1. 29 Jan, 2020 1 commit
    • Martin Schiller's avatar
      net/x25: fix nonblocking connect · c4efc614
      Martin Schiller authored
      commit e21dba7a
      
       upstream.
      
      This patch fixes 2 issues in x25_connect():
      
      1. It makes absolutely no sense to reset the neighbour and the
      connection state after a (successful) nonblocking call of x25_connect.
      This prevents any connection from being established, since the response
      (call accept) cannot be processed.
      
      2. Any further calls to x25_connect() while a call is pending should
      simply return, instead of creating new Call Request (on different
      logical channels).
      
      This patch should also fix the "KASAN: null-ptr-deref Write in
      x25_connect" and "BUG: unable to handle kernel NULL pointer dereference
      in x25_connect" bugs reported by syzbot.
      Signed-off-by: default avatarMartin Schiller <ms@dev.tdt.de>
      Reported-by: syzbot+429c200ffc8772bfe070@syzkaller.appspotmail.com
      Reported-by: syzbot+eec0c87f31a7c3b66f7b@syzkaller.appspotmail.com
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c4efc614
  2. 21 Dec, 2019 2 commits
  3. 19 Mar, 2019 3 commits
    • Eric Dumazet's avatar
      net/x25: fix a race in x25_bind() · 92382cd9
      Eric Dumazet authored
      [ Upstream commit 797a22bd ]
      
      syzbot was able to trigger another soft lockup [1]
      
      I first thought it was the O(N^2) issue I mentioned in my
      prior fix (f657d22ee1f "net/x25: do not hold the cpu
      too long in x25_new_lci()"), but I eventually found
      that x25_bind() was not checking SOCK_ZAPPED state under
      socket lock protection.
      
      This means that multiple threads can end up calling
      x25_insert_socket() for the same socket, and corrupt x25_list
      
      [1]
      watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz-executor.2:10492]
      Modules linked in:
      irq event stamp: 27515
      hardirqs last  enabled at (27514): [<ffffffff81006673>] trace_hardirqs_on_thunk+0x1a/0x1c
      hardirqs last disabled at (27515): [<ffffffff8100668f>] trace_hardirqs_off_thunk+0x1a/0x1c
      softirqs last  enabled at (32): [<ffffffff8632ee73>] x25_get_neigh+0xa3/0xd0 net/x25/x25_link.c:336
      softirqs last disabled at (34): [<ffffffff86324bc3>] x25_find_socket+0x23/0x140 net/x25/af_x25.c:341
      CPU: 0 PID: 10492 Comm: syz-executor.2 Not tainted 5.0.0-rc7+ #88
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x50 kernel/kcov.c:97
      Code: f4 ff ff ff e8 11 9f ea ff 48 c7 05 12 fb e5 08 00 00 00 00 e9 c8 e9 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 <48> 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 38 0c 92 7e 81 e2
      RSP: 0018:ffff88806e94fc48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
      RAX: 1ffff1100d84dac5 RBX: 0000000000000001 RCX: ffffc90006197000
      RDX: 0000000000040000 RSI: ffffffff86324bf3 RDI: ffff88806c26d628
      RBP: ffff88806e94fc48 R08: ffff88806c1c6500 R09: fffffbfff1282561
      R10: fffffbfff1282560 R11: ffffffff89412b03 R12: ffff88806c26d628
      R13: ffff888090455200 R14: dffffc0000000000 R15: 0000000000000000
      FS:  00007f3a107e4700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007f3a107e3db8 CR3: 00000000a5544000 CR4: 00000000001406f0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       __x25_find_socket net/x25/af_x25.c:327 [inline]
       x25_find_socket+0x7d/0x140 net/x25/af_x25.c:342
       x25_new_lci net/x25/af_x25.c:355 [inline]
       x25_connect+0x380/0xde0 net/x25/af_x25.c:784
       __sys_connect+0x266/0x330 net/socket.c:1662
       __do_sys_connect net/socket.c:1673 [inline]
       __se_sys_connect net/socket.c:1670 [inline]
       __x64_sys_connect+0x73/0xb0 net/socket.c:1670
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x457e29
      Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007f3a107e3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
      RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e29
      RDX: 0000000000000012 RSI: 0000000020000200 RDI: 0000000000000005
      RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3a107e46d4
      R13: 00000000004be362 R14: 00000000004ceb98 R15: 00000000ffffffff
      Sending NMI from CPU 0 to CPUs 1:
      NMI backtrace for cpu 1
      CPU: 1 PID: 10493 Comm: syz-executor.3 Not tainted 5.0.0-rc7+ #88
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
      RIP: 0010:queued_write_lock_slowpath+0x143/0x290 kernel/locking/qrwlock.c:86
      Code: 4c 8d 2c 01 41 83 c7 03 41 0f b6 45 00 41 38 c7 7c 08 84 c0 0f 85 0c 01 00 00 8b 03 3d 00 01 00 00 74 1a f3 90 41 0f b6 55 00 <41> 38 d7 7c eb 84 d2 74 e7 48 89 df e8 cc aa 4e 00 eb dd be 04 00
      RSP: 0018:ffff888085c47bd8 EFLAGS: 00000206
      RAX: 0000000000000300 RBX: ffffffff89412b00 RCX: 1ffffffff1282560
      RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff89412b00
      RBP: ffff888085c47c70 R08: 1ffffffff1282560 R09: fffffbfff1282561
      R10: fffffbfff1282560 R11: ffffffff89412b03 R12: 00000000000000ff
      R13: fffffbfff1282560 R14: 1ffff11010b88f7d R15: 0000000000000003
      FS:  00007fdd04086700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007fdd04064db8 CR3: 0000000090be0000 CR4: 00000000001406e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       queued_write_lock include/asm-generic/qrwlock.h:104 [inline]
       do_raw_write_lock+0x1d6/0x290 kernel/locking/spinlock_debug.c:203
       __raw_write_lock_bh include/linux/rwlock_api_smp.h:204 [inline]
       _raw_write_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:312
       x25_insert_socket+0x21/0xe0 net/x25/af_x25.c:267
       x25_bind+0x273/0x340 net/x25/af_x25.c:703
       __sys_bind+0x23f/0x290 net/socket.c:1481
       __do_sys_bind net/socket.c:1492 [inline]
       __se_sys_bind net/socket.c:1490 [inline]
       __x64_sys_bind+0x73/0xb0 net/socket.c:1490
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x457e29
      
