On Sun, Oct 21, 2018 at 11:40 AM syzbot <syzbot+f25db12f1fd508824eac@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: 270b77a0f30e Merge tag 'drm-fixes-2018-10-20-1' of git://a.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=152bb709400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=b3f55cb3dfcc6c33 > dashboard link: https://syzkaller.appspot.com/bug?extid=f25db12f1fd508824eac > compiler: gcc (GCC) 8.0.1 20180413 (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+f25db12f1fd508824eac@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: use-after-free in __lock_acquire+0x37c2/0x4ec0 > kernel/locking/lockdep.c:3290 > Read of size 8 at addr ffff8801d28a81a8 by task syz-executor4/12225 This seems to have been fixed by: #syz fix: ucma: fix a use-after-free in ucma_resolve_ip() So let's close the bug. Pile of neglected bug reports is not too useful. > CPU: 1 PID: 12225 Comm: syz-executor4 Not tainted 4.19.0-rc8+ #72 > 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+0x1c4/0x2b4 lib/dump_stack.c:113 > print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 > kasan_report_error mm/kasan/report.c:354 [inline] > kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 > __lock_acquire+0x37c2/0x4ec0 kernel/locking/lockdep.c:3290 > lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3900 > __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] > _raw_spin_lock_irq+0x61/0x80 kernel/locking/spinlock.c:160 > spin_lock_irq include/linux/spinlock.h:354 [inline] > do_wait_for_common kernel/sched/completion.c:84 [inline] > __wait_for_common kernel/sched/completion.c:104 [inline] > wait_for_common kernel/sched/completion.c:115 [inline] > wait_for_completion+0x436/0x8a0 kernel/sched/completion.c:136 > ucma_destroy_id+0x38a/0x550 drivers/infiniband/core/ucma.c:637 > ucma_write+0x365/0x460 drivers/infiniband/core/ucma.c:1689 > __vfs_write+0x119/0x9f0 fs/read_write.c:485 > vfs_write+0x1fc/0x560 fs/read_write.c:549 > ksys_write+0x101/0x260 fs/read_write.c:598 > __do_sys_write fs/read_write.c:610 [inline] > __se_sys_write fs/read_write.c:607 [inline] > __x64_sys_write+0x73/0xb0 fs/read_write.c:607 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x457569 > Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fe8a3f8ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 > RDX: 0000000000000018 RSI: 0000000020000280 RDI: 0000000000000005 > RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8a3f8f6d4 > R13: 00000000004cb4f8 R14: 00000000004d8b68 R15: 00000000ffffffff > > Allocated by task 12210: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 > kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 > kmalloc include/linux/slab.h:513 [inline] > kzalloc include/linux/slab.h:707 [inline] > ucma_alloc_ctx+0xce/0x690 drivers/infiniband/core/ucma.c:209 > ucma_create_id+0x27d/0x990 drivers/infiniband/core/ucma.c:500 > ucma_write+0x365/0x460 drivers/infiniband/core/ucma.c:1689 > __vfs_write+0x119/0x9f0 fs/read_write.c:485 > vfs_write+0x1fc/0x560 fs/read_write.c:549 > ksys_write+0x101/0x260 fs/read_write.c:598 > __do_sys_write fs/read_write.c:610 [inline] > __se_sys_write fs/read_write.c:607 [inline] > __x64_sys_write+0x73/0xb0 fs/read_write.c:607 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Freed by task 12210: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 > kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 > __cache_free mm/slab.c:3498 [inline] > kfree+0xcf/0x230 mm/slab.c:3813 > ucma_free_ctx+0x9e6/0xdb0 drivers/infiniband/core/ucma.c:599 > ucma_close+0x121/0x310 drivers/infiniband/core/ucma.c:1775 > __fput+0x385/0xa30 fs/file_table.c:278 > ____fput+0x15/0x20 fs/file_table.c:309 > task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 > get_signal+0x155e/0x1980 kernel/signal.c:2343 > do_signal+0x9c/0x21e0 arch/x86/kernel/signal.c:816 > exit_to_usermode_loop+0x2e5/0x380 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+0x6be/0x820 arch/x86/entry/common.c:293 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > The buggy address belongs to the object at ffff8801d28a8180 > which belongs to the cache kmalloc-256 of size 256 > The buggy address is located 40 bytes inside of > 256-byte region [ffff8801d28a8180, ffff8801d28a8280) > The buggy address belongs to the page: > page:ffffea00074a2a00 count:1 mapcount:0 mapping:ffff8801da8007c0 index:0x0 > flags: 0x2fffc0000000100(slab) > raw: 02fffc0000000100 ffffea000760b108 ffffea0007491148 ffff8801da8007c0 > raw: 0000000000000000 ffff8801d28a8040 000000010000000c 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801d28a8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff8801d28a8100: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ffff8801d28a8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8801d28a8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801d28a8280: fc fc fc fc fc fc fc fc 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@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/000000000000c57a190578b9eb98%40google.com. > For more options, visit https://groups.google.com/d/optout.
