Hello, syzbot found the following crash on: HEAD commit: 85cb9287 net: rds: fix memory leak in rds_ib_flush_mr_pool git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=133e162ea00000 kernel config: https://syzkaller.appspot.com/x/.config?x=4f721a391cd46ea dashboard link: https://syzkaller.appspot.com/bug?extid=6eaef7158b19e3fec3a0 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+6eaef7158b19e3fec3a0@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123 Read of size 4 at addr ffff88807bd1a3c0 by task syz-executor.4/31693 CPU: 1 PID: 31693 Comm: syz-executor.4 Not tainted 5.2.0-rc2+ #43 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:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:94 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] refcount_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123 refcount_inc_checked+0x17/0x70 lib/refcount.c:156 sock_hold include/net/sock.h:654 [inline] nr_release+0x62/0x3b0 net/netrom/af_netrom.c:523 __sock_release+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffda8e7f4d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000412f61 RDX: 0000000000000000 RSI: ffffffff87168e98 RDI: 0000000000000004 RBP: 0000000000000001 R08: ffffffff81009897 R09: 0000000017981f41 R10: 00007ffda8e7f5b0 R11: 0000000000000293 R12: 000000000075c920 R13: 000000000075c920 R14: 000000000018a8f4 R15: 000000000075c10c Allocated by task 31694: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 __do_kmalloc mm/slab.c:3660 [inline] __kmalloc+0x15c/0x740 mm/slab.c:3669 kmalloc include/linux/slab.h:552 [inline] sk_prot_alloc+0x19c/0x2e0 net/core/sock.c:1608 sk_alloc+0x39/0xf70 net/core/sock.c:1662 nr_create+0xb9/0x5e0 net/netrom/af_netrom.c:436 __sock_create+0x3d8/0x730 net/socket.c:1430 sock_create net/socket.c:1481 [inline] __sys_socket+0x103/0x220 net/socket.c:1523 __do_sys_socket net/socket.c:1532 [inline] __se_sys_socket net/socket.c:1530 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1530 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 31693: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xcf/0x220 mm/slab.c:3755 sk_prot_free net/core/sock.c:1645 [inline] __sk_destruct+0x4f7/0x6e0 net/core/sock.c:1731 sk_destruct+0x7b/0x90 net/core/sock.c:1739 __sk_free+0xce/0x300 net/core/sock.c:1750 sk_free+0x42/0x50 net/core/sock.c:1761 sock_put include/net/sock.h:1728 [inline] nr_release+0x332/0x3b0 net/netrom/af_netrom.c:557 __sock_release+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88807bd1a340 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff88807bd1a340, ffff88807bd1ab40) The buggy address belongs to the page: page:ffffea0001ef4680 refcount:1 mapcount:0 mapping:ffff8880aa400c40 index:0xffff88807bd1b440 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002a48788 ffffea00018fc508 ffff8880aa400c40 raw: ffff88807bd1b440 ffff88807bd1a340 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807bd1a280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807bd1a300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ffff88807bd1a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807bd1a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807bd1a480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot has found a reproducer for the following crash on: HEAD commit: 192f0f8e Merge tag 'powerpc-5.3-1' of git://git.kernel.org.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=171bde00600000 kernel config: https://syzkaller.appspot.com/x/.config?x=87305c3ca9c25c70 dashboard link: https://syzkaller.appspot.com/bug?extid=6eaef7158b19e3fec3a0 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15882cd0600000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+6eaef7158b19e3fec3a0@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in atomic_read /./include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x81/0x200 /lib/refcount.c:123 Read of size 4 at addr ffff88807be6b6c0 by task syz-executor.0/11548 CPU: 0 PID: 11548 Comm: syz-executor.0 Not tainted 5.2.0+ #66 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+0xd4/0x306 /mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 /mm/kasan/report.c:482 kasan_report+0x12/0x20 /mm/kasan/common.c:612 check_memory_region_inline /mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 /mm/kasan/generic.c:192 __kasan_check_read+0x11/0x20 /mm/kasan/common.c:92 atomic_read /./include/asm-generic/atomic-instrumented.h:26 [inline] refcount_inc_not_zero_checked+0x81/0x200 /lib/refcount.c:123 refcount_inc_checked+0x17/0x70 /lib/refcount.c:156 sock_hold /./include/net/sock.h:649 [inline] nr_release+0x62/0x3e0 /net/netrom/af_netrom.c:520 __sock_release+0xce/0x280 /net/socket.c:586 sock_close+0x1e/0x30 /net/socket.c:1264 __fput+0x2ff/0x890 /fs/file_table.c:280 ____fput+0x16/0x20 /fs/file_table.c:313 task_work_run+0x145/0x1c0 /kernel/task_work.c:113 tracehook_notify_resume /./include/linux/tracehook.h:185 [inline] exit_to_usermode_loop+0x316/0x380 /arch/x86/entry/common.c:163 prepare_exit_to_usermode /arch/x86/entry/common.c:194 [inline] syscall_return_slowpath /arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413501 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffe5eb40550 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413501 RDX: 0000001b2be20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffe5eb40630 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760a68 R15: ffffffffffffffff Allocated by task 0: save_stack+0x23/0x90 /mm/kasan/common.c:69 set_track /mm/kasan/common.c:77 [inline] __kasan_kmalloc /mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 /mm/kasan/common.c:460 kasan_kmalloc+0x9/0x10 /mm/kasan/common.c:501 __do_kmalloc /mm/slab.c:3655 [inline] __kmalloc+0x163/0x780 /mm/slab.c:3664 kmalloc /./include/linux/slab.h:557 [inline] sk_prot_alloc+0x23a/0x310 /net/core/sock.c:1603 sk_alloc+0x39/0xf70 /net/core/sock.c:1657 nr_make_new /net/netrom/af_netrom.c:476 [inline] nr_rx_frame+0x733/0x1e80 /net/netrom/af_netrom.c:959 nr_loopback_timer+0x7b/0x170 /net/netrom/nr_loopback.c:59 call_timer_fn+0x1ac/0x780 /kernel/time/timer.c:1322 expire_timers /kernel/time/timer.c:1366 [inline] __run_timers /kernel/time/timer.c:1685 [inline] __run_timers /kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 /kernel/time/timer.c:1698 __do_softirq+0x262/0x98c /kernel/softirq.c:292 Freed by task 11551: save_stack+0x23/0x90 /mm/kasan/common.c:69 set_track /mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 /mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 /mm/kasan/common.c:457 __cache_free /mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 /mm/slab.c:3756 sk_prot_free /net/core/sock.c:1640 [inline] __sk_destruct+0x4f7/0x6e0 /net/core/sock.c:1726 sk_destruct+0x86/0xa0 /net/core/sock.c:1734 __sk_free+0xfb/0x360 /net/core/sock.c:1745 sk_free+0x42/0x50 /net/core/sock.c:1756 sock_put /./include/net/sock.h:1725 [inline] sock_efree+0x61/0x80 /net/core/sock.c:2042 skb_release_head_state+0xeb/0x260 /net/core/skbuff.c:652 skb_release_all+0x16/0x60 /net/core/skbuff.c:663 __kfree_skb /net/core/skbuff.c:679 [inline] kfree_skb /net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x3c0 /net/core/skbuff.c:691 nr_accept+0x570/0x720 /net/netrom/af_netrom.c:819 __sys_accept4+0x34e/0x6a0 /net/socket.c:1750 __do_sys_accept4 /net/socket.c:1785 [inline] __se_sys_accept4 /net/socket.c:1782 [inline] __x64_sys_accept4+0x97/0xf0 /net/socket.c:1782 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88807be6b640 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff88807be6b640, ffff88807be6be40) The buggy address belongs to the page: page:ffffea0001ef9a80 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001ef9708 ffffea0002453708 ffff8880aa400e00 raw: 0000000000000000 ffff88807be6a540 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807be6b580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807be6b600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ffff88807be6b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807be6b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807be6b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ ODEBUG: activate not available (active state 0) object type: timer_list hint: nr_t1timer_expiry+0x0/0x340 /net/netrom/nr_timer.c:157 WARNING: CPU: 0 PID: 11548 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Modules linked in: CPU: 0 PID: 11548 Comm: syz-executor.0 Tainted: G B 5.2.0+ #66 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Code: dd a0 48 c5 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd a0 48 c5 87 48 c7 c7 00 3e c5 87 e8 f0 b1 07 fe <0f> 0b 83 05 13 86 66 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3 RSP: 0018:ffff88809151faf0 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815c1016 RDI: ffffed10122a3f50 RBP: ffff88809151fb30 R08: ffff8880943fe300 R09: ffffed1015d040f1 R10: ffffed1015d040f0 R11: ffff8880ae820787 R12: 0000000000000001 R13: ffffffff88db4ca0 R14: ffffffff8161a860 R15: 1ffff110122a3f6c FS: 0000555555737940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fada90cddb8 CR3: 00000000a7f80000 CR4: 00000000001406f0 Call Trace: debug_object_activate+0x2e5/0x470 /lib/debugobjects.c:680 debug_timer_activate /kernel/time/timer.c:710 [inline] __mod_timer /kernel/time/timer.c:1035 [inline] mod_timer+0x452/0xc10 /kernel/time/timer.c:1096 sk_reset_timer+0x24/0x60 /net/core/sock.c:2821 nr_start_t1timer+0x6e/0xa0 /net/netrom/nr_timer.c:52 nr_release+0x1de/0x3e0 /net/netrom/af_netrom.c:537 __sock_release+0xce/0x280 /net/socket.c:586 