================================================================== BUG: KASAN: slab-out-of-bounds in user_mode arch/x86/include/asm/ptrace.h:131 [inline] BUG: KASAN: slab-out-of-bounds in trace_page_fault_entries arch/x86/mm/fault.c:1516 [inline] BUG: KASAN: slab-out-of-bounds in do_page_fault+0x6d/0x320 arch/x86/mm/fault.c:1528 Read of size 8 at addr ffff8881eb2e7f20 by task syz.4.771/3104 CPU: 1 PID: 3104 Comm: syz.4.771 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: Allocated by task 1: (stack is not available) Freed by task 3945690672: (stack is not available) The buggy address belongs to the object at ffff8881eb2e6600 which belongs to the cache names_cache of size 4096 The buggy address is located 2336 bytes to the right of 4096-byte region [ffff8881eb2e6600, ffff8881eb2e7600) The buggy address belongs to the page: page:ffffea0007acb800 refcount:1 mapcount:0 mapping:ffff8881f5d01b80 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5d01b80 raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated 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+0x35e/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894 alloc_slab_page+0x3c/0x3b0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x93/0x420 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x29e/0x420 mm/slub.c:2667 __slab_alloc+0x63/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0x12c/0x270 mm/slub.c:2842 getname_flags+0xb9/0x500 fs/namei.c:141 user_path_at_empty+0x2f/0x50 fs/namei.c:2703 user_path_at include/linux/namei.h:49 [inline] vfs_statx+0x116/0x200 fs/stat.c:187 vfs_fstatat include/linux/fs.h:3389 [inline] __do_sys_newfstatat fs/stat.c:367 [inline] __se_sys_newfstatat+0xcc/0x350 fs/stat.c:361 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:361 do_syscall_64+0xcf/0x170 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+0x7e4/0x910 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4956 [inline] __free_pages+0x8c/0x110 mm/page_alloc.c:4962 __free_slab+0x218/0x2d0 mm/slub.c:1774 free_slab mm/slub.c:1789 [inline] discard_slab mm/slub.c:1795 [inline] unfreeze_partials+0x165/0x1a0 mm/slub.c:2288 put_cpu_partial+0xc1/0x180 mm/slub.c:2324 __slab_free+0x2be/0x380 mm/slub.c:2971 do_slab_free mm/slub.c:3068 [inline] ___cache_free+0xbb/0xd0 mm/slub.c:3087 qlink_free+0x23/0x30 mm/kasan/quarantine.c:148 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:167 quarantine_reduce+0x1a8/0x200 mm/kasan/quarantine.c:260 __kasan_kmalloc+0x42/0x200 mm/kasan/common.c:507 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537 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+0xe2/0x270 mm/slub.c:2842 getname_flags+0xb9/0x500 fs/namei.c:141 user_path_at_empty+0x2f/0x50 fs/namei.c:2703 user_path_at include/linux/namei.h:49 [inline] vfs_statx+0x116/0x200 fs/stat.c:187 Memory state around the buggy address: ffff8881eb2e7e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881eb2e7e80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff8881eb2e7f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881eb2e7f80: f1 f1 f1 f1 00 f2 f2 f2 04 f3 f3 f3 fc fc fc fc ffff8881eb2e8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== PANIC: double fault, error_code: 0x0 CPU: 1 PID: 3104 Comm: syz.4.771 Tainted: G B 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__kasan_report+0x4/0x120 mm/kasan/report.c:485 Code: 07 49 83 c7 18 48 85 c0 75 e6 65 ff 0d 61 21 75 7e 0f 85 50 ff ff ff e8 7a db 72 ff e9 46 ff ff ff 0f 1f 44 00 00 55 48 89 e5 <41> 57 41 56 41 55 41 54 53 48 83 ec 40 65 48 8b 04 25 28 00 00 00 RSP: 0018:ffff8881eb030000 EFLAGS: 00010082 RAX: 8a89fd6889c4ae00 RBX: 0000000000000082 RCX: ffffffff812deaed RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8881eb030120 RBP: ffff8881eb030000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881eb030120 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881eb030098 FS: 00005555927b4500(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff8881eb02fff8 CR3: 00000001f5c2a000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 49 83 c7 18 add $0x18,%r15 4: 48 85 c0 test %rax,%rax 7: 75 e6 jne 0xffffffef 9: 65 ff 0d 61 21 75 7e decl %gs:0x7e752161(%rip) # 0x7e752171 10: 0f 85 50 ff ff ff jne 0xffffff66 16: e8 7a db 72 ff call 0xff72db95 1b: e9 46 ff ff ff jmp 0xffffff66 20: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 25: 55 push %rbp 26: 48 89 e5 mov %rsp,%rbp * 29: 41 57 push %r15 <-- trapping instruction 2b: 41 56 push %r14 2d: 41 55 push %r13 2f: 41 54 push %r12 31: 53 push %rbx 32: 48 83 ec 40 sub $0x40,%rsp 36: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 3d: 00 00