      Fixes: 90c27297
      
       ("X.25 remove bkl in bind")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: andrew hendry <andrew.hendry@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      92382cd9
    • Eric Dumazet's avatar
      net/x25: reset state in x25_connect() · 0651889b
      Eric Dumazet authored
      [ Upstream commit ee74d0bd ]
      
      In case x25_connect() fails and frees the socket neighbour,
      we also need to undo the change done to x25->state.
      
      Before my last bug fix, we had use-after-free so this
      patch fixes a latent bug.
      
      syzbot report :
      
      kasan: CONFIG_KASAN_INLINE enabled
      kasan: GPF could be caused by NULL-ptr deref or user memory access
      general protection fault: 0000 [#1] PREEMPT SMP KASAN
      CPU: 1 PID: 16137 Comm: syz-executor.1 Not tainted 5.0.0+ #117
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      RIP: 0010:x25_write_internal+0x1e8/0xdf0 net/x25/x25_subr.c:173
      Code: 00 40 88 b5 e0 fe ff ff 0f 85 01 0b 00 00 48 8b 8b 80 04 00 00 48 ba 00 00 00 00 00 fc ff df 48 8d 79 1c 48 89 fe 48 c1 ee 03 <0f> b6 34 16 48 89 fa 83 e2 07 83 c2 03 40 38 f2 7c 09 40 84 f6 0f
      RSP: 0018:ffff888076717a08 EFLAGS: 00010207
      RAX: ffff88805f2f2292 RBX: ffff8880a0ae6000 RCX: 0000000000000000
      kobject: 'loop5' (0000000018d0d0ee): kobject_uevent_env
      RDX: dffffc0000000000 RSI: 0000000000000003 RDI: 000000000000001c
      RBP: ffff888076717b40 R08: ffff8880950e0580 R09: ffffed100be5e46d
      R10: ffffed100be5e46c R11: ffff88805f2f2363 R12: ffff888065579840
      kobject: 'loop5' (0000000018d0d0ee): fill_kobj_path: path = '/devices/virtual/block/loop5'
      R13: 1ffff1100ece2f47 R14: 0000000000000013 R15: 0000000000000013
      FS:  00007fb88cf43700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007f9a42a41028 CR3: 0000000087a67000 CR4: 00000000001406e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       x25_release+0xd0/0x340 net/x25/af_x25.c:658
       __sock_release+0xd3/0x2b0 net/socket.c:579
       sock_close+0x1b/0x30 net/socket.c:1162
       __fput+0x2df/0x8d0 fs/file_table.c:278
       ____fput+0x16/0x20 fs/file_table.c:309
       task_work_run+0x14a/0x1c0 kernel/task_work.c:113
       get_signal+0x1961/0x1d50 kernel/signal.c:2388
       do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816
       exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162
       prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
       syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
       do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x457f29
      Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007fb88cf42c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
      RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 0000000000457f29
      RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000004
      RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb88cf436d4
      R13: 00000000004be462 R14: 00000000004cec98 R15: 00000000ffffffff
      Modules linked in:
      
