linux-stable.git/net/llc, branch v6.8 Linux kernel stable tree llc: call sock_orphan() at release time 2024-01-30T12:49:09+00:00 Eric Dumazet edumazet@google.com 2024-01-26T16:55:32+00:00 aa2b2eb3934859904c287bf5434647ba72e14c1c syzbot reported an interesting trace [1] caused by a stale sk->sk_wq pointer in a closed llc socket. In commit ff7b11aa481f ("net: socket: set sock->sk to NULL after calling proto_ops::release()") Eric Biggers hinted that some protocols are missing a sock_orphan(), we need to perform a full audit. In net-next, I plan to clear sock->sk from sock_orphan() and amend Eric patch to add a warning. [1] BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline] BUG: KASAN: slab-use-after-free in waitqueue_active include/linux/wait.h:127 [inline] BUG: KASAN: slab-use-after-free in sock_def_write_space_wfree net/core/sock.c:3384 [inline] BUG: KASAN: slab-use-after-free in sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468 Read of size 8 at addr ffff88802f4fc880 by task ksoftirqd/1/27 CPU: 1 PID: 27 Comm: ksoftirqd/1 Not tainted 6.8.0-rc1-syzkaller-00049-g6098d87eaf31 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc4/0x620 mm/kasan/report.c:488 kasan_report+0xda/0x110 mm/kasan/report.c:601 list_empty include/linux/list.h:373 [inline] waitqueue_active include/linux/wait.h:127 [inline] sock_def_write_space_wfree net/core/sock.c:3384 [inline] sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468 skb_release_head_state+0xa3/0x2b0 net/core/skbuff.c:1080 skb_release_all net/core/skbuff.c:1092 [inline] napi_consume_skb+0x119/0x2b0 net/core/skbuff.c:1404 e1000_unmap_and_free_tx_resource+0x144/0x200 drivers/net/ethernet/intel/e1000/e1000_main.c:1970 e1000_clean_tx_irq drivers/net/ethernet/intel/e1000/e1000_main.c:3860 [inline] e1000_clean+0x4a1/0x26e0 drivers/net/ethernet/intel/e1000/e1000_main.c:3801 __napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6576 napi_poll net/core/dev.c:6645 [inline] net_rx_action+0x956/0xe90 net/core/dev.c:6778 __do_softirq+0x21a/0x8de kernel/softirq.c:553 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x660/0xa10 kernel/smpboot.c:164 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 </TASK> Allocated by task 5167: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:314 [inline] __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_lru+0x142/0x6f0 mm/slub.c:3879 alloc_inode_sb include/linux/fs.h:3019 [inline] sock_alloc_inode+0x25/0x1c0 net/socket.c:308 alloc_inode+0x5d/0x220 fs/inode.c:260 new_inode_pseudo+0x16/0x80 fs/inode.c:1005 sock_alloc+0x40/0x270 net/socket.c:634 __sock_create+0xbc/0x800 net/socket.c:1535 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x14c/0x260 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 0: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640 poison_slab_object mm/kasan/common.c:241 [inline] __kasan_slab_free+0x121/0x1b0 mm/kasan/common.c:257 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kmem_cache_free+0x129/0x350 mm/slub.c:4363 i_callback+0x43/0x70 fs/inode.c:249 rcu_do_batch kernel/rcu/tree.c:2158 [inline] rcu_core+0x819/0x1680 kernel/rcu/tree.c:2433 __do_softirq+0x21a/0x8de kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:586 __call_rcu_common.constprop.0+0x9a/0x7b0 kernel/rcu/tree.c:2683 destroy_inode+0x129/0x1b0 fs/inode.c:315 iput_final fs/inode.c:1739 [inline] iput.part.0+0x560/0x7b0 fs/inode.c:1765 iput+0x5c/0x80 fs/inode.c:1755 dentry_unlink_inode+0x292/0x430 fs/dcache.c:400 __dentry_kill+0x1ca/0x5f0 fs/dcache.c:603 dput.part.0+0x4ac/0x9a0 fs/dcache.c:845 dput+0x1f/0x30 fs/dcache.c:835 __fput+0x3b9/0xb70 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa8a/0x2ad0 kernel/exit.c:871 do_group_exit+0xd4/0x2a0 kernel/exit.c:1020 __do_sys_exit_group kernel/exit.c:1031 [inline] __se_sys_exit_group kernel/exit.c:1029 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88802f4fc800 which belongs to the cache sock_inode_cache of size 1408 The buggy address is located 128 bytes inside of freed 1408-byte region [ffff88802f4fc800, ffff88802f4fcd80) The buggy address belongs to the physical page: page:ffffea0000bd3e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f4f8 head:ffffea0000bd3e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888013b06b40 0000000000000000 0000000000000001 raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 4956, tgid 4956 (sshd), ts 31423924727, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311 __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2190 [inline] allocate_slab mm/slub.c:2354 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2407 ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625 __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc_lru+0x379/0x6f0 mm/slub.c:3879 alloc_inode_sb include/linux/fs.h:3019 [inline] sock_alloc_inode+0x25/0x1c0 net/socket.c:308 alloc_inode+0x5d/0x220 fs/inode.c:260 new_inode_pseudo+0x16/0x80 fs/inode.c:1005 sock_alloc+0x40/0x270 net/socket.c:634 __sock_create+0xbc/0x800 net/socket.c:1535 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x14c/0x260 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b page_owner free stack trace missing Memory state around the buggy address: ffff88802f4fc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802f4fc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802f4fc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802f4fc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802f4fc980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 43815482370c ("net: sock_def_readable() and friends RCU conversion") Reported-and-tested-by: syzbot+32b89eaa102b372ff76d@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240126165532.3396702-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
syzbot reported an interesting trace [1] caused by a stale sk->sk_wq
pointer in a closed llc socket.

