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=14e5373a880000 kernel config: https://syzkaller.appspot.com/x/.config?x=3a4a45d2d827c1e dashboard link: https://syzkaller.appspot.com/bug?extid=55b93dba2f5f385ebe4d 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+55b93dba2f5f385ebe4d@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 1 PID: 12653 at kernel/locking/mutex.c:582 __mutex_lock_common+0x4c4/0xca8 kernel/locking/mutex.c:582 Modules linked in: CPU: 1 PID: 12653 Comm: syz-executor.1 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 : __mutex_lock_common+0x4c4/0xca8 kernel/locking/mutex.c:582 lr : __mutex_lock_common+0x4c4/0xca8 kernel/locking/mutex.c:582 sp : ffff800013983aa0 x29: ffff800013983b10 x28: ffff80000ee2b000 x27: 00000000ffffff00 x26: 0000000000000000 x25: 0000000000000046 x24: 0000000000000002 x23: ffff80000878a408 x22: 0000000000000000 x21: 0000000000000000 x20: 0000000000000000 x19: ffff000100e2d028 x18: 00000000000000c0 x17: ffff80000dd0b198 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000012 x12: 0000000000040000 x11: 00000000000044aa x10: ffff80001f44d000 x9 : 7d4b49b29f0bd400 x8 : 7d4b49b29f0bd400 x7 : 4e5241575f534b43 x6 : ffff80000819545c x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000100000000 x0 : 0000000000000028 Call trace: __mutex_lock_common+0x4c4/0xca8 kernel/locking/mutex.c:582 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 reiserfs_write_lock+0x3c/0x64 fs/reiserfs/lock.c:27 reiserfs_setattr+0x298/0x7f4 fs/reiserfs/inode.c:3284 notify_change+0x758/0x7f0 fs/attr.c:420 chown_common+0x29c/0x388 fs/open.c:736 do_fchownat+0xec/0x1a0 fs/open.c:767 __do_sys_fchownat fs/open.c:782 [inline] __se_sys_fchownat fs/open.c:779 [inline] __arm64_sys_fchownat+0x30/0x44 fs/open.c:779 __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: 1633 hardirqs last enabled at (1633): [<ffff800008223334>] seqcount_lockdep_reader_access include/linux/seqlock.h:104 [inline] hardirqs last enabled at (1633): [<ffff800008223334>] ktime_get_coarse_real_ts64+0xfc/0x1bc kernel/time/timekeeping.c:2261 hardirqs last disabled at (1632): [<ffff8000082232c4>] seqcount_lockdep_reader_access include/linux/seqlock.h:101 [inline] hardirqs last disabled at (1632): [<ffff8000082232c4>] ktime_get_coarse_real_ts64+0x8c/0x1bc kernel/time/timekeeping.c:2261 softirqs last enabled at (1598): [<ffff80000801c33c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (1596): [<ffff80000801c308>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- Unable to handle kernel NULL pointer dereference at virtual address 000000000000003c Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=000000013197f000 [000000000000003c] pgd=0800000140f65003, p4d=0800000140f65003, pud=0800000140ddf003, pmd=0000000000000000 Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 12653 Comm: syz-executor.1 Tainted: G W 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 : owner_on_cpu include/linux/sched.h:2269 [inline] pc : mutex_can_spin_on_owner kernel/locking/mutex.c:409 [inline] pc : mutex_optimistic_spin+0x1c8/0x254 kernel/locking/mutex.c:452 lr : __mutex_lock_common+0x1b4/0xca8 kernel/locking/mutex.c:607 sp : ffff800013983a40 x29: ffff800013983a50 x28: ffff80000ee2b000 x27: ffff80000cb4f733 x26: 0000000000000000 x25: 0000000000000046 x24: ffff000100e2d090 x23: ffff80000878a408 x22: ffff80000d30c000 x21: 0000000000000000 x20: 0000000000000000 x19: ffff000100e2d028 x18: 00000000000000c0 x17: ffff80000dd0b198 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000012 x12: 0000000000040000 x11: 00000000000044aa x10: ffff80000d30c000 x9 : 0000000000000003 x8 : 0000000000000008 x7 : 4e5241575f534b43 x6 : ffff80000878a408 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000100e2d028 Call trace: mutex_can_spin_on_owner kernel/locking/mutex.c:408 [inline] mutex_optimistic_spin+0x1c8/0x254 kernel/locking/mutex.c:452 __mutex_lock_common+0x1b4/0xca8 kernel/locking/mutex.c:607 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 reiserfs_write_lock+0x3c/0x64 fs/reiserfs/lock.c:27 reiserfs_setattr+0x298/0x7f4 fs/reiserfs/inode.c:3284 notify_change+0x758/0x7f0 fs/attr.c:420 chown_common+0x29c/0x388 fs/open.c:736 do_fchownat+0xec/0x1a0 fs/open.c:767 __do_sys_fchownat fs/open.c:782 [inline] __se_sys_fchownat fs/open.c:779 [inline] __arm64_sys_fchownat+0x30/0x44 fs/open.c:779 __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 Code: 37080148 f9400268 f27df108 54000080 (b9403509) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 37080148 tbnz w8, #1, 0x28 4: f9400268 ldr x8, [x19] 8: f27df108 ands x8, x8, #0xfffffffffffffff8 c: 54000080 b.eq 0x1c // b.none * 10: b9403509 ldr w9, [x8, #52] <-- trapping instruction --- This report is generated by a bot. 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