      Fixes: 95d6ebd5
      
       ("net/x25: fix use-after-free in x25_device_event()")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: andrew hendry <andrew.hendry@gmail.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0651889b
    • Eric Dumazet's avatar
      net/x25: fix use-after-free in x25_device_event() · 31235458
      Eric Dumazet authored
      [ Upstream commit 95d6ebd5
      
       ]
      
      In case of failure x25_connect() does a x25_neigh_put(x25->neighbour)
      but forgets to clear x25->neighbour pointer, thus triggering use-after-free.
      
      Since the socket is visible in x25_list, we need to hold x25_list_lock
      to protect the operation.
      
      syzbot report :
      
      BUG: KASAN: use-after-free in x25_kill_by_device net/x25/af_x25.c:217 [inline]
      BUG: KASAN: use-after-free in x25_device_event+0x296/0x2b0 net/x25/af_x25.c:252
      Read of size 8 at addr ffff8880a030edd0 by task syz-executor003/7854
      
      CPU: 0 PID: 7854 Comm: syz-executor003 Not tainted 5.0.0+ #97
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x172/0x1f0 lib/dump_stack.c:113
       print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
       kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
       __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
       x25_kill_by_device net/x25/af_x25.c:217 [inline]
       x25_device_event+0x296/0x2b0 net/x25/af_x25.c:252
       notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
       __raw_notifier_call_chain kernel/notifier.c:394 [inline]
       raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
       call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
       call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
       call_netdevice_notifiers net/core/dev.c:1765 [inline]
       __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:7607
       dev_change_flags+0x10d/0x170 net/core/dev.c:7643
       dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
       dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
       sock_do_ioctl+0x1bd/0x300 net/socket.c:995
       sock_ioctl+0x32b/0x610 net/socket.c:1096
       vfs_ioctl fs/ioctl.c:46 [inline]
       file_ioctl fs/ioctl.c:509 [inline]
       do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
       ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
       __do_sys_ioctl fs/ioctl.c:720 [inline]
       __se_sys_ioctl fs/ioctl.c:718 [inline]
       __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x4467c9
      Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007fdbea222d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
      RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 00000000004467c9
      RDX: 0000000020000340 RSI: 0000000000008914 RDI: 0000000000000003
      RBP: 00000000006dbc50 R08: 00007fdbea223700 R09: 0000000000000000
      R10: 00007fdbea223700 R11: 0000000000000246 R12: 00000000006dbc5c
      R13: 6000030030626669 R14: 0000000000000000 R15: 0000000030626669
      
