On Fri, May 4, 2018 at 3:07 PM, syzbot <syzbot+7f7b8d424eb621469f0a@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 150426981426 Merge tag 'linux-kselftest-4.17-rc4' of git:/.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=17e4975b800000 > kernel config: https://syzkaller.appspot.com/x/.config?x=5a1dc06635c10d27 > dashboard link: https://syzkaller.appspot.com/bug?extid=7f7b8d424eb621469f0a > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=10652e57800000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11036e47800000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+7f7b8d424eb621469f0a@xxxxxxxxxxxxxxxxxxxxxxxxx This is a repro for: #syz dup: KASAN: use-after-free Read in fuse_kill_sb_blk > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > CPU: 0 PID: 4531 Comm: syz-executor152 Not tainted 4.17.0-rc3+ #32 > ================================================================== > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > BUG: KASAN: use-after-free in __lock_acquire+0x3888/0x5140 > kernel/locking/lockdep.c:3310 > Read of size 8 at addr ffff8801b75554c8 by task syz-executor152/4523 > Call Trace: > > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1b9/0x294 lib/dump_stack.c:113 > fail_dump lib/fault-inject.c:51 [inline] > should_fail.cold.4+0xa/0x1a lib/fault-inject.c:149 > __should_failslab+0x124/0x180 mm/failslab.c:32 > should_failslab+0x9/0x14 mm/slab_common.c:1522 > slab_pre_alloc_hook mm/slab.h:423 [inline] > slab_alloc mm/slab.c:3378 [inline] > __do_kmalloc mm/slab.c:3716 [inline] > __kmalloc_track_caller+0x2c4/0x760 mm/slab.c:3733 > kstrdup+0x39/0x70 mm/util.c:56 > fs_set_subtype fs/namespace.c:2443 [inline] > do_new_mount fs/namespace.c:2521 [inline] > do_mount+0x25e7/0x3070 fs/namespace.c:2848 > ksys_mount+0x12d/0x140 fs/namespace.c:3064 > __do_sys_mount fs/namespace.c:3078 [inline] > __se_sys_mount fs/namespace.c:3075 [inline] > __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 > do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x447cd9 > RSP: 002b:00007fbb431e0828 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 > RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000447cd9 > RDX: 00000000004b08f6 RSI: 0000000020000100 RDI: 00000000004c74a5 > RBP: 000000000000c000 R08: 00007fbb431e0840 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > CPU: 1 PID: 4523 Comm: syz-executor152 Not tainted 4.17.0-rc3+ #32 > 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+0x1b9/0x294 lib/dump_stack.c:113 > print_address_description+0x6c/0x20b mm/kasan/report.c:256 > kasan_report_error mm/kasan/report.c:354 [inline] > kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 > __lock_acquire+0x3888/0x5140 kernel/locking/lockdep.c:3310 > lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 > down_write+0x87/0x120 kernel/locking/rwsem.c:70 > fuse_kill_sb_anon+0x50/0xb0 fs/fuse/inode.c:1200 > deactivate_locked_super+0x97/0x100 fs/super.c:316 > mount_nodev+0xfa/0x110 fs/super.c:1212 > fuse_mount+0x2c/0x40 fs/fuse/inode.c:1192 > mount_fs+0xae/0x328 fs/super.c:1267 > vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037 > vfs_kern_mount fs/namespace.c:1027 [inline] > do_new_mount fs/namespace.c:2518 [inline] > do_mount+0x564/0x3070 fs/namespace.c:2848 > ksys_mount+0x12d/0x140 fs/namespace.c:3064 > __do_sys_mount fs/namespace.c:3078 [inline] > __se_sys_mount fs/namespace.c:3075 [inline] > __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 > do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x447cd9 > RSP: 002b:00007fbb431e0828 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 > RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000447cd9 > RDX: 00000000004b08f6 RSI: 0000000020000100 RDI: 00000000004c74a5 > RBP: 000000000000c000 R08: 00007fbb431e0840 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > > Allocated by task 4523: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 > kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 > kmalloc include/linux/slab.h:512 [inline] > fuse_fill_super+0xc92/0x1e20 fs/fuse/inode.c:1096 > mount_nodev+0x6b/0x110 fs/super.c:1210 > fuse_mount+0x2c/0x40 fs/fuse/inode.c:1192 > mount_fs+0xae/0x328 fs/super.c:1267 > vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037 > vfs_kern_mount fs/namespace.c:1027 [inline] > do_new_mount fs/namespace.c:2518 [inline] > do_mount+0x564/0x3070 fs/namespace.c:2848 > ksys_mount+0x12d/0x140 fs/namespace.c:3064 > __do_sys_mount fs/namespace.c:3078 [inline] > __se_sys_mount fs/namespace.c:3075 [inline] > __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 > do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Freed by task 4312: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 > kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 > __cache_free mm/slab.c:3498 [inline] > kfree+0xd9/0x260 mm/slab.c:3813 > __rcu_reclaim kernel/rcu/rcu.h:173 [inline] > rcu_do_batch kernel/rcu/tree.c:2675 [inline] > invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline] > __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline] > rcu_process_callbacks+0xa69/0x15f0 kernel/rcu/tree.c:2914 > __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 > > The buggy address belongs to the object at ffff8801b7555200 > which belongs to the cache kmalloc-1024 of size 1024 > The buggy address is located 712 bytes inside of > 1024-byte region [ffff8801b7555200, ffff8801b7555600) > The buggy address belongs to the page: > page:ffffea0006dd5500 count:1 mapcount:0 mapping:ffff8801b7554000 index:0x0 > compound_mapcount: 0 > flags: 0x2fffc0000008100(slab|head) > raw: 02fffc0000008100 ffff8801b7554000 0000000000000000 0000000100000007 > raw: ffffea0006dd9020 ffffea0006db0d20 ffff8801da800ac0 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801b7555380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801b7555400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> >> ffff8801b7555480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > ffff8801b7555500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801b7555580: 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@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title > If you want to test a patch for this bug, please reply with: > #syz test: git://repo/address.git branch > and provide the patch inline or as an attachment. > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. > > -- > 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/00000000000004e875056b60fffe%40google.com. > For more options, visit https://groups.google.com/d/optout.