In commit ff7b11aa481f ("net: socket: set sock->sk to NULL after
calling proto_ops::release()") Eric Biggers hinted that some protocols
are missing a sock_orphan(), we need to perform a full audit.

In net-next, I plan to clear sock->sk from sock_orphan() and
amend Eric patch to add a warning.

[1]
 BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline]
 BUG: KASAN: slab-use-after-free in waitqueue_active include/linux/wait.h:127 [inline]
 BUG: KASAN: slab-use-after-free in sock_def_write_space_wfree net/core/sock.c:3384 [inline]
 BUG: KASAN: slab-use-after-free in sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468
Read of size 8 at addr ffff88802f4fc880 by task ksoftirqd/1/27

CPU: 1 PID: 27 Comm: ksoftirqd/1 Not tainted 6.8.0-rc1-syzkaller-00049-g6098d87eaf31 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0xc4/0x620 mm/kasan/report.c:488
  kasan_report+0xda/0x110 mm/kasan/report.c:601
  list_empty include/linux/list.h:373 [inline]
  waitqueue_active include/linux/wait.h:127 [inline]
  sock_def_write_space_wfree net/core/sock.c:3384 [inline]
  sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468
  skb_release_head_state+0xa3/0x2b0 net/core/skbuff.c:1080
  skb_release_all net/core/skbuff.c:1092 [inline]
  napi_consume_skb+0x119/0x2b0 net/core/skbuff.c:1404
  e1000_unmap_and_free_tx_resource+0x144/0x200 drivers/net/ethernet/intel/e1000/e1000_main.c:1970
  e1000_clean_tx_irq drivers/net/ethernet/intel/e1000/e1000_main.c:3860 [inline]
  e1000_clean+0x4a1/0x26e0 drivers/net/ethernet/intel/e1000/e1000_main.c:3801
  __napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6576
  napi_poll net/core/dev.c:6645 [inline]
  net_rx_action+0x956/0xe90 net/core/dev.c:6778
  __do_softirq+0x21a/0x8de kernel/softirq.c:553
  run_ksoftirqd kernel/softirq.c:921 [inline]
  run_ksoftirqd+0x31/0x60 kernel/softirq.c:913
  smpboot_thread_fn+0x660/0xa10 kernel/smpboot.c:164
  kthread+0x2c6/0x3a0 kernel/kthread.c:388
  ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>

Allocated by task 5167:
  kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
  unpoison_slab_object mm/kasan/common.c:314 [inline]
  __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:340
  kasan_slab_alloc include/linux/kasan.h:201 [inline]
  slab_post_alloc_hook mm/slub.c:3813 [inline]
  slab_alloc_node mm/slub.c:3860 [inline]
  kmem_cache_alloc_lru+0x142/0x6f0 mm/slub.c:3879
  alloc_inode_sb include/linux/fs.h:3019 [inline]
  sock_alloc_inode+0x25/0x1c0 net/socket.c:308
  alloc_inode+0x5d/0x220 fs/inode.c:260
  new_inode_pseudo+0x16/0x80 fs/inode.c:1005
  sock_alloc+0x40/0x270 net/socket.c:634
  __sock_create+0xbc/0x800 net/socket.c:1535
  sock_create net/socket.c:1622 [inline]
  __sys_socket_create net/socket.c:1659 [inline]
  __sys_socket+0x14c/0x260 net/socket.c:1706
  __do_sys_socket net/socket.c:1720 [inline]
  __se_sys_socket net/socket.c:1718 [inline]
  __x64_sys_socket+0x72/0xb0 net/socket.c:1718
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Freed by task 0:
  kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
  kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
  poison_slab_object mm/kasan/common.c:241 [inline]
  __kasan_slab_free+0x121/0x1b0 mm/kasan/common.c:257
  kasan_slab_free include/linux/kasan.h:184 [inline]
  slab_free_hook mm/slub.c:2121 [inline]
  slab_free mm/slub.c:4299 [inline]
  kmem_cache_free+0x129/0x350 mm/slub.c:4363
  i_callback+0x43/0x70 fs/inode.c:249
  rcu_do_batch kernel/rcu/tree.c:2158 [inline]
  rcu_core+0x819/0x1680 kernel/rcu/tree.c:2433
  __do_softirq+0x21a/0x8de kernel/softirq.c:553