      Allocated by task 7843:
       save_stack+0x45/0xd0 mm/kasan/common.c:73
       set_track mm/kasan/common.c:85 [inline]
       __kasan_kmalloc mm/kasan/common.c:495 [inline]
       __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
       kasan_kmalloc+0x9/0x10 mm/kasan/common.c:509
       kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3615
       kmalloc include/linux/slab.h:545 [inline]
       x25_link_device_up+0x46/0x3f0 net/x25/x25_link.c:249
       x25_device_event+0x116/0x2b0 net/x25/af_x25.c:242
       notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
       __raw_notifier_call_chain kernel/notifier.c:394 [inline]
       raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
       call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
       call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
       call_netdevice_notifiers net/core/dev.c:1765 [inline]
       __dev_notify_flags+0x121/0x2c0 net/core/dev.c:7605
       dev_change_flags+0x10d/0x170 net/core/dev.c:7643
       dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
       dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
       sock_do_ioctl+0x1bd/0x300 net/socket.c:995
       sock_ioctl+0x32b/0x610 net/socket.c:1096
       vfs_ioctl fs/ioctl.c:46 [inline]
       file_ioctl fs/ioctl.c:509 [inline]
       do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
       ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
       __do_sys_ioctl fs/ioctl.c:720 [inline]
       __se_sys_ioctl fs/ioctl.c:718 [inline]
       __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
      Freed by task 7865:
       save_stack+0x45/0xd0 mm/kasan/common.c:73
       set_track mm/kasan/common.c:85 [inline]
       __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
       kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
       __cache_free mm/slab.c:3494 [inline]
       kfree+0xcf/0x230 mm/slab.c:3811
       x25_neigh_put include/net/x25.h:253 [inline]
       x25_connect+0x8d8/0xde0 net/x25/af_x25.c:824
       __sys_connect+0x266/0x330 net/socket.c:1685
       __do_sys_connect net/socket.c:1696 [inline]
       __se_sys_connect net/socket.c:1693 [inline]
       __x64_sys_connect+0x73/0xb0 net/socket.c:1693
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
      The buggy address belongs to the object at ffff8880a030edc0
       which belongs to the cache kmalloc-256 of size 256
      The buggy address is located 16 bytes inside of
       256-byte region [ffff8880a030edc0, ffff8880a030eec0)
      The buggy address belongs to the page:
      page:ffffea000280c380 count:1 mapcount:0 mapping:ffff88812c3f07c0 index:0x0
      flags: 0x1fffc0000000200(slab)
      raw: 01fffc0000000200 ffffea0002806788 ffffea00027f0188 ffff88812c3f07c0
      raw: 0000000000000000 ffff8880a030e000 000000010000000c 0000000000000000
      page dumped because: kasan: bad access detected
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: syzbot+04babcefcd396fabec37@syzkaller.appspotmail.com
      Cc: andrew hendry <andrew.hendry@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      31235458
  4. 23 Feb, 2019 1 commit
    • Eric Dumazet's avatar
      net/x25: do not hold the cpu too long in x25_new_lci() · 4833df34
      Eric Dumazet authored
      commit cf657d22
      
       upstream.
      
      Due to quadratic behavior of x25_new_lci(), syzbot was able
      to trigger an rcu stall.
      
      Fix this by not blocking BH for the whole duration of
      the function, and inserting a reschedule point when possible.
      
      If we care enough, using a bitmap could get rid of the quadratic
      behavior.
      
      syzbot report :
      