sock_close+0x1e/0x30 /net/socket.c:1264 __fput+0x2ff/0x890 /fs/file_table.c:280 ____fput+0x16/0x20 /fs/file_table.c:313 task_work_run+0x145/0x1c0 /kernel/task_work.c:113 tracehook_notify_resume /./include/linux/tracehook.h:185 [inline] exit_to_usermode_loop+0x316/0x380 /arch/x86/entry/common.c:163 prepare_exit_to_usermode /arch/x86/entry/common.c:194 [inline] syscall_return_slowpath /arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413501 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffe5eb40550 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413501 RDX: 0000001b2be20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffe5eb40630 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760a68 R15: ffffffffffffffff irq event stamp: 1316 hardirqs last enabled at (1315): [<ffffffff873119e8>] __raw_spin_unlock_irq /./include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (1315): [<ffffffff873119e8>] _raw_spin_unlock_irq+0x28/0x90 /kernel/locking/spinlock.c:199 hardirqs last disabled at (1316): [<ffffffff8731216f>] __raw_spin_lock_irqsave /./include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (1316): [<ffffffff8731216f>] _raw_spin_lock_irqsave+0x6f/0xcd /kernel/locking/spinlock.c:159 softirqs last enabled at (1168): [<ffffffff812923fe>] memcpy /./include/linux/string.h:359 [inline] softirqs last enabled at (1168): [<ffffffff812923fe>] fpu__copy+0x17e/0x8c0 /arch/x86/kernel/fpu/core.c:195 softirqs last disabled at (1166): [<ffffffff81292327>] fpu__copy+0xa7/0x8c0 /arch/x86/kernel/fpu/core.c:183 ---[ end trace c9359faa0df5eab0 ]---
syzbot has bisected this bug to: commit c8c8218ec5af5d2598381883acbefbf604e56b5e Author: Cong Wang <xiyou.wangcong@gmail.com> Date: Thu Jun 27 21:30:58 2019 +0000 netrom: fix a memory leak in nr_rx_frame() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10a3bcd0600000 start commit: 192f0f8e Merge tag 'powerpc-5.3-1' of git://git.kernel.org.. git tree: net-next final crash: https://syzkaller.appspot.com/x/report.txt?x=12a3bcd0600000 console output: https://syzkaller.appspot.com/x/log.txt?x=14a3bcd0600000 kernel config: https://syzkaller.appspot.com/x/.config?x=87305c3ca9c25c70 dashboard link: https://syzkaller.appspot.com/bug?extid=6eaef7158b19e3fec3a0 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15882cd0600000 Reported-by: syzbot+6eaef7158b19e3fec3a0@syzkaller.appspotmail.com Fixes: c8c8218ec5af ("netrom: fix a memory leak in nr_rx_frame()") For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot has found a reproducer for the following crash on: HEAD commit: 3ea54d9b Merge tag 'docs-5.3-1' of git://git.lwn.net/linux git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=140a9794600000 kernel config: https://syzkaller.appspot.com/x/.config?x=4809ada7c73f0407 dashboard link: https://syzkaller.appspot.com/bug?extid=6eaef7158b19e3fec3a0 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=156f25a2600000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13fae0e8600000 The bug was bisected to: commit c8c8218ec5af5d2598381883acbefbf604e56b5e Author: Cong Wang <xiyou.wangcong@gmail.com> Date: Thu Jun 27 21:30:58 2019 +0000 netrom: fix a memory leak in nr_rx_frame() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10a3bcd0600000 final crash: https://syzkaller.appspot.com/x/report.txt?x=12a3bcd0600000 console output: https://syzkaller.appspot.com/x/log.txt?x=14a3bcd0600000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+6eaef7158b19e3fec3a0@syzkaller.appspotmail.com Fixes: c8c8218ec5af ("netrom: fix a memory leak in nr_rx_frame()") ================================================================== BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123 Read of size 4 at addr ffff888093589300 by task syz-executor118/6083 CPU: 1 PID: 6083 Comm: syz-executor118 Not tainted 5.3.0-rc1+ #85 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+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:612 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_read+0x11/0x20 mm/kasan/common.c:92 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] refcount_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123 refcount_inc_checked+0x17/0x70 lib/refcount.c:156 sock_hold include/net/sock.h:649 [inline] nr_release+0x62/0x3e0 net/netrom/af_netrom.c:520 __sock_release+0xce/0x280 net/socket.c:590 sock_close+0x1e/0x30 net/socket.c:1268 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x406901 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 24 1a 00 00 c3 48 83 ec 08 e8 6a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 b3 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffede643710 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000406901 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006dcc30 R08: 