Last potentially related work creation:
  kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
  __kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:586
  __call_rcu_common.constprop.0+0x9a/0x7b0 kernel/rcu/tree.c:2683
  destroy_inode+0x129/0x1b0 fs/inode.c:315
  iput_final fs/inode.c:1739 [inline]
  iput.part.0+0x560/0x7b0 fs/inode.c:1765
  iput+0x5c/0x80 fs/inode.c:1755
  dentry_unlink_inode+0x292/0x430 fs/dcache.c:400
  __dentry_kill+0x1ca/0x5f0 fs/dcache.c:603
  dput.part.0+0x4ac/0x9a0 fs/dcache.c:845
  dput+0x1f/0x30 fs/dcache.c:835
  __fput+0x3b9/0xb70 fs/file_table.c:384
  task_work_run+0x14d/0x240 kernel/task_work.c:180
  exit_task_work include/linux/task_work.h:38 [inline]
  do_exit+0xa8a/0x2ad0 kernel/exit.c:871
  do_group_exit+0xd4/0x2a0 kernel/exit.c:1020
  __do_sys_exit_group kernel/exit.c:1031 [inline]
  __se_sys_exit_group kernel/exit.c:1029 [inline]
  __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88802f4fc800
 which belongs to the cache sock_inode_cache of size 1408
The buggy address is located 128 bytes inside of
 freed 1408-byte region [ffff88802f4fc800, ffff88802f4fcd80)

The buggy address belongs to the physical page:
page:ffffea0000bd3e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f4f8
head:ffffea0000bd3e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888013b06b40 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 4956, tgid 4956 (sshd), ts 31423924727, free_ts 0
  set_page_owner include/linux/page_owner.h:31 [inline]
  post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533
  prep_new_page mm/page_alloc.c:1540 [inline]
  get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
  __alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567
  __alloc_pages_node include/linux/gfp.h:238 [inline]
  alloc_pages_node include/linux/gfp.h:261 [inline]
  alloc_slab_page mm/slub.c:2190 [inline]
  allocate_slab mm/slub.c:2354 [inline]
  new_slab+0xcc/0x3a0 mm/slub.c:2407
  ___slab_alloc+0x4af/0x19a0 mm/slub.c:3540
  __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
  __slab_alloc_node mm/slub.c:3678 [inline]
  slab_alloc_node mm/slub.c:3850 [inline]
  kmem_cache_alloc_lru+0x379/0x6f0 mm/slub.c:3879
  alloc_inode_sb include/linux/fs.h:3019 [inline]
  sock_alloc_inode+0x25/0x1c0 net/socket.c:308
  alloc_inode+0x5d/0x220 fs/inode.c:260
  new_inode_pseudo+0x16/0x80 fs/inode.c:1005
  sock_alloc+0x40/0x270 net/socket.c:634
  __sock_create+0xbc/0x800 net/socket.c:1535
  sock_create net/socket.c:1622 [inline]
  __sys_socket_create net/socket.c:1659 [inline]
  __sys_socket+0x14c/0x260 net/socket.c:1706
  __do_sys_socket net/socket.c:1720 [inline]
  __se_sys_socket net/socket.c:1718 [inline]
  __x64_sys_socket+0x72/0xb0 net/socket.c:1718
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802f4fc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802f4fc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802f4fc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88802f4fc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802f4fc980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 43815482370c ("net: sock_def_readable() and friends RCU conversion")
Reported-and-tested-by: syzbot+32b89eaa102b372ff76d@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240126165532.3396702-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
llc: Drop support for ETH_P_TR_802_2. 2024-01-20T05:30:09+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2024-01-19T01:55:15+00:00 e3f9bed9bee261e3347131764e42aeedf1ffea61 syzbot reported an uninit-value bug below. [0] llc supports ETH_P_802_2 (0x0004) and used to support ETH_P_TR_802_2 (0x0011), and syzbot abused the latter to trigger the bug. write$tun(r0, &(0x7f0000000040)={@val={0x0, 0x11}, @val, @mpls={[], @llc={@snap={0xaa, 0x1, ')', "90e5dd"}}}}, 0x16) llc_conn_handler() initialises local variables {saddr,daddr}.mac based on skb in llc_pdu_decode_sa()/llc_pdu_decode_da() and passes them to __llc_lookup(). However, the initialisation is done only when skb->protocol is htons(ETH_P_802_2), otherwise, __llc_lookup_established() and __llc_lookup_listener() will read garbage. The missing initialisation existed prior to commit 211ed865108e ("net: delete all instances of special processing for token ring"). It removed the part to kick out the token ring stuff but forgot to close the door allowing ETH_P_TR_802_2 packets to sneak into llc_rcv(). Let's remove llc_tr_packet_type and complete the deprecation. [0]: BUG: KMSAN: uninit-value in __llc_lookup_established+0xe9d/0xf90 __llc_lookup_established+0xe9d/0xf90 __llc_lookup net/llc/llc_conn.c:611 [inline] llc_conn_handler+0x4bd/0x1360 net/llc/llc_conn.c:791 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206 __netif_receive_skb_one_core net/core/dev.c:5527 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5641 netif_receive_skb_internal net/core/dev.c:5727 [inline] netif_receive_skb+0x58/0x660 net/core/dev.c:5786 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555 tun_get_user+0x53af/0x66d0 drivers/net/tun.c:2002 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048 call_write_iter include/linux/fs.h:2020 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x8ef/0x1490 fs/read_write.c:584 ksys_write+0x20f/0x4c0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x93/0xd0 fs/read_write.c:646 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Local variable daddr created at: llc_conn_handler+0x53/0x1360 net/llc/llc_conn.c:783 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206 CPU: 1 PID: 5004 Comm: syz-executor994 Not tainted 6.6.0-syzkaller-14500-g1c41041124bd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Fixes: 211ed865108e ("net: delete all instances of special processing for token ring") Reported-by: syzbot+b5ad66046b913bc04c6f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=b5ad66046b913bc04c6f Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240119015515.61898-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
syzbot reported an uninit-value bug below. [0]

llc supports ETH_P_802_2 (0x0004) and used to support ETH_P_TR_802_2
(0x0011), and syzbot abused the latter to trigger the bug.