      rcu: INFO: rcu_preempt self-detected stall on CPU
      rcu:    0-...!: (10500 ticks this GP) idle=4fa/1/0x4000000000000002 softirq=283376/283376 fqs=0
      rcu:     (t=10501 jiffies g=383105 q=136)
      rcu: rcu_preempt kthread starved for 10502 jiffies! g383105 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
      rcu: RCU grace-period kthread stack dump:
      rcu_preempt     I28928    10      2 0x80000000
      Call Trace:
       context_switch kernel/sched/core.c:2844 [inline]
       __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
       schedule+0x92/0x180 kernel/sched/core.c:3529
       schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803
       rcu_gp_fqs_loop kernel/rcu/tree.c:1948 [inline]
       rcu_gp_kthread+0x956/0x17a0 kernel/rcu/tree.c:2105
       kthread+0x357/0x430 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
      NMI backtrace for cpu 0
      CPU: 0 PID: 8759 Comm: syz-executor2 Not tainted 5.0.0-rc4+ #51
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       <IRQ>
       __dump_stack lib/dump_stack.c:77 [inline]
       dump_stack+0x172/0x1f0 lib/dump_stack.c:113
       nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
       nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
       arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
       trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
       rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree.c:1211
       print_cpu_stall kernel/rcu/tree.c:1348 [inline]
       check_cpu_stall kernel/rcu/tree.c:1422 [inline]
       rcu_pending kernel/rcu/tree.c:3018 [inline]
       rcu_check_callbacks.cold+0x500/0xa4a kernel/rcu/tree.c:2521
       update_process_times+0x32/0x80 kernel/time/timer.c:1635
       tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161
       tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271
       __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
       __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451
       hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
       smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060
       apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
       </IRQ>
      RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
      RIP: 0010:queued_write_lock_slowpath+0x13e/0x290 kernel/locking/qrwlock.c:86
      Code: 00 00 fc ff df 4c 8d 2c 01 41 83 c7 03 41 0f b6 45 00 41 38 c7 7c 08 84 c0 0f 85 0c 01 00 00 8b 03 3d 00 01 00 00 74 1a f3 90 <41> 0f b6 55 00 41 38 d7 7c eb 84 d2 74 e7 48 89 df e8 6c 0f 4f 00
      RSP: 0018:ffff88805f117bd8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
      RAX: 0000000000000300 RBX: ffffffff89413ba0 RCX: 1ffffffff1282774
      RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff89413ba0
      RBP: ffff88805f117c70 R08: 1ffffffff1282774 R09: fffffbfff1282775
      R10: fffffbfff1282774 R11: ffffffff89413ba3 R12: 00000000000000ff
      R13: fffffbfff1282774 R14: 1ffff1100be22f7d R15: 0000000000000003
       queued_write_lock include/asm-generic/qrwlock.h:104 [inline]
       do_raw_write_lock+0x1d6/0x290 kernel/locking/spinlock_debug.c:203
       __raw_write_lock_bh include/linux/rwlock_api_smp.h:204 [inline]
       _raw_write_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:312
       x25_insert_socket+0x21/0xe0 net/x25/af_x25.c:267
       x25_bind+0x273/0x340 net/x25/af_x25.c:705
       __sys_bind+0x23f/0x290 net/socket.c:1505
       __do_sys_bind net/socket.c:1516 [inline]
       __se_sys_bind net/socket.c:1514 [inline]
       __x64_sys_bind+0x73/0xb0 net/socket.c:1514
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x457e39
      Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007fafccd0dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
      RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39
      RDX: 0000000000000012 RSI: 0000000020000240 RDI: 0000000000000004
      RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000246 R12: 00007fafccd0e6d4
      R13: 00000000004bdf8b R14: 00000000004ce4b8 R15: 00000000ffffffff
      Sending NMI from CPU 0 to CPUs 1:
      NMI backtrace for cpu 1
      CPU: 1 PID: 8752 Comm: syz-executor4 Not tainted 5.0.0-rc4+ #51
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      RIP: 0010:__x25_find_socket+0x78/0x120 net/x25/af_x25.c:328
      Code: 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 a6 00 00 00 4d 8b 64 24 68 4d 85 e4 74 7f e8 03 97 3d fb 49 83 ec 68 74 74 e8 f8 96 3d fb <49> 8d bc 24 88 04 00 00 48 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 74
      RSP: 0018:ffff8880639efc58 EFLAGS: 00000246
      RAX: 0000000000040000 RBX: dffffc0000000000 RCX: ffffc9000e677000
      RDX: 0000000000040000 RSI: ffffffff863244b8 RDI: ffff88806a764628
      RBP: ffff8880639efc80 R08: ffff8880a80d05c0 R09: fffffbfff1282775
      R10: fffffbfff1282774 R11: ffffffff89413ba3 R12: ffff88806a7645c0
      R13: 0000000000000001 R14: ffff88809f29ac00 R15: 0000000000000000
      FS:  00007fe8d0c58700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 0000001b32823000 CR3: 00000000672eb000 CR4: 00000000001406e0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       x25_new_lci net/x25/af_x25.c:357 [inline]
       x25_connect+0x374/0xdf0 net/x25/af_x25.c:786
       __sys_connect+0x266/0x330 net/socket.c:1686
       __do_sys_connect net/socket.c:1697 [inline]
       __se_sys_connect net/socket.c:1694 [inline]
       __x64_sys_connect+0x73/0xb0 net/socket.c:1694
       do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe
      RIP: 0033:0x457e39
      Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007fe8d0c57c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
      RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39
      RDX: 0000000000000012 RSI: 0000000020000200 RDI: 0000000000000004
      RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8d0c586d4
      R13: 00000000004be378 R14: 00000000004ceb00 R15: 00000000ffffffff
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      Cc: Andrew Hendry <andrew.hendry@gmail.com>
      Cc: linux-x25@vger.kernel.org
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4833df34
  5. 13 Apr, 2018 1 commit
  6. 10 Sep, 2016 1 commit
  7. 11 May, 2015 1 commit
  8. 02 Mar, 2015 1 commit
  9. 24 Nov, 2014 1 commit
  10. 05 Nov, 2014 1 commit
    • David S. Miller's avatar
      net: Add and use skb_copy_datagram_msg() helper. · 51f3d02b
      David S. Miller authored
      
