================================================================== BUG: KASAN: stack-out-of-bounds in symbol_string+0xb6/0x3b0 lib/vsprintf.c:987 Write of size 666 at addr ffffc900090e74e0 by task syz.3.48/5557 CPU: 0 UID: 0 PID: 5557 Comm: syz.3.48 Tainted: G D 6.11.0-rc4-next-20240820-syzkaller #0 Tainted: [D]=DIE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __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 The buggy address belongs to stack of task syz.3.48/5557 The buggy address belongs to the virtual mapping at [ffffc900090e0000, ffffc900090e9000) created by: copy_process+0x5d1/0x3d50 kernel/fork.c:2206 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804e6dee88 pfn:0x4e6de memcg:ffff88802496fb02 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: ffff88804e6dee88 0000000000000000 00000001ffffffff ffff88802496fb02 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 5475, tgid 5475 (syz.1.31), ts 91455685686, free_ts 86850602565 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1517 prep_new_page mm/page_alloc.c:1525 [inline] get_page_from_freelist+0x3004/0x30c0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x29e/0x780 mm/page_alloc.c:4743 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:2206 kernel_clone+0x226/0x8f0 kernel/fork.c:2787 __do_sys_clone3 kernel/fork.c:3091 [inline] __se_sys_clone3+0x2cb/0x350 kernel/fork.c:3070 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 5448 tgid 5438 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1098 [inline] free_unref_folios+0xe8a/0x1850 mm/page_alloc.c:2699 folios_put_refs+0x76e/0x860 mm/swap.c:1007 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:332 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x496/0xc40 mm/mmap.c:1934 __mmput+0x115/0x390 kernel/fork.c:1347 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x176f/0x1810 kernel/signal.c:2936 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffffc900090e7500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc900090e7580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc900090e7600: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 ^ ffffc900090e7680: 00 00 00 f2 f2 f2 f2 f2 04 f3 f3 f3 00 00 00 00 ffffc900090e7700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 02 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 800000005ddbb067 P4D 800000005ddbb067 PUD 2fcb8067 PMD 0 Oops: Oops: 0010 [#2] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 5557 Comm: syz.3.48 Tainted: G B D 6.11.0-rc4-next-20240820-syzkaller #0 Tainted: [B]=BAD_PAGE, [D]=DIE Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc900090e7430 EFLAGS: 00010082 RAX: ffff88807af70001 RBX: dffffc0000000000 RCX: 0000000000040000 RDX: ffffc9000a8df000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 0000000000000000 R08: ffffffff8155a2df R09: 1ffffffff2628614 R10: dffffc0000000000 R11: fffffbfff2628615 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8e7d1aa0 R15: dffffc0000000000 FS: 00007fe42753a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000007b878000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: Modules linked in: CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 2b80:.str.32+0x0/0x60 Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <73> 74 61 63 6b 2d 70 72 6f 74 65 63 74 6f 72 3a 20 4b 65 72 6e 65 RSP: 0000:ffffffff8c0995f1 EFLAGS: ffffc900090e7ab8 ORIG_RAX: 000000000000002f RAX: 0000000041b58ab3 RBX: 0000000045e0360e RCX: 0000000000040000 RDX: ffffc9000a8df000 RSI: a1ec9a4932780c00 RDI: ffffffff8bb48368 RBP: ffff0000ffffff00 R08: ffffffff8c0995f1 R09: 00000000fffffff7 R10: ffffffff8bb497d0 R11: ffffffff8e28f9e6 R12: ffffffff8bb4b650 R13: ffffffff8e28f9f8 R14: 0000000041b58ab3 R15: ffffffff8c0995ef FS: 00007fe42753a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 2b80 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000007b878000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 28: 00 00 add %al,(%rax) * 2a: 73 74 jae 0xa0 <-- trapping instruction 2c: 61 (bad) 2d: 63 6b 2d movsxd 0x2d(%rbx),%ebp 30: 70 72 jo 0xa4 32: 6f outsl %ds:(%rsi),(%dx) 33: 74 65 je 0x9a 35: 63 74 6f 72 movsxd 0x72(%rdi,%rbp,2),%esi 39: 3a 20 cmp (%rax),%ah 3b: 4b rex.WXB 3c: 65 72 6e gs jb 0xad 3f: 65 gs