Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 26873 Comm: syz.0.7022 Not tainted 6.16.0-rc3-next-20250623-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pidfs_free_pid+0xaf/0x140 fs/pidfs.c:162
Code: f0 ff ff 73 e4 43 80 3c 3c 00 74 08 4c 89 f7 e8 a7 1b de ff 49 83 3e 00 0f 85 84 00 00 00 e8 08 f2 79 ff 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 82 1b de ff 4c 8b 33 4d 85 f6 74
RSP: 0018:ffffc90000007b90 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880263e0000
RDX: 0000000000000100 RSI: 0000000000000001 RDI: ffff8880a93df570
RBP: 0000000000000001 R08: ffff8880a93df503 R09: 1ffff1101527bea0
R10: dffffc0000000000 R11: ffffed101527bea1 R12: 1ffff1101527bead
R13: ffffffff81a83684 R14: ffff8880a93df568 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8719df3c60 CR3: 0000000064cb0000 CR4: 00000000003526f0
DR0: 0000000000000007 DR1: 0000000000000001 DR2: 0000000000000007
DR3: 00000000000002d5 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
put_pid+0x9c/0x130 kernel/pid.c:103
rcu_do_batch kernel/rcu/tree.c:2582 [inline]
rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2838
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x18/0x90 kernel/kcov.c:321
Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 b0 9f 92 65 8b 15 58 de df 10 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 3c 16 00 00
RSP: 0018:ffffc9000bbd7360 EFLAGS: 00000246
RAX: ffffffff8209c6c6 RBX: ffffc9000bbd7860 RCX: ffff8880263e0000
RDX: 0000000080000001 RSI: 80000000276e9007 RDI: 0000000000000000
RBP: ffffc9000bbd7650 R08: ffffea0000a1a2b3 R09: 1ffffd4000143456
R10: dffffc0000000000 R11: fffff94000143457 R12: ffff88807d8b73c0
R13: dffffc0000000000 R14: 00007f16a6dcf000 R15: 80000000276e9007
__pte_needs_invert arch/x86/include/asm/pgtable-invert.h:18 [inline]
protnone_mask arch/x86/include/asm/pgtable-invert.h:24 [inline]
pte_pfn arch/x86/include/asm/pgtable.h:266 [inline]
vm_normal_page+0x26/0x230 mm/memory.c:608
zap_present_ptes mm/memory.c:1576 [inline]
do_zap_pte_range mm/memory.c:1709 [inline]
zap_pte_range mm/memory.c:1753 [inline]
zap_pmd_range mm/memory.c:1845 [inline]
zap_pud_range mm/memory.c:1874 [inline]
zap_p4d_range mm/memory.c:1895 [inline]
unmap_page_range+0xe80/0x41c0 mm/memory.c:1916
unmap_single_vma mm/memory.c:1959 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2003
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x420 kernel/fork.c:1120
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x2300 kernel/exit.c:947
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f16a778e929
Code: Unable to access opcode bytes at 0x7f16a778e8ff.
RSP: 002b:00007f16a86580e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f16a79b5fa8 RCX: 00007f16a778e929
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f16a79b5fa8
RBP: 00007f16a79b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f16a79b5fac
R13: 0000000000000000 R14: 00007fffdcda46d0 R15: 00007fffdcda47b8
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pidfs_free_pid+0xaf/0x140 fs/pidfs.c:162
Code: f0 ff ff 73 e4 43 80 3c 3c 00 74 08 4c 89 f7 e8 a7 1b de ff 49 83 3e 00 0f 85 84 00 00 00 e8 08 f2 79 ff 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 82 1b de ff 4c 8b 33 4d 85 f6 74
RSP: 0018:ffffc90000007b90 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880263e0000
RDX: 0000000000000100 RSI: 0000000000000001 RDI: ffff8880a93df570
RBP: 0000000000000001 R08: ffff8880a93df503 R09: 1ffff1101527bea0
R10: dffffc0000000000 R11: ffffed101527bea1 R12: 1ffff1101527bead
R13: ffffffff81a83684 R14: ffff8880a93df568 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8719df3c60 CR3: 0000000064cb0000 CR4: 00000000003526f0
DR0: 0000000000000007 DR1: 0000000000000001 DR2: 0000000000000007
DR3: 00000000000002d5 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: f0 ff lock (bad)
2: ff 73 e4 push -0x1c(%rbx)
5: 43 80 3c 3c 00 cmpb $0x0,(%r12,%r15,1)
a: 74 08 je 0x14
c: 4c 89 f7 mov %r14,%rdi
f: e8 a7 1b de ff call 0xffde1bbb
14: 49 83 3e 00 cmpq $0x0,(%r14)
18: 0f 85 84 00 00 00 jne 0xa2
1e: e8 08 f2 79 ff call 0xff79f22b
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 82 1b de ff call 0xffde1bbb
39: 4c 8b 33 mov (%rbx),%r14
3c: 4d 85 f6 test %r14,%r14
3f: 74 .byte 0x74