+0x1b0/0x250 net/ipv4/raw.c:739 inet_bind+0x56/0xa0 net/ipv4/af_inet.c:443 __sys_bind+0x14b/0x1b0 net/socket.c:1697 __do_sys_bind net/socket.c:1708 [inline] __se_sys_bind net/socket.c:1706 [inline] __x64_sys_bind+0x3d/0x50 net/socket.c:1706 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881170d4308 of 4 bytes by task 5468 on cpu 1: __ip4_datagram_connect+0xb7/0x7b0 net/ipv4/datagram.c:39 ip4_datagram_connect+0x2a/0x40 net/ipv4/datagram.c:89 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576 __sys_connect_file net/socket.c:1900 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1917 __do_sys_connect net/socket.c:1927 [inline] __se_sys_connect net/socket.c:1924 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:1924 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000000 -> 0x0003007f Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 5468 Comm: syz-executor.5 Not tainted 5.17.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 153a0d187e767c68733b8e9f46218eb1f41ab902 ]

For some reason, raw_bind() forgot to lock the socket.

BUG: KCSAN: data-race in __ip4_datagram_connect / raw_bind

write to 0xffff8881170d4308 of 4 bytes by task 5466 on cpu 0:
 raw_bind+0x1b0/0x250 net/ipv4/raw.c:739
 inet_bind+0x56/0xa0 net/ipv4/af_inet.c:443
 __sys_bind+0x14b/0x1b0 net/socket.c:1697
 __do_sys_bind net/socket.c:1708 [inline]
 __se_sys_bind net/socket.c:1706 [inline]
 __x64_sys_bind+0x3d/0x50 net/socket.c:1706
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881170d4308 of 4 bytes by task 5468 on cpu 1:
 __ip4_datagram_connect+0xb7/0x7b0 net/ipv4/datagram.c:39
 ip4_datagram_connect+0x2a/0x40 net/ipv4/datagram.c:89
 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576
 __sys_connect_file net/socket.c:1900 [inline]
 __sys_connect+0x197/0x1b0 net/socket.c:1917
 __do_sys_connect net/socket.c:1927 [inline]
 __se_sys_connect net/socket.c:1924 [inline]
 __x64_sys_connect+0x3d/0x50 net/socket.c:1924
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000 -> 0x0003007f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5468 Comm: syz-executor.5 Not tainted 5.17.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cipso,calipso: resolve a number of problems with the DOI refcounts 2022-01-27T07:47:42+00:00 Paul Moore paul@paul-moore.com 2022-01-24T16:32:21+00:00 f49f0e65a95664b648e058aa923f651ec08dfeb7 commit ad5d07f4a9cd671233ae20983848874731102c08 upstream. The current CIPSO and CALIPSO refcounting scheme for the DOI definitions is a bit flawed in that we: 1. Don't correctly match gets/puts in netlbl_cipsov4_list(). 2. Decrement the refcount on each attempt to remove the DOI from the DOI list, only removing it from the list once the refcount drops to zero. This patch fixes these problems by adding the missing "puts" to netlbl_cipsov4_list() and introduces a more conventional, i.e. not-buggy, refcounting mechanism to the DOI definitions. Upon the addition of a DOI to the DOI list, it is initialized with a refcount of one, removing a DOI from the list removes it from the list and drops the refcount by one; "gets" and "puts" behave as expected with respect to refcounts, increasing and decreasing the DOI's refcount by one. Fixes: b1edeb102397 ("netlabel: Replace protocol/NetLabel linking with refrerence counts") Fixes: d7cce01504a0 ("netlabel: Add support for removing a CALIPSO DOI.") Reported-by: syzbot+9ec037722d2603a9f52e@syzkaller.appspotmail.com Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ad5d07f4a9cd671233ae20983848874731102c08 upstream.

The current CIPSO and CALIPSO refcounting scheme for the DOI
definitions is a bit flawed in that we:

1. Don't correctly match gets/puts in netlbl_cipsov4_list().
2. Decrement the refcount on each attempt to remove the DOI from the
   DOI list, only removing it from the list once the refcount drops
   to zero.

This patch fixes these problems by adding the missing "puts" to
netlbl_cipsov4_list() and introduces a more conventional, i.e.
not-buggy, refcounting mechanism to the DOI definitions.  Upon the
addition of a DOI to the DOI list, it is initialized with a refcount
of one, removing a DOI from the list removes it from the list and
drops the refcount by one; "gets" and "puts" behave as expected with
respect to refcounts, increasing and decreasing the DOI's refcount by
one.

Fixes: b1edeb102397 ("netlabel: Replace protocol/NetLabel linking with refrerence counts")
Fixes: d7cce01504a0 ("netlabel: Add support for removing a CALIPSO DOI.")
Reported-by: syzbot+9ec037722d2603a9f52e@syzkaller.appspotmail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>