      
      This encapsulates all of the skb_copy_datagram_iovec() callers
      with call argument signature "skb, offset, msghdr->msg_iov, length".
      
      When we move to iov_iters in the networking, the iov_iter object will
      sit in the msghdr.
      
      Having a helper like this means there will be less places to touch
      during that transformation.
      
      Based upon descriptions and patch from Al Viro.
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      51f3d02b
  11. 11 Apr, 2014 1 commit
    • David S. Miller's avatar
      net: Fix use after free by removing length arg from sk_data_ready callbacks. · 676d2369
      David S. Miller authored
      
      
      Several spots in the kernel perform a sequence like:
      
      	skb_queue_tail(&sk->s_receive_queue, skb);
      	sk->sk_data_ready(sk, skb->len);
      
      But at the moment we place the SKB onto the socket receive queue it
      can be consumed and freed up.  So this skb->len access is potentially
      to freed up memory.
      
      Furthermore, the skb->len can be modified by the consumer so it is
      possible that the value isn't accurate.
      
      And finally, no actual implementation of this callback actually uses
      the length argument.  And since nobody actually cared about it's
      value, lots of call sites pass arbitrary values in such as '0' and
      even '1'.
      
      So just remove the length argument from the callback, that way there
      is no confusion whatsoever and all of these use-after-free cases get
      fixed as a side effect.
      
      Based upon a patch by Eric Dumazet and his suggestion to audit this
      issue tree-wide.
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      676d2369
  12. 19 Jan, 2014 1 commit
  13. 10 Dec, 2013 1 commit
  14. 21 Nov, 2013 1 commit
    • Hannes Frederic Sowa's avatar
      net: rework recvmsg handler msg_name and msg_namelen logic · f3d33426
      Hannes Frederic Sowa authored
      
      
      This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
      set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
      to return msg_name to the user.
      
      This prevents numerous uninitialized memory leaks we had in the
      recvmsg handlers and makes it harder for new code to accidentally leak
      uninitialized memory.
      
      Optimize for the case recvfrom is called with NULL as address. We don't
      need to copy the address at all, so set it to NULL before invoking the
      recvmsg handler. We can do so, because all the recvmsg handlers must
      cope with the case a plain read() is called on them. read() also sets
      msg_name to NULL.
      
      Also document these changes in include/linux/net.h as suggested by David
      Miller.
      
      Changes since RFC:
      
      Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
      non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
      affect sendto as it would bail out earlier while trying to copy-in the
      address. It also more naturally reflects the logic by the callers of
      verify_iovec.
      
      With this change in place I could remove "
      if (!uaddr || msg_sys->msg_namelen == 0)
      	msg->msg_name = NULL
      ".
      
      This change does not alter the user visible error logic as we ignore
      msg_namelen as long as msg_name is NULL.
      
      Also remove two unnecessary curly brackets in ___sys_recvmsg and change
      comments to netdev style.
      
