================================================================== BUG: KASAN: use-after-free in user_mode arch/x86/include/asm/ptrace.h:131 [inline] BUG: KASAN: use-after-free in trace_page_fault_entries arch/x86/mm/fault.c:1516 [inline] BUG: KASAN: use-after-free in do_page_fault+0x66/0x330 arch/x86/mm/fault.c:1528 Read of size 8 at addr ffff8881e531fee0 by task syz.2.471/2139 CPU: 1 PID: 2139 Comm: syz.2.471 Not tainted 5.4.289-syzkaller-00030-gcb850525fc3e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: The buggy address belongs to the page: page:ffffea000794c7c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x8000000000000000() raw: 8000000000000000 0000000000000000 ffffea000794c7c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0x109/0x250 mm/slub.c:2842 getname_flags+0xb8/0x4e0 fs/namei.c:141 user_path_at_empty+0x28/0x50 fs/namei.c:2703 user_path_at include/linux/namei.h:49 [inline] vfs_statx+0x115/0x210 fs/stat.c:187 vfs_fstatat include/linux/fs.h:3387 [inline] __do_sys_newfstatat fs/stat.c:367 [inline] __se_sys_newfstatat+0xce/0x770 fs/stat.c:361 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4955 [inline] __free_pages+0x91/0x140 mm/page_alloc.c:4961 __free_slab+0x221/0x2e0 mm/slub.c:1774 free_slab mm/slub.c:1789 [inline] discard_slab mm/slub.c:1795 [inline] unfreeze_partials+0x14e/0x180 mm/slub.c:2288 put_cpu_partial+0x44/0x180 mm/slub.c:2324 __slab_free+0x297/0x360 mm/slub.c:2971 qlist_free_all+0x43/0xb0 mm/kasan/quarantine.c:167 quarantine_reduce+0x1d9/0x210 mm/kasan/quarantine.c:260 __kasan_kmalloc+0x41/0x210 mm/kasan/common.c:507 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc_trace+0xdc/0x260 mm/slub.c:2854 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] selinux_bpf_map_alloc+0x4d/0x140 security/selinux/hooks.c:6897 security_bpf_map_alloc+0x5d/0x90 security/security.c:2425 map_create kernel/bpf/syscall.c:612 [inline] __do_sys_bpf kernel/bpf/syscall.c:2873 [inline] __se_sys_bpf+0x5bc7/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Memory state around the buggy address: ffff8881e531fd80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881e531fe00: ff ff ff ff ff ff ff ff ff ff ff ff 00 00 00 00 >ffff8881e531fe80: 00 00 00 00 ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881e531ff00: ff ff ff ff ff ff ff ff f1 f1 f1 f1 00 f2 f2 f2 ffff8881e531ff80: 04 f3 f3 f3 ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== PANIC: double fault, error_code: 0x0 CPU: 1 PID: 2139 Comm: syz.2.471 Tainted: G B 5.4.289-syzkaller-00030-gcb850525fc3e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:perf_trace_x86_exceptions+0x22/0x410 arch/x86/include/asm/trace/exceptions.h:14 Code: 00 00 00 00 00 0f 1f 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00 00 00 48 89 4c 24 30 48 89 54 24 28 <48> 89 74 24 18 48 89 7c 24 08 65 48 8b 04 25 28 00 00 00 48 89 84 RSP: 0018:ffff8881e507dfe0 EFLAGS: 00010082 RAX: 1ffff1103c91bd93 RBX: ffff8881e507e118 RCX: 0000000000000000 RDX: ffff8881e507e118 RSI: ffffe8fffef00e08 RDI: ffffffff85eb6be0 RBP: ffff8881e507e0c8 R08: ffffffff8130280e R09: fffffbfff0c98976 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881e48dec90 R13: dffffc0000000000 R14: ffffe8fffef00e08 R15: 0000000000000000 FS: 00007f6140ba86c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8881e507dfd8 CR3: 00000001f5c2a000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: <#DF> ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 0f 1f 00 nopl (%rax) 7: 55 push %rbp 8: 48 89 e5 mov %rsp,%rbp b: 41 57 push %r15 d: 41 56 push %r14 f: 41 55 push %r13 11: 41 54 push %r12 13: 53 push %rbx 14: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 18: 48 81 ec c0 00 00 00 sub $0xc0,%rsp 1f: 48 89 4c 24 30 mov %rcx,0x30(%rsp) 24: 48 89 54 24 28 mov %rdx,0x28(%rsp) * 29: 48 89 74 24 18 mov %rsi,0x18(%rsp) <-- trapping instruction 2e: 48 89 7c 24 08 mov %rdi,0x8(%rsp) 33: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 3a: 00 00 3c: 48 rex.W 3d: 89 .byte 0x89 3e: 84 .byte 0x84