================================================================== BUG: KASAN: use-after-free in ciCompare fs/jfs/jfs_dtree.c:3416 [inline] BUG: KASAN: use-after-free in dtSearch+0x164c/0x2050 fs/jfs/jfs_dtree.c:645 Read of size 1 at addr ffff88807066f494 by task syz.9.1700/13335 CPU: 0 PID: 13335 Comm: syz.9.1700 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 ciCompare fs/jfs/jfs_dtree.c:3416 [inline] dtSearch+0x164c/0x2050 fs/jfs/jfs_dtree.c:645 jfs_lookup+0x152/0x380 fs/jfs/namei.c:1459 lookup_open fs/namei.c:3468 [inline] open_last_lookups fs/namei.c:3558 [inline] path_openat+0xfaf/0x2e70 fs/namei.c:3788 do_filp_open+0x1c1/0x3c0 fs/namei.c:3818 do_sys_openat2+0x142/0x490 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f919658f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f919742e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f91967e5fa0 RCX: 00007f919658f749 RDX: 0000000000042042 RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007f9196613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000014a R11: 0000000000000246 R12: 0000000000000000 R13: 00007f91967e6038 R14: 00007f91967e5fa0 R15: 00007ffef5960858 Allocated by task 5810: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] jfs_alloc_inode+0x24/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 ialloc+0x48/0x950 fs/jfs/jfs_inode.c:48 jfs_mkdir+0x190/0xa70 fs/jfs/namei.c:225 vfs_mkdir+0x387/0x570 fs/namei.c:4114 ovl_do_mkdir fs/overlayfs/overlayfs.h:186 [inline] ovl_mkdir_real+0xc2/0x2a0 fs/overlayfs/dir.c:146 ovl_workdir_create+0x330/0x7a0 fs/overlayfs/super.c:799 ovl_make_workdir fs/overlayfs/super.c:1389 [inline] ovl_get_workdir+0x388/0x1540 fs/overlayfs/super.c:1539 ovl_fill_super+0x1925/0x2ae0 fs/overlayfs/super.c:2095 mount_nodev+0x52/0xe0 fs/super.c:1489 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x154/0x980 kernel/rcu/tree.c:2849 destroy_inode fs/inode.c:316 [inline] evict+0x7da/0x870 fs/inode.c:720 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline] jfs_lazycommit+0x427/0xa50 fs/jfs/jfs_txnmgr.c:2733 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88807066ef00 which belongs to the cache jfs_ip of size 2240 The buggy address is located 1428 bytes inside of 2240-byte region [ffff88807066ef00, ffff88807066f7c0) The buggy address belongs to the physical page: page:ffffea0001c19a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807066ef00 pfn:0x70668 head:ffffea0001c19a00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88807a203001 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801bbef640 raw: ffff88807066ef00 00000000800d000b 00000001ffffffff ffff88807a203001 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 4931, tgid 4930 (syz.3.130), ts 130025734966, free_ts 71329215306 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] jfs_alloc_inode+0x24/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 jfs_fill_super+0x392/0xac0 fs/jfs/super.c:544 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3525 release_pages+0x1f92/0x2200 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xff/0x210 mm/mmu_gather.c:261 tlb_finish_mmu+0xbd/0x1c0 mm/mmu_gather.c:361 unmap_region+0x272/0x2c0 mm/mmap.c:2343 do_mas_align_munmap+0xc57/0x1220 mm/mmap.c:2592 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __vm_munmap+0x18d/0x290 mm/mmap.c:2936 __do_sys_munmap mm/mmap.c:2961 [inline] __se_sys_munmap mm/mmap.c:2958 [inline] __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2958 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88807066f380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807066f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807066f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807066f500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807066f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================