================================================================== BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1 Read of size 1 at addr ffff88804b9b91dd by task syz.0.558/9209 CPU: 1 UID: 0 PID: 9209 Comm: syz.0.558 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871 jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137 lookup_open fs/namei.c:4440 [inline] open_last_lookups fs/namei.c:4540 [inline] path_openat+0x18bb/0x3dd0 fs/namei.c:4784 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_creat fs/open.c:1514 [inline] __se_sys_creat fs/open.c:1508 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1508 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fefb178f749 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:00007fefb2615038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fefb19e6090 RCX: 00007fefb178f749 RDX: 0000000000000000 RSI: 0000000000000029 RDI: 0000200000000280 RBP: 00007fefb1813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fefb19e6128 R14: 00007fefb19e6090 R15: 00007ffd3791b288 Allocated by task 9195: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5282 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 iget_locked+0x131/0x6a0 fs/inode.c:1470 jfs_iget+0x24/0x470 fs/jfs/inode.c:29 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469 __lookup_slow+0x297/0x3d0 fs/namei.c:1858 lookup_slow+0x53/0x70 fs/namei.c:1875 walk_component fs/namei.c:2221 [inline] lookup_last fs/namei.c:2722 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2746 filename_lookup+0x212/0x570 fs/namei.c:2775 user_path_at+0x3a/0x60 fs/namei.c:3567 __do_sys_chdir fs/open.c:558 [inline] __se_sys_chdir+0x91/0x280 fs/open.c:552 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88804b9b8928 which belongs to the cache jfs_ip of size 2216 The buggy address is located 13 bytes to the right of allocated 2216-byte region [ffff88804b9b8928, ffff88804b9b91d0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4b9b8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888026b52301 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b7fb780 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff888026b52301 head: 00fff00000000040 ffff88801b7fb780 dead000000000122 0000000000000000 head: 0000000000000000 00000000800d000d 00000000f5000000 ffff888026b52301 head: 00fff00000000003 ffffea00012e6e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6841, tgid 6839 (syz.0.163), ts 177439139675, free_ts 174480297419 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf2b/0x1960 mm/slub.c:4656 __slab_alloc+0x65/0x100 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] kmem_cache_alloc_lru_noprof+0x3fe/0x6e0 mm/slub.c:5282 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1175 jfs_fill_super+0x569/0xd80 fs/jfs/super.c:511 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4201 page last free pid 37 tgid 37 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943 discard_slab mm/slub.c:3346 [inline] __put_partials+0x146/0x170 mm/slub.c:3886 put_cpu_partial+0x1f2/0x2d0 mm/slub.c:3961 __slab_free+0x288/0x2a0 mm/slub.c:5952 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] __kmalloc_cache_node_noprof+0x409/0x700 mm/slub.c:5784 kmalloc_node_noprof include/linux/slab.h:983 [inline] __get_vm_area_node+0x13f/0x300 mm/vmalloc.c:3208 __vmalloc_node_range_noprof+0x371/0x16a0 mm/vmalloc.c:4011 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:4111 alloc_thread_stack_node kernel/fork.c:354 [inline] dup_task_struct+0x228/0x9a0 kernel/fork.c:923 copy_process+0x4ea/0x3950 kernel/fork.c:2052 kernel_clone+0x21e/0x820 kernel/fork.c:2651 user_mode_thread+0xdd/0x140 kernel/fork.c:2727 call_usermodehelper_exec_sync kernel/umh.c:132 [inline] call_usermodehelper_exec_work+0x9c/0x230 kernel/umh.c:163 Memory state around the buggy address: ffff88804b9b9080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804b9b9100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88804b9b9180: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff88804b9b9200: fc fc fc fc fc fc fc fc fc fc fa fb fb fb fb fb ffff88804b9b9280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================