  write$tun(r0, &(0x7f0000000040)={@val={0x0, 0x11}, @val, @mpls={[], @llc={@snap={0xaa, 0x1, ')', "90e5dd"}}}}, 0x16)

llc_conn_handler() initialises local variables {saddr,daddr}.mac
based on skb in llc_pdu_decode_sa()/llc_pdu_decode_da() and passes
them to __llc_lookup().

However, the initialisation is done only when skb->protocol is
htons(ETH_P_802_2), otherwise, __llc_lookup_established() and
__llc_lookup_listener() will read garbage.

The missing initialisation existed prior to commit 211ed865108e
("net: delete all instances of special processing for token ring").

It removed the part to kick out the token ring stuff but forgot to
close the door allowing ETH_P_TR_802_2 packets to sneak into llc_rcv().

Let's remove llc_tr_packet_type and complete the deprecation.

[0]:
BUG: KMSAN: uninit-value in __llc_lookup_established+0xe9d/0xf90
 __llc_lookup_established+0xe9d/0xf90
 __llc_lookup net/llc/llc_conn.c:611 [inline]
 llc_conn_handler+0x4bd/0x1360 net/llc/llc_conn.c:791
 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206
 __netif_receive_skb_one_core net/core/dev.c:5527 [inline]
 __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5641
 netif_receive_skb_internal net/core/dev.c:5727 [inline]
 netif_receive_skb+0x58/0x660 net/core/dev.c:5786
 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555
 tun_get_user+0x53af/0x66d0 drivers/net/tun.c:2002
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:2020 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x8ef/0x1490 fs/read_write.c:584
 ksys_write+0x20f/0x4c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Local variable daddr created at:
 llc_conn_handler+0x53/0x1360 net/llc/llc_conn.c:783
 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206

CPU: 1 PID: 5004 Comm: syz-executor994 Not tainted 6.6.0-syzkaller-14500-g1c41041124bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023

Fixes: 211ed865108e ("net: delete all instances of special processing for token ring")
Reported-by: syzbot+b5ad66046b913bc04c6f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b5ad66046b913bc04c6f
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240119015515.61898-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
llc: make llc_ui_sendmsg() more robust against bonding changes 2024-01-20T05:28:50+00:00 Eric Dumazet edumazet@google.com 2024-01-18T18:36:25+00:00 dad555c816a50c6a6a8a86be1f9177673918c647 syzbot was able to trick llc_ui_sendmsg(), allocating an skb with no headroom, but subsequently trying to push 14 bytes of Ethernet header [1] Like some others, llc_ui_sendmsg() releases the socket lock before calling sock_alloc_send_skb(). Then it acquires it again, but does not redo all the sanity checks that were performed. This fix: - Uses LL_RESERVED_SPACE() to reserve space. - Check all conditions again after socket lock is held again. - Do not account Ethernet header for mtu limitation. [1] skbuff: skb_under_panic: text:ffff800088baa334 len:1514 put:14 head:ffff0000c9c37000 data:ffff0000c9c36ff2 tail:0x5dc end:0x6c0 dev:bond0 kernel BUG at net/core/skbuff.c:193 ! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 6875 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00101-g0802e17d9aca-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : skb_panic net/core/skbuff.c:189 [inline] pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203 lr : skb_panic net/core/skbuff.c:189 [inline] lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203 sp : ffff800096f97000 x29: ffff800096f97010 x28: ffff80008cc8d668 x27: dfff800000000000 x26: ffff0000cb970c90 x25: 00000000000005dc x24: ffff0000c9c36ff2 x23: ffff0000c9c37000 x22: 00000000000005ea x21: 00000000000006c0 x20: 000000000000000e x19: ffff800088baa334 x18: 1fffe000368261ce x17: ffff80008e4ed000 x16: ffff80008a8310f8 x15: 0000000000000001 x14: 1ffff00012df2d58 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000001 x10: 0000000000ff0100 x9 : e28a51f1087e8400 x8 : e28a51f1087e8400 x7 : ffff80008028f8d0 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800082b78714 x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000089 Call trace: skb_panic net/core/skbuff.c:189 [inline] skb_under_panic+0x13c/0x140 net/core/skbuff.c:203 skb_push+0xf0/0x108 net/core/skbuff.c:2451 eth_header+0x44/0x1f8 net/ethernet/eth.c:83 dev_hard_header include/linux/netdevice.h:3188 [inline] llc_mac_hdr_init+0x110/0x17c net/llc/llc_output.c:33 llc_sap_action_send_xid_c+0x170/0x344 net/llc/llc_s_ac.c:85 llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [inline] llc_sap_next_state net/llc/llc_sap.c:182 [inline] llc_sap_state_process+0x1ec/0x774 net/llc/llc_sap.c:209 llc_build_and_send_xid_pkt+0x12c/0x1c0 net/llc/llc_sap.c:270 llc_ui_sendmsg+0x7bc/0xb1c net/llc/af_llc.c:997 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_sendmsg+0x194/0x274 net/socket.c:767 splice_to_socket+0x7cc/0xd58 fs/splice.c:881 do_splice_from fs/splice.c:933 [inline] direct_splice_actor+0xe4/0x1c0 fs/splice.c:1142 splice_direct_to_actor+0x2a0/0x7e4 fs/splice.c:1088 do_splice_direct+0x20c/0x348 fs/splice.c:1194 do_sendfile+0x4bc/0xc70 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __arm64_sys_sendfile64+0x160/0x3b4 fs/read_write.c:1308 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 Code: aa1803e6 aa1903e7 a90023f5 94792f6a (d4210000) Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-and-tested-by: syzbot+2a7024e9502df538e8ef@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240118183625.4007013-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
syzbot was able to trick llc_ui_sendmsg(), allocating an skb with no
headroom, but subsequently trying to push 14 bytes of Ethernet header [1]

