================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: null-ptr-deref in test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:55 [inline] BUG: KASAN: null-ptr-deref in trylock_buffer include/linux/buffer_head.h:395 [inline] BUG: KASAN: null-ptr-deref in lock_buffer include/linux/buffer_head.h:401 [inline] BUG: KASAN: null-ptr-deref in udf_getblk fs/udf/inode.c:383 [inline] BUG: KASAN: null-ptr-deref in udf_bread+0x234/0x5b0 fs/udf/inode.c:1111 Write of size 8 at addr 0000000000000000 by task syz.3.135/4743 CPU: 1 PID: 4743 Comm: syz.3.135 Not tainted 5.15.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 __kasan_report mm/kasan/report.c:438 [inline] kasan_report+0x168/0x1e4 mm/kasan/report.c:451 kasan_check_range+0x274/0x2b4 mm/kasan/generic.c:189 __kasan_check_write+0x44/0x54 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:55 [inline] trylock_buffer include/linux/buffer_head.h:395 [inline] lock_buffer include/linux/buffer_head.h:401 [inline] udf_getblk fs/udf/inode.c:383 [inline] udf_bread+0x234/0x5b0 fs/udf/inode.c:1111 udf_fiiter_append_blk+0x310/0x7b8 fs/udf/directory.c:463 udf_fiiter_add_entry+0xff8/0x1934 fs/udf/namei.c:292 udf_mkdir+0x118/0x5a0 fs/udf/namei.c:436 vfs_mkdir+0x334/0x4e4 fs/namei.c:4065 do_mkdirat+0x20c/0x610 fs/namei.c:4090 __do_sys_mkdirat fs/namei.c:4105 [inline] __se_sys_mkdirat fs/namei.c:4103 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 ================================================================== Unable to handle kernel paging request at virtual address dfff800000000000 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 [dfff800000000000] address between user and kernel address ranges Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 4743 Comm: syz.3.135 Tainted: G B 5.15.176-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 : arch_test_and_set_bit_lock include/asm-generic/bitops/lock.h:25 [inline] pc : test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:56 [inline] pc : trylock_buffer include/linux/buffer_head.h:395 [inline] pc : lock_buffer include/linux/buffer_head.h:401 [inline] pc : udf_getblk fs/udf/inode.c:383 [inline] pc : udf_bread+0x238/0x5b0 fs/udf/inode.c:1111 lr : instrument_atomic_read_write include/linux/instrumented.h:101 [inline] lr : test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:55 [inline] lr : trylock_buffer include/linux/buffer_head.h:395 [inline] lr : lock_buffer include/linux/buffer_head.h:401 [inline] lr : udf_getblk fs/udf/inode.c:383 [inline] lr : udf_bread+0x234/0x5b0 fs/udf/inode.c:1111 sp : ffff8000211b72e0 x29: ffff8000211b7460 x28: ffff8000211b7300 x27: dfff800000000000 x26: ffff700004236e60 x25: 0000000000000000 x24: 1ffff00004236ea4 x23: 0000000000000030 x22: 0000000000000000 x21: ffff8000211b7410 x20: ffff0000e81a1490 x19: ffff8000211b7520 x18: 1fffe0003683318e x17: 1fffe0003683318e x16: ffff800011b4b268 x15: ffff800014bffac0 x14: ffff0001b4198c80 x13: ffff0001b4198c7c x12: 0000000000080000 x11: 000000000007ffff x10: ffff8000235fb000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff80000826abdc x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80000819c3ec x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000000 Call trace: arch_test_and_set_bit_lock include/asm-generic/bitops/lock.h:25 [inline] test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:56 [inline] trylock_buffer include/linux/buffer_head.h:395 [inline] lock_buffer include/linux/buffer_head.h:401 [inline] udf_getblk fs/udf/inode.c:383 [inline] udf_bread+0x238/0x5b0 fs/udf/inode.c:1111 udf_fiiter_append_blk+0x310/0x7b8 fs/udf/directory.c:463 udf_fiiter_add_entry+0xff8/0x1934 fs/udf/namei.c:292 udf_mkdir+0x118/0x5a0 fs/udf/namei.c:436 vfs_mkdir+0x334/0x4e4 fs/namei.c:4065 do_mkdirat+0x20c/0x610 fs/namei.c:4090 __do_sys_mkdirat fs/namei.c:4105 [inline] __se_sys_mkdirat fs/namei.c:4103 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Code: aa1603e0 52800101 97bfcc64 d343fed9 (387b6b28) ---[ end trace a0de10ca9940ce8f ]--- ---------------- Code disassembly (best guess): 0: aa1603e0 mov x0, x22 4: 52800101 mov w1, #0x8 // #8 8: 97bfcc64 bl 0xfffffffffeff3198 c: d343fed9 lsr x25, x22, #3 * 10: 387b6b28 ldrb w8, [x25, x27] <-- trapping instruction