slab radix_tree_node start ffff8880445ce000 pointer offset 24 size 576 BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 43300067 P4D 43300067 PUD 4f195067 PMD 0 Oops: Oops: 0010 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 UID: 0 PID: 6415 Comm: syz.4.91 Not tainted 6.14.0-rc1-syzkaller-g5c8c229261f1-dirty #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc90000007bd8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 1ffff110088b9c04 RCX: 9d652f5789475c00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8880445ce018 RBP: ffffc90000007e10 R08: ffffffff819f146c R09: 1ffff11003f8519a R10: dffffc0000000000 R11: 0000000000000000 R12: ffffffff81a6d507 R13: ffff8880445ce020 R14: 0000000000000000 R15: ffff8880445ce018 FS: 00007f876c1686c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000051892000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 fa 3b 8b 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90002b0f080 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000561e1c RCX: ffff88800076af28 RDX: dffffc0000000000 RSI: ffffffff8c0ab8e0 RDI: ffffffff8c608a00 RBP: ffffc90002b0f1d8 R08: ffffffff942f9847 R09: 1ffffffff285f308 R10: dffffc0000000000 R11: fffffbfff285f309 R12: 1ffff92000561e18 R13: dffffc0000000000 R14: ffffc90002b0f0e0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __set_page_owner+0x9e/0x800 mm/page_owner.c:322 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 folio_alloc_mpol_noprof+0x36/0x70 mm/mempolicy.c:2289 shmem_alloc_folio mm/shmem.c:1863 [inline] shmem_alloc_and_add_folio+0x4a0/0x1090 mm/shmem.c:1902 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2522 shmem_get_folio mm/shmem.c:2628 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3278 generic_perform_write+0x346/0x990 mm/filemap.c:4189 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3454 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f876b38b85f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f876c167df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f876b38b85f RDX: 0000000001000000 RSI: 00007f8762000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005939 R10: 0000000020005b42 R11: 0000000000000293 R12: 0000000000000003 R13: 00007f876c167ef0 R14: 00007f876c167eb0 R15: 00007f8762000000 </TASK> Modules linked in: CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc90000007bd8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 1ffff110088b9c04 RCX: 9d652f5789475c00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8880445ce018 RBP: ffffc90000007e10 R08: ffffffff819f146c R09: 1ffff11003f8519a R10: dffffc0000000000 R11: 0000000000000000 R12: ffffffff81a6d507 R13: ffff8880445ce020 R14: 0000000000000000 R15: ffff8880445ce018 FS: 00007f876c1686c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000051892000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 fa 3b 8b 00 call 0x8b3c06 c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 85 01 00 00 jne 0x19c 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25