Like some others, llc_ui_sendmsg() releases the socket lock before
calling sock_alloc_send_skb().
Then it acquires it again, but does not redo all the sanity checks
that were performed.

This fix:

- Uses LL_RESERVED_SPACE() to reserve space.
- Check all conditions again after socket lock is held again.
- Do not account Ethernet header for mtu limitation.

[1]

skbuff: skb_under_panic: text:ffff800088baa334 len:1514 put:14 head:ffff0000c9c37000 data:ffff0000c9c36ff2 tail:0x5dc end:0x6c0 dev:bond0

 kernel BUG at net/core/skbuff.c:193 !
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6875 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00101-g0802e17d9aca-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : skb_panic net/core/skbuff.c:189 [inline]
 pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
 lr : skb_panic net/core/skbuff.c:189 [inline]
 lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
sp : ffff800096f97000
x29: ffff800096f97010 x28: ffff80008cc8d668 x27: dfff800000000000
x26: ffff0000cb970c90 x25: 00000000000005dc x24: ffff0000c9c36ff2
x23: ffff0000c9c37000 x22: 00000000000005ea x21: 00000000000006c0
x20: 000000000000000e x19: ffff800088baa334 x18: 1fffe000368261ce
x17: ffff80008e4ed000 x16: ffff80008a8310f8 x15: 0000000000000001
x14: 1ffff00012df2d58 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000ff0100 x9 : e28a51f1087e8400
x8 : e28a51f1087e8400 x7 : ffff80008028f8d0 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800082b78714
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000089
Call trace:
  skb_panic net/core/skbuff.c:189 [inline]
  skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
  skb_push+0xf0/0x108 net/core/skbuff.c:2451
  eth_header+0x44/0x1f8 net/ethernet/eth.c:83
  dev_hard_header include/linux/netdevice.h:3188 [inline]
  llc_mac_hdr_init+0x110/0x17c net/llc/llc_output.c:33
  llc_sap_action_send_xid_c+0x170/0x344 net/llc/llc_s_ac.c:85
  llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [inline]
  llc_sap_next_state net/llc/llc_sap.c:182 [inline]
  llc_sap_state_process+0x1ec/0x774 net/llc/llc_sap.c:209
  llc_build_and_send_xid_pkt+0x12c/0x1c0 net/llc/llc_sap.c:270
  llc_ui_sendmsg+0x7bc/0xb1c net/llc/af_llc.c:997
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg net/socket.c:745 [inline]
  sock_sendmsg+0x194/0x274 net/socket.c:767
  splice_to_socket+0x7cc/0xd58 fs/splice.c:881
  do_splice_from fs/splice.c:933 [inline]
  direct_splice_actor+0xe4/0x1c0 fs/splice.c:1142
  splice_direct_to_actor+0x2a0/0x7e4 fs/splice.c:1088
  do_splice_direct+0x20c/0x348 fs/splice.c:1194
  do_sendfile+0x4bc/0xc70 fs/read_write.c:1254
  __do_sys_sendfile64 fs/read_write.c:1322 [inline]
  __se_sys_sendfile64 fs/read_write.c:1308 [inline]
  __arm64_sys_sendfile64+0x160/0x3b4 fs/read_write.c:1308
  __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
  invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
  el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
  do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
  el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
  el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
  el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595
Code: aa1803e6 aa1903e7 a90023f5 94792f6a (d4210000)

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+2a7024e9502df538e8ef@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240118183625.4007013-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
llc: verify mac len before reading mac header 2023-11-02T05:21:32+00:00 Willem de Bruijn willemb@google.com 2023-10-25T23:42:38+00:00 7b3ba18703a63f6fd487183b9262b08e5632da1b LLC reads the mac header with eth_hdr without verifying that the skb has an Ethernet header. Syzbot was able to enter llc_rcv on a tun device. Tun can insert packets without mac len and with user configurable skb->protocol (passing a tun_pi header when not configuring IFF_NO_PI). BUG: KMSAN: uninit-value in llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline] BUG: KMSAN: uninit-value in llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111 llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline] llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111 llc_rcv+0xc5d/0x14a0 net/llc/llc_input.c:218 __netif_receive_skb_one_core net/core/dev.c:5523 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5637 netif_receive_skb_internal net/core/dev.c:5723 [inline] netif_receive_skb+0x58/0x660 net/core/dev.c:5782 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555 tun_get_user+0x54c5/0x69c0 drivers/net/tun.c:2002 Add a mac_len test before all three eth_hdr(skb) calls under net/llc. There are further uses in include/net/llc_pdu.h. All these are protected by a test skb->protocol == ETH_P_802_2. Which does not protect against this tun scenario. But the mac_len test added in this patch in llc_fixup_skb will indirectly protect those too. That is called from llc_rcv before any other LLC code. It is tempting to just add a blanket mac_len check in llc_rcv, but not sure whether that could break valid LLC paths that do not assume an Ethernet header. 802.2 LLC may be used on top of non-802.3 protocols in principle. The below referenced commit shows that used to, on top of Token Ring. At least one of the three eth_hdr uses goes back to before the start of git history. But the one that syzbot exercises is introduced in this commit. That commit is old enough (2008), that effectively all stable kernels should receive this. Fixes: f83f1768f833 ("[LLC]: skb allocation size for responses") Reported-by: syzbot+a8c7be6dee0de1b669cc@syzkaller.appspotmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20231025234251.3796495-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
LLC reads the mac header with eth_hdr without verifying that the skb
has an Ethernet header.

Syzbot was able to enter llc_rcv on a tun device. Tun can insert
packets without mac len and with user configurable skb->protocol
(passing a tun_pi header when not configuring IFF_NO_PI).

    BUG: KMSAN: uninit-value in llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline]
    BUG: KMSAN: uninit-value in llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111
    llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline]
    llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111
    llc_rcv+0xc5d/0x14a0 net/llc/llc_input.c:218
    __netif_receive_skb_one_core net/core/dev.c:5523 [inline]
    __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5637
    netif_receive_skb_internal net/core/dev.c:5723 [inline]
    netif_receive_skb+0x58/0x660 net/core/dev.c:5782
    tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555
    tun_get_user+0x54c5/0x69c0 drivers/net/tun.c:2002

Add a mac_len test before all three eth_hdr(skb) calls under net/llc.

There are further uses in include/net/llc_pdu.h. All these are
protected by a test skb->protocol == ETH_P_802_2. Which does not
protect against this tun scenario.

But the mac_len test added in this patch in llc_fixup_skb will
indirectly protect those too. That is called from llc_rcv before any
other LLC code.

It is tempting to just add a blanket mac_len check in llc_rcv, but
not sure whether that could break valid LLC paths that do not assume
an Ethernet header. 802.2 LLC may be used on top of non-802.3
protocols in principle. The below referenced commit shows that used
to, on top of Token Ring.

At least one of the three eth_hdr uses goes back to before the start
of git history. But the one that syzbot exercises is introduced in
this commit. That commit is old enough (2008), that effectively all
stable kernels should receive this.

Fixes: f83f1768f833 ("[LLC]: skb allocation size for responses")
Reported-by: syzbot+a8c7be6dee0de1b669cc@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231025234251.3796495-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/llc/llc_conn.c: fix 4 instances of -Wmissing-variable-declarations 2023-08-09T22:34:28+00:00 Nick Desaulniers ndesaulniers@google.com 2023-08-08T16:43:09+00:00 fa1891aeb7620b51992d0db86c72c0cd3cf114ab I'm looking to enable -Wmissing-variable-declarations behind W=1. 0day bot spotted the following instances: net/llc/llc_conn.c:44:5: warning: no previous extern declaration for non-static variable 'sysctl_llc2_ack_timeout' [-Wmissing-variable-declarations] 44 | int sysctl_llc2_ack_timeout = LLC2_ACK_TIME * HZ; | ^ net/llc/llc_conn.c:44:1: note: declare 'static' if the variable is not intended to be used outside of this translation unit 44 | int sysctl_llc2_ack_timeout = LLC2_ACK_TIME * HZ; | ^ net/llc/llc_conn.c:45:5: warning: no previous extern declaration for non-static variable 'sysctl_llc2_p_timeout' [-Wmissing-variable-declarations] 45 | int sysctl_llc2_p_timeout = LLC2_P_TIME * HZ; | ^ net/llc/llc_conn.c:45:1: note: declare 'static' if the variable is not intended to be used outside of this translation unit 45 | int sysctl_llc2_p_timeout = LLC2_P_TIME * HZ; | ^ net/llc/llc_conn.c:46:5: warning: no previous extern declaration for non-static variable 'sysctl_llc2_rej_timeout' [-Wmissing-variable-declarations] 46 | int sysctl_llc2_rej_timeout = LLC2_REJ_TIME * HZ; | ^ net/llc/llc_conn.c:46:1: note: declare 'static' if the variable is not intended to be used outside of this translation unit 46 | int sysctl_llc2_rej_timeout = LLC2_REJ_TIME * HZ; | ^ net/llc/llc_conn.c:47:5: warning: no previous extern declaration for non-static variable 'sysctl_llc2_busy_timeout' [-Wmissing-variable-declarations] 47 | int sysctl_llc2_busy_timeout = LLC2_BUSY_TIME * HZ; | ^ net/llc/llc_conn.c:47:1: note: declare 'static' if the variable is not intended to be used outside of this translation unit 47 | int sysctl_llc2_busy_timeout = LLC2_BUSY_TIME * HZ; | ^ These symbols are referenced by more than one translation unit, so make include the correct header for their declarations. Finally, sort the list of includes to help keep them tidy. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/llvm/202308081000.tTL1ElTr-lkp@intel.com/ Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230808-llc_static-v1-1-c140c4c297e4@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
I'm looking to enable -Wmissing-variable-declarations behind W=1. 0day
bot spotted the following instances:

