BUG: kernel NULL pointer dereference, address: 0000000000000dc0 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 800000004c293067 P4D 800000004c293067 PUD 7b042067 PMD 0 Oops: Oops: 0010 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 5494 Comm: syz.0.49 Not tainted 6.11.0-rc5-next-20240827-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:0xdc0 Code: Unable to access opcode bytes at 0xd96. RSP: 0018:ffffc90009187818 EFLAGS: 00010046 ================================================================== BUG: KASAN: stack-out-of-bounds in __show_regs+0xdc/0x610 arch/x86/kernel/process_64.c:83 Read of size 8 at addr ffffc900091877c0 by task syz.0.49/5494 CPU: 1 UID: 0 PID: 5494 Comm: syz.0.49 Not tainted 6.11.0-rc5-next-20240827-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __show_regs+0xdc/0x610 arch/x86/kernel/process_64.c:83 show_regs arch/x86/kernel/dumpstack.c:472 [inline] __die_body+0x3c/0xb0 arch/x86/kernel/dumpstack.c:420 page_fault_oops+0x8e4/0xcc0 arch/x86/mm/fault.c:711 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5ed/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:0xdc0 Code: Unable to access opcode bytes at 0xd96. RSP: 0018:ffffc90009187818 EFLAGS: 00010046 RAX: 962f36debd9e6000 RBX: dffffc0000000000 RCX: ffffc90009187703 RDX: 0000000000000005 RSI: ffffffff8c0adc40 RDI: ffffffff8c6088c0 RBP: ffff8880166f9280 R08: ffffffff901c362f R09: 1ffffffff20386c5 R10: dffffc0000000000 R11: fffffbfff20386c6 R12: 962f36debd9e6000 R13: 0000000000000006 R14: ffffffff8205dbd9 R15: 0000000000000001 </TASK> The buggy address belongs to stack of task syz.0.49/5494 and is located at offset 512 in frame: page_fault_oops+0x0/0xcc0 This frame has 7 objects: [32, 36) 'level.i' [48, 49) 'nx.i' [64, 65) 'rw.i' [80, 90) 'idt.i' [112, 122) 'gdt.i' [144, 146) 'ldtr.i' [160, 192) 'info' The buggy address belongs to the virtual mapping at [ffffc90009180000, ffffc90009189000) created by: copy_process+0x5d1/0x3d50 kernel/fork.c:2203 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804cc30d80 pfn:0x4cc30 memcg:ffff8880236a6e82 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff88804cc30d80 0000000000000000 00000001ffffffff ffff8880236a6e82 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 5491, tgid 5491 (syz.0.49), ts 96548238007, free_ts 94253638483 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1520 prep_new_page mm/page_alloc.c:1528 [inline] get_page_from_freelist+0x312a/0x3270 mm/page_alloc.c:3479 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 vm_area_alloc_pages mm/vmalloc.c:3600 [inline] __vmalloc_area_node mm/vmalloc.c:3669 [inline] __vmalloc_node_range_noprof+0xa40/0x1400 mm/vmalloc.c:3850 alloc_thread_stack_node kernel/fork.c:314 [inline] dup_task_struct+0x444/0x8c0 kernel/fork.c:1115 copy_process+0x5d1/0x3d50 kernel/fork.c:2203 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 __do_sys_clone3 kernel/fork.c:3088 [inline] __se_sys_clone3+0x2cb/0x350 kernel/fork.c:3067 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 page last free pid 5281 tgid 5281 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1101 [inline] free_unref_page+0xc64/0xe80 mm/page_alloc.c:2654 vfree+0x186/0x2e0 mm/vmalloc.c:3380 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3301 process_one_work kernel/workqueue.c:3232 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3313 worker_thread+0x86d/0xd10 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffffc90009187680: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90009187700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90009187780: 00 00 00 00 00 00 00 00 f3 f3 f3 f3 00 00 00 00 ^ ffffc90009187800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90009187880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================