================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:102 [inline] BUG: KASAN: null-ptr-deref in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline] BUG: KASAN: null-ptr-deref in __refcount_add include/linux/refcount.h:193 [inline] BUG: KASAN: null-ptr-deref in __refcount_inc include/linux/refcount.h:250 [inline] BUG: KASAN: null-ptr-deref in refcount_inc include/linux/refcount.h:267 [inline] BUG: KASAN: null-ptr-deref in get_task_struct include/linux/sched/task.h:110 [inline] BUG: KASAN: null-ptr-deref in kthread_stop+0x108/0x8c0 kernel/kthread.c:705 Write of size 4 at addr 0000000000000028 by task syz-executor664/5963 CPU: 0 PID: 5963 Comm: syz-executor664 Tainted: G W 6.1.122-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_report+0xe4/0x4c0 mm/kasan/report.c:430 kasan_report+0xd4/0x130 mm/kasan/report.c:531 kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189 __kasan_check_write+0x2c/0x3c mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:102 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline] __refcount_add include/linux/refcount.h:193 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] get_task_struct include/linux/sched/task.h:110 [inline] kthread_stop+0x108/0x8c0 kernel/kthread.c:705 f2fs_stop_gc_thread+0x70/0xc0 fs/f2fs/gc.c:209 f2fs_ioc_shutdown fs/f2fs/file.c:2341 [inline] __f2fs_ioctl+0x7cc8/0xb738 fs/f2fs/file.c:4309 f2fs_ioctl+0x130/0x1a0 fs/f2fs/file.c:4390 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 ================================================================== Unable to handle kernel NULL pointer dereference at virtual address 0000000000000028 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=000000010913c000 [0000000000000028] pgd=08000001281ac003, p4d=08000001281ac003, pud=0800000109c44003, pmd=0000000000000000 Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 5963 Comm: syz-executor664 Tainted: G B W 6.1.122-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __lse_atomic_fetch_add_relaxed arch/arm64/include/asm/atomic_lse.h:62 [inline] pc : arch_atomic_fetch_add_relaxed arch/arm64/include/asm/atomic.h:49 [inline] pc : atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:117 [inline] pc : __refcount_add include/linux/refcount.h:193 [inline] pc : __refcount_inc include/linux/refcount.h:250 [inline] pc : refcount_inc include/linux/refcount.h:267 [inline] pc : get_task_struct include/linux/sched/task.h:110 [inline] pc : kthread_stop+0x114/0x8c0 kernel/kthread.c:705 lr : arch_atomic_fetch_add_relaxed arch/arm64/include/asm/atomic.h:49 [inline] lr : atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:117 [inline] lr : __refcount_add include/linux/refcount.h:193 [inline] lr : __refcount_inc include/linux/refcount.h:250 [inline] lr : refcount_inc include/linux/refcount.h:267 [inline] lr : get_task_struct include/linux/sched/task.h:110 [inline] lr : kthread_stop+0x110/0x8c0 kernel/kthread.c:705 sp : ffff800025787700 x29: ffff800025787700 x28: ffff700004af0f2c x27: ffff800025787960 x26: 1fffe0001a6df378 x25: dfff800000000000 x24: 0000000000400140 x23: dfff800000000000 x22: dfff800000000000 x21: 0000000000000028 x20: 0000000000000001 x19: 0000000000000000 x18: 1fffe000367a0176 x17: 0000000000000000 x16: ffff800012330d74 x15: 0000000000000000 x14: 0000000000000000 x13: 205d333639355420 x12: 0000000000000001 x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff80000823620c x8 : 0000000000000001 x7 : 205b5d3038303633 x6 : ffff8000083445a4 x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff8000081a9738 x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: arch_atomic_fetch_add_relaxed arch/arm64/include/asm/atomic.h:49 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:117 [inline] __refcount_add include/linux/refcount.h:193 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] get_task_struct include/linux/sched/task.h:110 [inline] kthread_stop+0x114/0x8c0 kernel/kthread.c:705 f2fs_stop_gc_thread+0x70/0xc0 fs/f2fs/gc.c:209 f2fs_ioc_shutdown fs/f2fs/file.c:2341 [inline] __f2fs_ioctl+0x7cc8/0xb738 fs/f2fs/file.c:4309 f2fs_ioctl+0x130/0x1a0 fs/f2fs/file.c:4390 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Code: 941d0188 d503201f 940af3dc 52800028 (b82802b4) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 941d0188 bl 0x740620 4: d503201f nop 8: 940af3dc bl 0x2bcf78 c: 52800028 mov w8, #0x1 // #1 * 10: b82802b4 ldadd w8, w20, [x21] <-- trapping instruction