  net/llc/llc_conn.c:44:5: warning: no previous extern declaration for
  non-static variable 'sysctl_llc2_ack_timeout'
  [-Wmissing-variable-declarations]
  44 | int sysctl_llc2_ack_timeout = LLC2_ACK_TIME * HZ;
     |     ^
  net/llc/llc_conn.c:44:1: note: declare 'static' if the variable is not
  intended to be used outside of this translation unit
  44 | int sysctl_llc2_ack_timeout = LLC2_ACK_TIME * HZ;
     | ^
  net/llc/llc_conn.c:45:5: warning: no previous extern declaration for
  non-static variable 'sysctl_llc2_p_timeout'
  [-Wmissing-variable-declarations]
  45 | int sysctl_llc2_p_timeout = LLC2_P_TIME * HZ;
     |     ^
  net/llc/llc_conn.c:45:1: note: declare 'static' if the variable is not
  intended to be used outside of this translation unit
  45 | int sysctl_llc2_p_timeout = LLC2_P_TIME * HZ;
     | ^
  net/llc/llc_conn.c:46:5: warning: no previous extern declaration for
  non-static variable 'sysctl_llc2_rej_timeout'
  [-Wmissing-variable-declarations]
  46 | int sysctl_llc2_rej_timeout = LLC2_REJ_TIME * HZ;
     |     ^
  net/llc/llc_conn.c:46:1: note: declare 'static' if the variable is not
  intended to be used outside of this translation unit
  46 | int sysctl_llc2_rej_timeout = LLC2_REJ_TIME * HZ;
     | ^
  net/llc/llc_conn.c:47:5: warning: no previous extern declaration for
  non-static variable 'sysctl_llc2_busy_timeout'
  [-Wmissing-variable-declarations]
  47 | int sysctl_llc2_busy_timeout = LLC2_BUSY_TIME * HZ;
     |     ^
  net/llc/llc_conn.c:47:1: note: declare 'static' if the variable is not
  intended to be used outside of this translation unit
  47 | int sysctl_llc2_busy_timeout = LLC2_BUSY_TIME * HZ;
     | ^

These symbols are referenced by more than one translation unit, so make
include the correct header for their declarations. Finally, sort the
list of includes to help keep them tidy.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/llvm/202308081000.tTL1ElTr-lkp@intel.com/
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230808-llc_static-v1-1-c140c4c297e4@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
llc: Don't drop packet from non-root netns. 2023-07-20T08:46:28+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2023-07-18T17:41:51+00:00 6631463b6e6673916d2481f692938f393148aa82 Now these upper layer protocol handlers can be called from llc_rcv() as sap->rcv_func(), which is registered by llc_sap_open(). * function which is passed to register_8022_client() -> no in-kernel user calls register_8022_client(). * snap_rcv() `- proto->rcvfunc() : registered by register_snap_client() -> aarp_rcv() and atalk_rcv() drop packets from non-root netns * stp_pdu_rcv() `- garp_protos[]->rcv() : registered by stp_proto_register() -> garp_pdu_rcv() and br_stp_rcv() are netns-aware So, we can safely remove the netns restriction in llc_rcv(). Fixes: e730c15519d0 ("[NET]: Make packet reception network namespace safe") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Now these upper layer protocol handlers can be called from llc_rcv()
as sap->rcv_func(), which is registered by llc_sap_open().

  * function which is passed to register_8022_client()
    -> no in-kernel user calls register_8022_client().

  * snap_rcv()
    `- proto->rcvfunc() : registered by register_snap_client()
       -> aarp_rcv() and atalk_rcv() drop packets from non-root netns

  * stp_pdu_rcv()
    `- garp_protos[]->rcv() : registered by stp_proto_register()
       -> garp_pdu_rcv() and br_stp_rcv() are netns-aware

So, we can safely remove the netns restriction in llc_rcv().

Fixes: e730c15519d0 ("[NET]: Make packet reception network namespace safe")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
llc: Check netns in llc_estab_match() and llc_listener_match(). 2023-07-20T08:46:28+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2023-07-18T17:41:50+00:00 97b1d320f48c21e40cc42b4ac033f2520f9ecc5c We will remove this restriction in llc_rcv() in the following patch, which means that the protocol handler must be aware of netns. if (!net_eq(dev_net(dev), &init_net)) goto drop; llc_rcv() fetches llc_type_handlers[llc_pdu_type(skb) - 1] and calls it if not NULL. If the PDU type is LLC_DEST_CONN, llc_conn_handler() is called to pass skb to corresponding sockets. Then, we must look up a proper socket in the same netns with skb->dev. llc_conn_handler() calls __llc_lookup() to look up a established or litening socket by __llc_lookup_established() and llc_lookup_listener(). Both functions iterate on a list and call llc_estab_match() or llc_listener_match() to check if the socket is the correct destination. However, these functions do not check netns. Also, bind() and connect() call llc_establish_connection(), which finally calls __llc_lookup_established(), to check if there is a conflicting socket. Let's test netns in llc_estab_match() and llc_listener_match(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
We will remove this restriction in llc_rcv() in the following patch,
which means that the protocol handler must be aware of netns.

        if (!net_eq(dev_net(dev), &init_net))
                goto drop;

llc_rcv() fetches llc_type_handlers[llc_pdu_type(skb) - 1] and calls it
if not NULL.

