================================================================== BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x38cd/0x39e0 fs/jfs/jfs_dtree.c:1522 Read of size 1 at addr ffff88805283926d by task syz.5.648/8894 CPU: 0 UID: 0 PID: 8894 Comm: syz.5.648 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 dtSplitPage+0x38cd/0x39e0 fs/jfs/jfs_dtree.c:1522 dtSplitUp+0x7ba/0x5970 fs/jfs/jfs_dtree.c:1092 dtInsert+0x8dd/0xb60 fs/jfs/jfs_dtree.c:871 jfs_symlink+0x738/0x10e0 fs/jfs/namei.c:1020 vfs_symlink fs/namei.c:4730 [inline] vfs_symlink+0x403/0x680 fs/namei.c:4714 do_symlinkat+0x261/0x310 fs/namei.c:4756 __do_sys_symlink fs/namei.c:4777 [inline] __se_sys_symlink fs/namei.c:4775 [inline] __x64_sys_symlink+0x75/0x90 fs/namei.c:4775 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f395038ebe9 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:00007f39511f3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007f39505b5fa0 RCX: 00007f395038ebe9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000200000000080 RBP: 00007f3950411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f39505b6038 R14: 00007f39505b5fa0 R15: 00007fffebc526d8 Allocated by task 8894: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_lru_noprof+0x1d0/0x3b0 mm/slub.c:4248 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105 alloc_inode+0x64/0x240 fs/inode.c:346 iget_locked+0x2e4/0x830 fs/inode.c:1438 jfs_iget+0x1e/0x4c0 fs/jfs/inode.c:29 jfs_lookup+0x2b2/0x380 fs/jfs/namei.c:1469 __lookup_slow+0x251/0x460 fs/namei.c:1808 lookup_slow fs/namei.c:1825 [inline] walk_component+0x353/0x5b0 fs/namei.c:2129 lookup_last fs/namei.c:2630 [inline] path_lookupat+0x142/0x6d0 fs/namei.c:2654 filename_lookup+0x224/0x5f0 fs/namei.c:2683 user_path_at+0x3a/0x60 fs/namei.c:3127 __do_sys_chdir fs/open.c:561 [inline] __se_sys_chdir fs/open.c:555 [inline] __x64_sys_chdir+0xbe/0x270 fs/open.c:555 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888052838938 which belongs to the cache jfs_ip of size 2232 The buggy address is located 125 bytes to the right of allocated 2232-byte region [ffff888052838938, ffff8880528391f0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888052838000 pfn:0x52838 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888079b05401 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff888147acf640 dead000000000122 0000000000000000 raw: ffff888052838000 00000000800d0009 00000000f5000000 ffff888079b05401 head: 00fff00000000040 ffff888147acf640 dead000000000122 0000000000000000 head: ffff888052838000 00000000800d0009 00000000f5000000 ffff888079b05401 head: 00fff00000000003 ffffea00014a0e01 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 6440, tgid 6439 (syz.2.106), ts 173708860027, free_ts 136015570382 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_lru_noprof+0xf4/0x3b0 mm/slub.c:4248 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105 alloc_inode+0x64/0x240 fs/inode.c:346 new_inode+0x22/0x1c0 fs/inode.c:1145 jfs_fill_super+0x6a8/0x1040 fs/jfs/super.c:511 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1692 vfs_get_tree+0x8e/0x340 fs/super.c:1815 do_new_mount fs/namespace.c:3808 [inline] path_mount+0x1513/0x2000 fs/namespace.c:4123 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount fs/namespace.c:4324 [inline] __x64_sys_mount+0x28d/0x310 fs/namespace.c:4324 page last free pid 5921 tgid 5921 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:322 getname include/linux/fs.h:2918 [inline] getname_maybe_null include/linux/fs.h:2925 [inline] getname_maybe_null include/linux/fs.h:2922 [inline] vfs_fstatat+0xe1/0xf0 fs/stat.c:370 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888052839100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888052839180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc >ffff888052839200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc 00 00 ^ ffff888052839280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888052839300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== find_entry called with index = 0 read_mapping_page failed! ERROR: (device loop5): txAbort: