On Thu, Oct 13, 2022 at 5:18 PM syzbot wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: bbed346d5a96 Merge branch 'for-next/core' into for-kernelci > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=161c8578880000 > kernel config: https://syzkaller.appspot.com/x/.config?x=3a4a45d2d827c1e > dashboard link: https://syzkaller.appspot.com/bug?extid=e67c6877ee7e6e68c45a > compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 > userspace arch: arm64 > > Unfortunately, I don't have any reproducer for this issue yet. > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/e8e91bc79312/disk-bbed346d.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/c1cb3fb3b77e/vmlinux-bbed346d.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+e67c6877ee7e6e68c45a@xxxxxxxxxxxxxxxxxxxxxxxxx > > ------------[ cut here ]------------ > ODEBUG: free active (active state 0) object type: timer_list hint: br_multicast_group_expired+0x0/0x230 net/bridge/br_multicast.c:606 > WARNING: CPU: 1 PID: 8079 at lib/debugobjects.c:505 debug_print_object lib/debugobjects.c:502 [inline] > WARNING: CPU: 1 PID: 8079 at lib/debugobjects.c:505 __debug_check_no_obj_freed lib/debugobjects.c:989 [inline] > WARNING: CPU: 1 PID: 8079 at lib/debugobjects.c:505 debug_check_no_obj_freed+0x214/0x2b0 lib/debugobjects.c:1020 > Modules linked in: > CPU: 1 PID: 8079 Comm: syz-executor.4 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 > pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : debug_print_object lib/debugobjects.c:502 [inline] > pc : __debug_check_no_obj_freed lib/debugobjects.c:989 [inline] > pc : debug_check_no_obj_freed+0x214/0x2b0 lib/debugobjects.c:1020 > lr : debug_print_object lib/debugobjects.c:502 [inline] > lr : __debug_check_no_obj_freed lib/debugobjects.c:989 [inline] > lr : debug_check_no_obj_freed+0x214/0x2b0 lib/debugobjects.c:1020 > sp : ffff80001488b990 > x29: ffff80001488b9b0 x28: ffff000134488000 x27: ffff000134489000 > x26: ffff0001362a1398 x25: ffff000121ada0f0 x24: ffff80000bfff5b8 > x23: ffff000134488f40 x22: ffff80000bfff5b8 x21: 0000000000000001 > x20: dead000000000100 x19: ffff000134488f00 x18: 000000000000010e > x17: 0000000000000000 x16: ffff80000db49158 x15: ffff0000facdb500 > x14: 0000000000000000 x13: 00000000ffffffff x12: 0000000000040000 > x11: 0000000000006464 x10: ffff80001f2be000 x9 : 49f3c7340dde9a00 > x8 : 49f3c7340dde9a00 x7 : ffff800008161d1c x6 : 0000000000000000 > x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 > x2 : 0000000000000007 x1 : 0000000100000000 x0 : 0000000000000067 > Call trace: > debug_print_object lib/debugobjects.c:502 [inline] > __debug_check_no_obj_freed lib/debugobjects.c:989 [inline] > debug_check_no_obj_freed+0x214/0x2b0 lib/debugobjects.c:1020 > slab_free_hook mm/slub.c:1734 [inline] > slab_free_freelist_hook mm/slub.c:1785 [inline] > slab_free mm/slub.c:3539 [inline] > kfree+0x14c/0x348 mm/slub.c:4567 > nilfs_mdt_destroy+0x2c/0x3c fs/nilfs2/mdt.c:498 > nilfs_free_inode+0x2c/0x54 fs/nilfs2/super.c:168 > i_callback fs/inode.c:249 [inline] > alloc_inode+0xdc/0x104 fs/inode.c:274 > new_inode_pseudo fs/inode.c:1019 [inline] > new_inode+0x2c/0xc0 fs/inode.c:1047 > nilfs_new_inode+0x48/0x378 fs/nilfs2/inode.c:334 > nilfs_mknod+0x7c/0x170 fs/nilfs2/namei.c:113 > vfs_mknod+0x2e8/0x318 fs/namei.c:3892 > unix_bind_bsd+0x138/0x320 net/unix/af_unix.c:1192 > unix_bind+0xd4/0x10c net/unix/af_unix.c:1283 > __sys_bind+0x148/0x1b0 net/socket.c:1776 > __do_sys_bind net/socket.c:1787 [inline] > __se_sys_bind net/socket.c:1785 [inline] > __arm64_sys_bind+0x28/0x3c net/socket.c:1785 > __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] > invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] > el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 > do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 > el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 > el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 > el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 > irq event stamp: 3716 > hardirqs last enabled at (3715): [<ffff800008161dac>] raw_spin_rq_unlock_irq kernel/sched/sched.h:1367 [inline] > hardirqs last enabled at (3715): [<ffff800008161dac>] finish_lock_switch+0x94/0xe8 kernel/sched/core.c:4942 > hardirqs last disabled at (3716): [<ffff80000bfb5fbc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:404 > softirqs last enabled at (3520): [<ffff80000801c33c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 > softirqs last disabled at (3518): [<ffff80000801c308>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 > ---[ end trace 0000000000000000 ]--- > > > --- > This report 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 issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. #syz dup: KASAN: use-after-free Read in nilfs_mdt_destroy According to the stack trace, the abnormal condition starts with nilfs_mdt_destroy(), which is triggered from the error path in alloc_inode(). This is the same issue as the above report. The bugfix for this is already merged in the mainline, but the tested point (6.0.0-rc7) is before that. Ryusuke Konishi
