================================================================== BUG: KASAN: use-after-free in lmWriteRecord+0x4c8/0x1aa0 fs/jfs/jfs_logmgr.c:433 Read of size 32 at addr ffff8880285a4e00 by task syz.6.447/6566 CPU: 1 PID: 6566 Comm: syz.6.447 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x25/0x60 mm/kasan/shadow.c:65 lmWriteRecord+0x4c8/0x1aa0 fs/jfs/jfs_logmgr.c:433 lmLog+0x6f6/0xa30 fs/jfs/jfs_logmgr.c:314 dtLog fs/jfs/jfs_txnmgr.c:1653 [inline] txLog fs/jfs/jfs_txnmgr.c:1401 [inline] txCommit+0x1c49/0x5200 fs/jfs/jfs_txnmgr.c:1265 jfs_mkdir+0x8d5/0xad0 fs/jfs/namei.c:290 vfs_mkdir+0x387/0x570 fs/namei.c:4073 do_mkdirat+0x1df/0x5b0 fs/namei.c:4098 __do_sys_mkdirat fs/namei.c:4113 [inline] __se_sys_mkdirat fs/namei.c:4111 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7e5467cb97 Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7e52473e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f7e52473ee0 RCX: 00007f7e5467cb97 RDX: 00000000000001ff RSI: 0000200000000000 RDI: 00000000ffffff9c RBP: 00002000000002c0 R08: 0000200000000080 R09: 0000000000000000 R10: 00002000000002c0 R11: 0000000000000246 R12: 0000200000000000 R13: 00007f7e52473ea0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4474: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 vm_area_dup+0x1e/0xb0 kernel/fork.c:358 __split_vma+0xb1/0x410 mm/mmap.c:2730 __do_munmap+0x383/0xdf0 mm/mmap.c:2856 __vm_munmap+0x140/0x240 mm/mmap.c:2952 __do_sys_munmap mm/mmap.c:2978 [inline] __se_sys_munmap mm/mmap.c:2974 [inline] __x64_sys_munmap+0x67/0x70 mm/mmap.c:2974 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 4474: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 remove_vma mm/mmap.c:188 [inline] remove_vma_list mm/mmap.c:2628 [inline] __do_munmap+0xc81/0xdf0 mm/mmap.c:2902 __vm_munmap+0x140/0x240 mm/mmap.c:2952 __do_sys_munmap mm/mmap.c:2978 [inline] __se_sys_munmap mm/mmap.c:2974 [inline] __x64_sys_munmap+0x67/0x70 mm/mmap.c:2974 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff8880285a4d68 which belongs to the cache vm_area_struct of size 200 The buggy address is located 152 bytes inside of 200-byte region [ffff8880285a4d68, ffff8880285a4e30) The buggy address belongs to the page: page:ffffea0000a16900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x285a4 memcg:ffff888055f4c901 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888140007a00 raw: 0000000000000000 00000000000f000f 00000001ffffffff ffff888055f4c901 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4474, ts 139620844787, free_ts 135058756033 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5487 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x195/0x290 mm/slub.c:3238 vm_area_dup+0x1e/0xb0 kernel/fork.c:358 __split_vma+0xb1/0x410 mm/mmap.c:2730 __do_munmap+0x383/0xdf0 mm/mmap.c:2856 __vm_munmap+0x140/0x240 mm/mmap.c:2952 __do_sys_munmap mm/mmap.c:2978 [inline] __se_sys_munmap mm/mmap.c:2974 [inline] __x64_sys_munmap+0x67/0x70 mm/mmap.c:2974 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_slab mm/slub.c:2020 [inline] discard_slab mm/slub.c:2026 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2512 put_cpu_partial+0x12d/0x190 mm/slub.c:2592 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 ptlock_alloc+0x1c/0x60 mm/memory.c:5556 ptlock_init include/linux/mm.h:2241 [inline] pgtable_pte_page_ctor include/linux/mm.h:2268 [inline] __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline] pte_alloc_one+0xc0/0x310 arch/x86/mm/pgtable.c:33 __pte_alloc+0x21/0x150 mm/memory.c:439 copy_pte_range mm/memory.c:1032 [inline] copy_pmd_range mm/memory.c:1167 [inline] copy_pud_range mm/memory.c:1204 [inline] copy_p4d_range mm/memory.c:1228 [inline] copy_page_range+0x29c2/0x3230 mm/memory.c:1301 dup_mmap kernel/fork.c:615 [inline] dup_mm kernel/fork.c:1466 [inline] copy_mm+0xc86/0x13f0 kernel/fork.c:1518 copy_process+0x17eb/0x3e20 kernel/fork.c:2290 kernel_clone+0x23f/0x990 kernel/fork.c:2679 Memory state around the buggy address: ffff8880285a4d00: fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb fb ffff8880285a4d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880285a4e00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb ^ ffff8880285a4e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880285a4f00: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc ==================================================================