================================================================== BUG: KASAN: slab-out-of-bounds in dtInsertEntry+0xd74/0x1270 fs/jfs/jfs_dtree.c:4063 Read of size 4 at addr ffff88805fc41b4c by task syz.4.98/4851 CPU: 0 PID: 4851 Comm: syz.4.98 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 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 dtInsertEntry+0xd74/0x1270 fs/jfs/jfs_dtree.c:4063 dtSplitPage+0x2501/0x3200 fs/jfs/jfs_dtree.c:1596 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0xff4/0x5830 fs/jfs/jfs_dtree.c:871 jfs_symlink+0x8b2/0xfb0 fs/jfs/namei.c:1019 vfs_symlink+0x247/0x3d0 fs/namei.c:4437 do_symlinkat+0x1ab/0x6b0 fs/namei.c:4466 __do_sys_symlink fs/namei.c:4488 [inline] __se_sys_symlink fs/namei.c:4486 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4486 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: 0033:0x7f201e09cf79 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f201c2f7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007f201e316fa0 RCX: 00007f201e09cf79 RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000200000000100 RBP: 00007f201e1337e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f201e317038 R14: 00007f201e316fa0 R15: 00007ffe46ef5db8 Allocated by task 4851: 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 jfs_alloc_inode+0x17/0x50 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] iget_locked+0x191/0x820 fs/inode.c:1308 jfs_iget+0x20/0x3f0 fs/jfs/inode.c:29 jfs_lookup+0x21d/0x420 fs/jfs/namei.c:1467 __lookup_slow+0x29d/0x410 fs/namei.c:1671 lookup_slow+0x53/0x70 fs/namei.c:1688 walk_component+0x319/0x460 fs/namei.c:1984 lookup_last fs/namei.c:2439 [inline] path_lookupat+0x169/0x440 fs/namei.c:2463 filename_lookup+0x214/0x540 fs/namei.c:2492 user_path_at_empty+0x40/0x190 fs/namei.c:2891 user_path_at include/linux/namei.h:57 [inline] __do_sys_chdir fs/open.c:490 [inline] __se_sys_chdir+0x98/0x280 fs/open.c:484 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 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x950 kernel/rcu/tree.c:3091 destroy_inode fs/inode.c:316 [inline] evict+0x834/0x8d0 fs/inode.c:662 jfs_put_super+0x144/0x190 fs/jfs/super.c:201 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88805fc41280 which belongs to the cache jfs_ip of size 2240 The buggy address is located 12 bytes to the right of 2240-byte region [ffff88805fc41280, ffff88805fc41b40) The buggy address belongs to the page: page:ffffea00017f1000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fc40 head:ffffea00017f1000 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88805facbc01 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88814672fc80 raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff88805facbc01 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 4421, ts 67688014681, free_ts 67565171137 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 jfs_alloc_inode+0x17/0x50 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] iget_locked+0x191/0x820 fs/inode.c:1308 jfs_iget+0x20/0x3f0 fs/jfs/inode.c:29 jfs_fill_super+0x73b/0xb00 fs/jfs/super.c:585 mount_bdev+0x287/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 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 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 anon_vma_chain_alloc mm/rmap.c:138 [inline] __anon_vma_prepare+0x66/0x410 mm/rmap.c:192 anon_vma_prepare include/linux/rmap.h:152 [inline] do_anonymous_page mm/memory.c:3836 [inline] handle_pte_fault mm/memory.c:4648 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x3be0/0x4410 mm/memory.c:4883 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:205 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] copyout lib/iov_iter.c:157 [inline] copy_page_to_iter_iovec lib/iov_iter.c:228 [inline] __copy_page_to_iter lib/iov_iter.c:861 [inline] copy_page_to_iter+0x49e/0x910 lib/iov_iter.c:889 filemap_read+0x1e2d/0x2540 mm/filemap.c:2698 blkdev_read_iter+0x11d/0x150 block/fops.c:563 Memory state around the buggy address: ffff88805fc41a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805fc41a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805fc41b00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88805fc41b80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88805fc41c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================