If the PDU type is LLC_DEST_CONN, llc_conn_handler() is called to pass
skb to corresponding sockets.  Then, we must look up a proper socket in
the same netns with skb->dev.

llc_conn_handler() calls __llc_lookup() to look up a established or
litening socket by __llc_lookup_established() and llc_lookup_listener().

Both functions iterate on a list and call llc_estab_match() or
llc_listener_match() to check if the socket is the correct destination.
However, these functions do not check netns.

Also, bind() and connect() call llc_establish_connection(), which
finally calls __llc_lookup_established(), to check if there is a
conflicting socket.

Let's test netns in llc_estab_match() and llc_listener_match().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
llc: Check netns in llc_dgram_match(). 2023-07-20T08:46:28+00:00 Kuniyuki Iwashima kuniyu@amazon.com 2023-07-18T17:41:49+00:00 9b64e93e83c2145a750e780198b41d612e3dfa5d We will remove this restriction in llc_rcv() soon, which means that the protocol handler must be aware of netns. if (!net_eq(dev_net(dev), &init_net)) goto drop; llc_rcv() fetches llc_type_handlers[llc_pdu_type(skb) - 1] and calls it if not NULL. If the PDU type is LLC_DEST_SAP, llc_sap_handler() is called to pass skb to corresponding sockets. Then, we must look up a proper socket in the same netns with skb->dev. If the destination is a multicast address, llc_sap_handler() calls llc_sap_mcast(). It calculates a hash based on DSAP and skb->dev->ifindex, iterates on a socket list, and calls llc_mcast_match() to check if the socket is the correct destination. Then, llc_mcast_match() checks if skb->dev matches with llc_sk(sk)->dev. So, we need not check netns here. OTOH, if the destination is a unicast address, llc_sap_handler() calls llc_lookup_dgram() to look up a socket, but it does not check the netns. Therefore, we need to add netns check in llc_lookup_dgram(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
We will remove this restriction in llc_rcv() soon, which means that the
protocol handler must be aware of netns.

	if (!net_eq(dev_net(dev), &init_net))
		goto drop;

llc_rcv() fetches llc_type_handlers[llc_pdu_type(skb) - 1] and calls it
if not NULL.

If the PDU type is LLC_DEST_SAP, llc_sap_handler() is called to pass skb
to corresponding sockets.  Then, we must look up a proper socket in the
same netns with skb->dev.

If the destination is a multicast address, llc_sap_handler() calls
llc_sap_mcast().  It calculates a hash based on DSAP and skb->dev->ifindex,
iterates on a socket list, and calls llc_mcast_match() to check if the
socket is the correct destination.  Then, llc_mcast_match() checks if
skb->dev matches with llc_sk(sk)->dev.  So, we need not check netns here.

OTOH, if the destination is a unicast address, llc_sap_handler() calls
llc_lookup_dgram() to look up a socket, but it does not check the netns.

Therefore, we need to add netns check in llc_lookup_dgram().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24T22:50:13+00:00 David Howells dhowells@redhat.com 2023-06-23T22:55:12+00:00 dc97391e661009eab46783030d2404c9b6e6f2e7 Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: deal with most data-races in sk_wait_event() 2023-05-10T09:03:32+00:00 Eric Dumazet edumazet@google.com 2023-05-09T18:29:48+00:00 d0ac89f6f9879fae316c155de77b5173b3e2c9c9 __condition is evaluated twice in sk_wait_event() macro. First invocation is lockless, and reads can race with writes, as spotted by syzbot. BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1: tcp_disconnect+0x2cd/0xdb0 inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911 __sys_shutdown_sock net/socket.c:2343 [inline] __sys_shutdown net/socket.c:2355 [inline] __do_sys_shutdown net/socket.c:2363 [inline] __se_sys_shutdown+0xf8/0x140 net/socket.c:2361 __x64_sys_shutdown+0x31/0x40 net/socket.c:2361 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0: sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75 tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x246/0x300 net/socket.c:2142 __do_sys_sendto net/socket.c:2154 [inline] __se_sys_sendto net/socket.c:2150 [inline] __x64_sys_sendto+0x78/0x90 net/socket.c:2150 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00000000 -> 0x00000068 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
__condition is evaluated twice in sk_wait_event() macro.

First invocation is lockless, and reads can race with writes,
as spotted by syzbot.

BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
tcp_disconnect+0x2cd/0xdb0
inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
__sys_shutdown_sock net/socket.c:2343 [inline]
__sys_shutdown net/socket.c:2355 [inline]
__do_sys_shutdown net/socket.c:2363 [inline]
__se_sys_shutdown+0xf8/0x140 net/socket.c:2361
__x64_sys_shutdown+0x31/0x40 net/socket.c:2361
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
__sys_sendto+0x246/0x300 net/socket.c:2142
__do_sys_sendto net/socket.c:2154 [inline]
__se_sys_sendto net/socket.c:2150 [inline]
__x64_sys_sendto+0x78/0x90 net/socket.c:2150
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000068

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>