      Cc: David Miller <davem@davemloft.net>
      Suggested-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f3d33426
  15. 02 Jul, 2013 1 commit
    • Dave Jones's avatar
      x25: Fix broken locking in ioctl error paths. · 4ccb93ce
      Dave Jones authored
      
      
      Two of the x25 ioctl cases have error paths that break out of the function without
      unlocking the socket, leading to this warning:
      
      ================================================
      [ BUG: lock held when returning to user space! ]
      3.10.0-rc7+ #36 Not tainted
      ------------------------------------------------
      trinity-child2/31407 is leaving the kernel with locks still held!
      1 lock held by trinity-child2/31407:
       #0:  (sk_lock-AF_X25){+.+.+.}, at: [<ffffffffa024b6da>] x25_ioctl+0x8a/0x740 [x25]
      Signed-off-by: default avatarDave Jones <davej@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4ccb93ce
  16. 28 May, 2013 1 commit
  17. 28 Feb, 2013 1 commit
    • Sasha Levin's avatar
      hlist: drop the node parameter from iterators · b67bfe0d
      Sasha Levin authored
      
      
      I'm not sure why, but the hlist for each entry iterators were conceived
      
              list_for_each_entry(pos, head, member)
      
      The hlist ones were greedy and wanted an extra parameter:
      
              hlist_for_each_entry(tpos, pos, head, member)
      
      Why did they need an extra pos parameter? I'm not quite sure. Not only
      they don't really need it, it also prevents the iterator from looking
      exactly like the list iterator, which is unfortunate.
      
      Besides the semantic patch, there was some manual work required:
      
       - Fix up the actual hlist iterators in linux/list.h
       - Fix up the declaration of other iterators based on the hlist ones.
       - A very small amount of places were using the 'node' parameter, this
       was modified to use 'obj->member' instead.
       - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
       properly, so those had to be fixed up manually.
      
      The semantic patch which is mostly the work of Peter Senna Tschudin is here:
      
      @@
      iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
      
      type T;
      expression a,c,d,e;
      identifier b;
      statement S;
      @@
      
      -T b;
          <+... when != b
      (
      hlist_for_each_entry(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue(a,
      - b,
      c) S
      |
      hlist_for_each_entry_from(a,
      - b,
      c) S
      |
      hlist_for_each_entry_rcu(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_rcu_bh(a,
      - b,
      c, d) S
      |
      hlist_for_each_entry_continue_rcu_bh(a,
      - b,
      c) S
      |
      for_each_busy_worker(a, c,
      - b,
      d) S
      |
      ax25_uid_for_each(a,
      - b,
      c) S
      |
      ax25_for_each(a,
      - b,
      c) S
      |
      inet_bind_bucket_for_each(a,
      - b,
      c) S
      |
      sctp_for_each_hentry(a,
      - b,
      c) S
      |
      sk_for_each(a,
      - b,
      c) S
      |
      sk_for_each_rcu(a,
      - b,
      c) S
      |
      sk_for_each_from
      -(a, b)
      +(a)
      S
      + sk_for_each_from(a) S
      |
      sk_for_each_safe(a,
      - b,
      c, d) S
      |
      sk_for_each_bound(a,
      - b,
      c) S
      |
      hlist_for_each_entry_safe(a,
      - b,
      c, d, e) S
      |
      hlist_for_each_entry_continue_rcu(a,
      - b,
      c) S
      |
      nr_neigh_for_each(a,
      - b,
      c) S
      |
      nr_neigh_for_each_safe(a,
      - b,
      c, d) S
      |
      nr_node_for_each(a,
      - b,
      c) S
      |
      nr_node_for_each_safe(a,
      - b,
      c, d) S
      |
      - for_each_gfn_sp(a, c, d, b) S
      + for_each_gfn_sp(a, c, d) S
      |
      - for_each_gfn_indirect_valid_sp(a, c, d, b) S
      + for_each_gfn_indirect_valid_sp(a, c, d) S
      |
      for_each_host(a,
      - b,
      c) S
      |
      for_each_host_safe(a,
      - b,
      c, d) S
      |
      for_each_mesh_entry(a,
      - b,
      c, d) S
      )
          ...+>
      
      [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
      [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
      [akpm@linux-foundation.org: checkpatch fixes]
      [akpm@linux-foundation.org: fix warnings]
      [akpm@linux-foudnation.org: redo intrusive kvm changes]
      Tested-by: default avatarPeter Senna Tschudin <peter.senna@gmail.com>
      Acked-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Marcelo Tosatti <mtosatti@redhat.com>
      Cc: Gleb Natapov <gleb@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b67bfe0d
  18. 16 Dec, 2011 1 commit
  19. 02 Nov, 2011 1 commit
    • Dave Jones's avatar
      x25: Fix NULL dereference in x25_recvmsg · 501e89d3
      Dave Jones authored
      commit cb101ed2
      
       in 3.0 introduced a bug in x25_recvmsg()
      When passed bogus junk from userspace, x25->neighbour can be NULL,
      as shown in this oops..
      
      BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
      IP: [<ffffffffa05482bd>] x25_recvmsg+0x4d/0x280 [x25]
      PGD 1015f3067 PUD 105072067 PMD 0
      Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
      CPU 0
      Pid: 27928, comm: iknowthis Not tainted 3.1.0+ #2 Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H
      RIP: 0010:[<ffffffffa05482bd>]  [<ffffffffa05482bd>] x25_recvmsg+0x4d/0x280 [x25]
      RSP: 0018:ffff88010c0b7cc8  EFLAGS: 00010282
      RAX: 0000000000000000 RBX: ffff88010c0b7d78 RCX: 0000000000000c02
      RDX: ffff88010c0b7d78 RSI: ffff88011c93dc00 RDI: ffff880103f667b0
      RBP: ffff88010c0b7d18 R08: 0000000000000000 R09: 0000000000000000
      R10: 0000000000000000 R11: 0000000000000000 R12: ffff880103f667b0
      R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
      FS:  00007f479ce7f700(0000) GS:ffff88012a600000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      CR2: 000000000000001c CR3: 000000010529e000 CR4: 00000000000006f0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
      Process iknowthis (pid: 27928, threadinfo ffff88010c0b6000, task ffff880103faa4f0)
      Stack:
       0000000000000c02 0000000000000c02 ffff88010c0b7d18 ffffff958153cb37
       ffffffff8153cb60 0000000000000c02 ffff88011c93dc00 0000000000000000
       0000000000000c02 ffff88010c0b7e10 ffff88010c0b7de8 ffffffff815372c2
      Call Trace:
       [<ffffffff8153cb60>] ? sock_update_classid+0xb0/0x180
       [<ffffffff815372c2>] sock_aio_read.part.10+0x142/0x150
       [<ffffffff812d6752>] ? inode_has_perm+0x62/0xa0
       [<ffffffff815372fd>] sock_aio_read+0x2d/0x40
       [<ffffffff811b05e2>] do_sync_read+0xd2/0x110
       [<ffffffff812d3796>] ? security_file_permission+0x96/0xb0
       [<ffffffff811b0a91>] ? rw_verify_area+0x61/0x100
       [<ffffffff811b103d>] vfs_read+0x16d/0x180
       [<ffffffff811b109d>] sys_read+0x4d/0x90
       [<ffffffff81657282>] system_call_fastpath+0x16/0x1b
      Code: 8b 66 20 4c 8b 32 48 89 d3 48 89 4d b8 45 89 c7 c7 45 cc 95 ff ff ff 4d 85 e4 0f 84 ed 01 00 00 49 8b 84 24 18 05 00 00 4c 89 e7
       78 1c 01 45 19 ed 31 f6 e8 d5 37 ff e0 41 0f b6 44 24 0e 41
      Signed-off-by: default avatarDave Jones <davej@redhat.com>
      Acked-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      501e89d3
  20. 17 Oct, 2011 3 commits
  21. 01 Jul, 2011 1 commit
  22. 05 Mar, 2011 1 commit
    • Arnd Bergmann's avatar
      x25: remove the BKL · 77b22836
      Arnd Bergmann authored
      
      
      This replaces all instances of lock_kernel in x25
      with lock_sock, taking care to release the socket
      lock around sleeping functions (sock_alloc_send_skb
      and skb_recv_datagram). It is not clear whether
      this is a correct solution, but it seem to be what
      other protocols do in the same situation.
      
      Includes a fix suggested by Eric Dumazet.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      Tested-by: default avatarAndrew Hendry <andrew.hendry@gmail.com>
      Cc: linux-x25@vger.kernel.org
      Cc: netdev@vger.kernel.org
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      77b22836
  23. 28 Nov, 2010 5 commits
  24. 19 Nov, 2010 4 commits
  25. 22 Sep, 2010 2 commits
  26. 15 Sep, 2010 2 commits