general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 0 PID: 5070 Comm: syz-fuzzer Not tainted 6.2.0-rc7-next-20230208-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 RIP: 0010:collect_signal+0x86/0x630 kernel/signal.c:578 Code: 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 af 04 00 00 48 8b 1b 49 39 de 74 43 e8 65 c7 34 00 48 8d 7b 18 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 74 08 3c 03 0f 8e 93 04 00 00 44 8b 7b 18 89 RSP: 0018:ffffc90003acfc48 EFLAGS: 00010006 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801e618000 RSI: ffffffff814fa67b RDI: 0000000000000018 RBP: 0000000000000017 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000017 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88801e618890 R15: 0000000000000000 FS: 000000c000050490(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efe726d56be CR3: 00000000283b6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __dequeue_signal kernel/signal.c:619 [inline] dequeue_signal+0x22e/0x650 kernel/signal.c:639 get_signal+0x57e/0x25b0 kernel/signal.c:2739 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0033:0x500da4 Code: 00 00 eb 0c 48 8d ba e0 10 00 00 e8 96 4a f6 ff 48 8b 6c 24 70 48 83 c4 78 c3 49 39 c8 0f 8d a1 00 00 00 48 8b b0 98 10 00 00 <4c> 8b 90 88 10 00 00 48 39 ce 0f 82 dc 01 00 00 49 39 c8 0f 87 cb RSP: 002b:000000c007d4ed90 EFLAGS: 00000293 RAX: 000000c003b88c00 RBX: 0000000000000020 RCX: 0000000000001253 RDX: 0000000000001151 RSI: 0000000000008000 RDI: 000000c006bc9170 RBP: 000000c007d4ee00 R08: 0000000000001190 R09: 0000000000001150 R10: 000000c006bc8000 R11: 0000000000001253 R12: 0000000000001150 R13: 0000000000001170 R14: 000000c0000001a0 R15: 0000000000000010 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:collect_signal+0x86/0x630 kernel/signal.c:578 Code: 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 af 04 00 00 48 8b 1b 49 39 de 74 43 e8 65 c7 34 00 48 8d 7b 18 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 74 08 3c 03 0f 8e 93 04 00 00 44 8b 7b 18 89 RSP: 0018:ffffc90003acfc48 EFLAGS: 00010006 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801e618000 RSI: ffffffff814fa67b RDI: 0000000000000018 RBP: 0000000000000017 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000017 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88801e618890 R15: 0000000000000000 FS: 000000c000050490(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efe726d56be CR3: 00000000283b6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 89 d8 mov %rbx,%rax 3: 48 c1 e8 03 shr $0x3,%rax 7: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) c: 0f 85 af 04 00 00 jne 0x4c1 12: 48 8b 1b mov (%rbx),%rbx 15: 49 39 de cmp %rbx,%r14 18: 74 43 je 0x5d 1a: e8 65 c7 34 00 callq 0x34c784 1f: 48 8d 7b 18 lea 0x18(%rbx),%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 74 08 je 0x3b 33: 3c 03 cmp $0x3,%al 35: 0f 8e 93 04 00 00 jle 0x4ce 3b: 44 8b 7b 18 mov 0x18(%rbx),%r15d 3f: 89 .byte 0x89