0000000120080522 R09: 0000000120080522 R10: 00007ffede643730 R11: 0000000000000293 R12: 00007ffede643760 R13: 0000000000000004 R14: 00000000006dcc3c R15: 0000000000000064 Allocated by task 0: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x163/0x770 mm/slab.c:3664 kmalloc include/linux/slab.h:557 [inline] sk_prot_alloc+0x23a/0x310 net/core/sock.c:1603 sk_alloc+0x39/0xf70 net/core/sock.c:1657 nr_make_new net/netrom/af_netrom.c:476 [inline] nr_rx_frame+0x733/0x1e73 net/netrom/af_netrom.c:959 nr_loopback_timer+0x7b/0x170 net/netrom/nr_loopback.c:59 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 Freed by task 6086: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 mm/kasan/common.c:457 __cache_free mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 mm/slab.c:3756 sk_prot_free net/core/sock.c:1640 [inline] __sk_destruct+0x4f7/0x6e0 net/core/sock.c:1726 sk_destruct+0x86/0xa0 net/core/sock.c:1734 __sk_free+0xfb/0x360 net/core/sock.c:1745 sk_free+0x42/0x50 net/core/sock.c:1756 sock_put include/net/sock.h:1725 [inline] sock_efree+0x61/0x80 net/core/sock.c:2042 skb_release_head_state+0xeb/0x250 net/core/skbuff.c:652 skb_release_all+0x16/0x60 net/core/skbuff.c:663 __kfree_skb net/core/skbuff.c:679 [inline] kfree_skb net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x3c0 net/core/skbuff.c:691 nr_accept+0x56e/0x700 net/netrom/af_netrom.c:819 __sys_accept4+0x34e/0x6a0 net/socket.c:1754 __do_sys_accept4 net/socket.c:1789 [inline] __se_sys_accept4 net/socket.c:1786 [inline] __x64_sys_accept4+0x97/0xf0 net/socket.c:1786 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888093589280 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff888093589280, ffff888093589a80) The buggy address belongs to the page: page:ffffea00024d6200 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea000228a508 ffffea00024cef08 ffff8880aa400e00 raw: 0000000000000000 ffff888093588180 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888093589200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888093589280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888093589300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888093589380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888093589400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ ODEBUG: activate not available (active state 0) object type: timer_list hint: nr_t1timer_expiry+0x0/0x340 net/netrom/nr_timer.c:157 WARNING: CPU: 1 PID: 6083 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 lib/debugobjects.c:481 Modules linked in: CPU: 1 PID: 6083 Comm: syz-executor118 Tainted: G B 5.3.0-rc1+ #85 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x168/0x250 lib/debugobjects.c:481 Code: dd e0 30 c6 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd e0 30 c6 87 48 c7 c7 e0 25 c6 87 e8 50 c3 05 fe <0f> 0b 83 05 33 4d 67 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3 RSP: 0018:ffff888089fbfaf0 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815c5bd6 RDI: ffffed10113f7f50 RBP: ffff888089fbfb30 R08: ffff8880924ea140 R09: fffffbfff134ac80 R10: fffffbfff134ac7f R11: ffffffff89a563ff R12: 0000000000000001 R13: ffffffff88db6460 R14: ffffffff8161fa40 R15: 1ffff110113f7f6c FS: 0000555555b49880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f63ae9fde78 CR3: 000000009873d000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_object_activate+0x2e5/0x470 lib/debugobjects.c:680 debug_timer_activate kernel/time/timer.c:710 [inline] __mod_timer kernel/time/timer.c:1035 [inline] mod_timer+0x452/0xc10 kernel/time/timer.c:1096 sk_reset_timer+0x24/0x60 net/core/sock.c:2821 nr_start_t1timer+0x6e/0xa0 net/netrom/nr_timer.c:52 nr_release+0x1de/0x3e0 net/netrom/af_netrom.c:537 __sock_release+0xce/0x280 net/socket.c:590 sock_close+0x1e/0x30 net/socket.c:1268 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x406901 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 24 1a 00 00 c3 48 83 ec 08 e8 6a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 b3 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffede643710 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000406901 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006dcc30 R08: 0000000120080522 R09: 0000000120080522 R10: 00007ffede643730 R11: 0000000000000293 R12: 00007ffede643760 R13: 0000000000000004 R14: 00000000006dcc3c R15: 0000000000000064 irq event stamp: 0 hardirqs last enabled at (0): [<0000000000000000>] 0x0 hardirqs last disabled at (0): [<ffffffff81437c05>] copy_process+0x1815/0x6b00 kernel/fork.c:1960 softirqs last enabled at (0): [<ffffffff81437cac>] copy_process+0x18bc/0x6b00 kernel/fork.c:1963 softirqs last disabled at (0): [<0000000000000000>] 0x0 ---[ end trace f5b6f61236ba2f96 ]--- ------------[ cut here ]------------