On Mon, Oct 17, 2022 at 4:53 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=14b7bfa4880000 > kernel config: https://syzkaller.appspot.com/x/.config?x=3a4a45d2d827c1e > dashboard link: https://syzkaller.appspot.com/bug?extid=5f89bb8d098de14e095a > 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 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16dbead6880000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=105d329a880000 > > 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 > mounted in repro: https://storage.googleapis.com/syzbot-assets/79de466a501c/mount_0.gz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+5f89bb8d098de14e095a@xxxxxxxxxxxxxxxxxxxxxxxxx > > BUG: spinlock bad magic on CPU#1, syz-executor283/3079 > lock: lock_classes+0x4aac0/0x180000, .magic: ffff8000, .owner: /235063856, .owner_cpu: 242347152 > CPU: 1 PID: 3079 Comm: syz-executor283 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 > Call trace: > dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156 > show_stack+0x2c/0x54 arch/arm64/kernel/stacktrace.c:163 > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106 > dump_stack+0x1c/0x58 lib/dump_stack.c:113 > spin_dump kernel/locking/spinlock_debug.c:69 [inline] > spin_bug+0xa8/0xec kernel/locking/spinlock_debug.c:77 > debug_spin_lock_before kernel/locking/spinlock_debug.c:85 [inline] > do_raw_spin_lock+0xb0/0x110 kernel/locking/spinlock_debug.c:114 > __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] > _raw_spin_lock+0x5c/0x6c kernel/locking/spinlock.c:154 > spin_lock include/linux/spinlock.h:349 [inline] > nilfs_palloc_clear_cache fs/nilfs2/alloc.c:848 [inline] > nilfs_palloc_destroy_cache+0x2c/0xb8 fs/nilfs2/alloc.c:860 > nilfs_mdt_clear+0x34/0x70 fs/nilfs2/mdt.c:478 > nilfs_clear_inode+0x64/0x140 fs/nilfs2/inode.c:886 > nilfs_evict_inode+0x68/0x1cc fs/nilfs2/inode.c:908 > evict+0xec/0x334 fs/inode.c:665 > iput_final fs/inode.c:1748 [inline] > iput+0x2c4/0x324 fs/inode.c:1774 > nilfs_put_super+0x6c/0x9c fs/nilfs2/super.c:476 > generic_shutdown_super+0x8c/0x190 fs/super.c:491 > kill_block_super+0x30/0x78 fs/super.c:1427 > deactivate_locked_super+0x70/0xe8 fs/super.c:332 > deactivate_super+0xd0/0xd4 fs/super.c:363 > cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 > __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 > task_work_run+0xc4/0x14c kernel/task_work.c:177 > resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] > do_notify_resume+0x174/0x1f0 arch/arm64/kernel/signal.c:1127 > prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] > exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] > el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:637 > el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 > el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 > Unable to handle kernel paging request at virtual address ffff80000d272a70 > Mem abort info: > ESR = 0x0000000096000047 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x07: level 3 translation fault > Data abort info: > ISV = 0, ISS = 0x00000047 > CM = 0, WnR = 1 > swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000001c566b000 > [ffff80000d272a70] pgd=100000023ffff003, p4d=100000023ffff003, pud=100000023fffe003, pmd=100000023fffa003, pte=0000000000000000 > Internal error: Oops: 0000000096000047 [#1] PREEMPT SMP > Modules linked in: > CPU: 1 PID: 3079 Comm: syz-executor283 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: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : queued_spin_lock_slowpath+0x198/0x380 kernel/locking/qspinlock.c:474 > lr : queued_spin_lock_slowpath+0x114/0x380 kernel/locking/qspinlock.c:405 > sp : ffff800010fe3a70 > x29: ffff800010fe3a70 x28: ffff0000c02f4f80 x27: 0000000000000000 > x26: ffff80000d30cf28 x25: 0000000000000000 x24: ffff0001fefefa40 > x23: 0000000000000000 x22: ffff80000d30cf28 x21: ffff80000d272a40 > x20: 0000000000000001 x19: ffff80000db93c18 x18: 0000000000000260 > x17: 6e69676e45206574 x16: 0000000000000002 x15: 0000000000000000 > x14: 0000000000000000 x13: 0000000000000db7 x12: 0000000000000000 > x11: ffff80000d272a70 x10: 0000000000080000 x9 : ffff0001fefefa48 > x8 : ffff0001fefefa40 x7 : 205b5d3838383531 x6 : ffff80000819545c > x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 > x2 : 0000000000000001 x1 : ffff80000ce26a9f x0 : 0000000000000001 > Call trace: > decode_tail kernel/locking/qspinlock.c:131 [inline] > queued_spin_lock_slowpath+0x198/0x380 kernel/locking/qspinlock.c:471 > queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] > do_raw_spin_lock+0x10c/0x110 kernel/locking/spinlock_debug.c:115 > __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] > _raw_spin_lock+0x5c/0x6c kernel/locking/spinlock.c:154 > spin_lock include/linux/spinlock.h:349 [inline] > nilfs_palloc_clear_cache fs/nilfs2/alloc.c:848 [inline] > nilfs_palloc_destroy_cache+0x2c/0xb8 fs/nilfs2/alloc.c:860 > nilfs_mdt_clear+0x34/0x70 fs/nilfs2/mdt.c:478 > nilfs_clear_inode+0x64/0x140 fs/nilfs2/inode.c:886 > nilfs_evict_inode+0x68/0x1cc fs/nilfs2/inode.c:908 > evict+0xec/0x334 fs/inode.c:665 > iput_final fs/inode.c:1748 [inline] > iput+0x2c4/0x324 fs/inode.c:1774 > nilfs_put_super+0x6c/0x9c fs/nilfs2/super.c:476 > generic_shutdown_super+0x8c/0x190 fs/super.c:491 > kill_block_super+0x30/0x78 fs/super.c:1427 > deactivate_locked_super+0x70/0xe8 fs/super.c:332 > deactivate_super+0xd0/0xd4 fs/super.c:363 > cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 > __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 > task_work_run+0xc4/0x14c kernel/task_work.c:177 > resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] > do_notify_resume+0x174/0x1f0 arch/arm64/kernel/signal.c:1127 > prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] > exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] > el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:637 > el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 > el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 > Code: 8b2c4ecc f85f818c 1200056b 8b2b52ab (f82b6988) > ---[ end trace 0000000000000000 ]--- > ---------------- > Code disassembly (best guess): > 0: 8b2c4ecc add x12, x22, w12, uxtw #3 > 4: f85f818c ldur x12, [x12, #-8] > 8: 1200056b and w11, w11, #0x3 > c: 8b2b52ab add x11, x21, w11, uxtw #4 > * 10: f82b6988 str x8, [x12, x11] <-- trapping instruction > > > --- > 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. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches This is the same UAF bug as below: #syz dup: BUG: unable to handle kernel paging request in kernfs_put_active The bugfix for this is the patch titled "fs: fix UAF/GPF bug in nilfs_mdt_destroy", which is already merged in the mainline. I confirmed that the above patch suppresses the bug by using the C-reproducer. Ryusuke Konishi
