general protection fault, probably for non-canonical address 0xdffffc000000003d: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000001e8-0x00000000000001ef] CPU: 1 PID: 31177 Comm: syz-executor.5 Not tainted 6.3.0-syzkaller-13390-g2e1e1337881b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__lock_acquire+0x69/0x2000 kernel/locking/lockdep.c:4942 Code: df 0f b6 04 30 84 c0 0f 85 5a 16 00 00 83 3d 01 f0 ea 0c 00 0f 84 02 11 00 00 83 3d 90 48 74 0b 00 74 2b 4c 89 f0 48 c1 e8 03 <80> 3c 30 00 74 12 4c 89 f7 e8 59 32 78 00 48 be 00 00 00 00 00 fc RSP: 0018:ffffc9000379ef58 EFLAGS: 00010002 RAX: 000000000000003d RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 00000000000001e8 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: 0000000000000000 R14: 00000000000001e8 R15: ffff8880207f1dc0 FS: 00007f47f7e44700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f47f7e02718 CR3: 0000000050da9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] mark_buffer_dirty_inode+0x12a/0x300 fs/buffer.c:624 fat12_ent_put+0x1af/0x2d0 fs/fat/fatent.c:173 fat_alloc_clusters+0x591/0x11a0 fs/fat/fatent.c:503 fat_add_cluster fs/fat/inode.c:108 [inline] __fat_get_block fs/fat/inode.c:155 [inline] fat_get_block+0x4c4/0xcf0 fs/fat/inode.c:190 __block_write_begin_int+0x548/0x1a50 fs/buffer.c:2064 __block_write_begin fs/buffer.c:2114 [inline] block_write_begin+0x9c/0x1f0 fs/buffer.c:2175 cont_write_begin+0x643/0x880 fs/buffer.c:2534 fat_write_begin+0x98/0x160 fs/fat/inode.c:230 cont_expand_zero fs/buffer.c:2494 [inline] cont_write_begin+0x6e5/0x880 fs/buffer.c:2524 fat_write_begin+0x98/0x160 fs/fat/inode.c:230 generic_cont_expand_simple+0x18b/0x2a0 fs/buffer.c:2425 fat_cont_expand+0x60/0x1d0 fs/fat/file.c:223 fat_setattr+0x40b/0x1020 fs/fat/file.c:513 notify_change+0xc8b/0xf40 fs/attr.c:483 do_truncate+0x220/0x300 fs/open.c:66 do_sys_ftruncate+0x2e4/0x380 fs/open.c:194 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f47f708c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f47f7e44168 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007f47f71abf80 RCX: 00007f47f708c169 RDX: 0000000000000000 RSI: 00000000000007fb RDI: 0000000000000004 RBP: 00007f47f70e7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc9e20381f R14: 00007f47f7e44300 R15: 0000000000022000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__lock_acquire+0x69/0x2000 kernel/locking/lockdep.c:4942 Code: df 0f b6 04 30 84 c0 0f 85 5a 16 00 00 83 3d 01 f0 ea 0c 00 0f 84 02 11 00 00 83 3d 90 48 74 0b 00 74 2b 4c 89 f0 48 c1 e8 03 <80> 3c 30 00 74 12 4c 89 f7 e8 59 32 78 00 48 be 00 00 00 00 00 fc RSP: 0018:ffffc9000379ef58 EFLAGS: 00010002 RAX: 000000000000003d RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 00000000000001e8 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: 0000000000000000 R14: 00000000000001e8 R15: ffff8880207f1dc0 FS: 00007f47f7e44700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f47f7e02718 CR3: 0000000050da9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: df 0f fisttps (%rdi) 2: b6 04 mov $0x4,%dh 4: 30 84 c0 0f 85 5a 16 xor %al,0x165a850f(%rax,%rax,8) b: 00 00 add %al,(%rax) d: 83 3d 01 f0 ea 0c 00 cmpl $0x0,0xceaf001(%rip) # 0xceaf015 14: 0f 84 02 11 00 00 je 0x111c 1a: 83 3d 90 48 74 0b 00 cmpl $0x0,0xb744890(%rip) # 0xb7448b1 21: 74 2b je 0x4e 23: 4c 89 f0 mov %r14,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 30 00 cmpb $0x0,(%rax,%rsi,1) <-- trapping instruction 2e: 74 12 je 0x42 30: 4c 89 f7 mov %r14,%rdi 33: e8 59 32 78 00 callq 0x783291 38: 48 rex.W 39: be 00 00 00 00 mov $0x0,%esi 3e: 00 fc add %bh,%ah