================================================================== BUG: KASAN: slab-out-of-bounds in dtInsertEntry.isra.0+0x13a1/0x1670 fs/jfs/jfs_dtree.c:3765 Read of size 4 at addr ffff888055b7b6e4 by task syz.3.701/8256 CPU: 0 UID: 0 PID: 8256 Comm: syz.3.701 Not tainted 6.16.0-rc2-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 dtInsertEntry.isra.0+0x13a1/0x1670 fs/jfs/jfs_dtree.c:3765 dtSplitPage+0x2bd0/0x39e0 fs/jfs/jfs_dtree.c:1596 dtSplitUp+0x7ba/0x5970 fs/jfs/jfs_dtree.c:1092 dtInsert+0x8dd/0xb60 fs/jfs/jfs_dtree.c:871 jfs_mknod+0x593/0x9f0 fs/jfs/namei.c:1410 vfs_mknod+0x5da/0x8e0 fs/namei.c:4235 do_mknodat+0x30f/0x5d0 fs/namei.c:4295 __do_sys_mknod fs/namei.c:4318 [inline] __se_sys_mknod fs/namei.c:4316 [inline] __x64_sys_mknod+0x87/0xb0 fs/namei.c:4316 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: 0033:0x7f681b38e929 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:00007f681c263038 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 00007f681b5b6080 RCX: 00007f681b38e929 RDX: 0000000000000707 RSI: 0000000000002000 RDI: 0000200000000780 RBP: 00007f681b410b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f681b5b6080 R15: 00007ffcc7e18998 Allocated by task 8222: 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:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_lru_noprof+0x1d0/0x3b0 mm/slub.c:4216 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:1439 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:1817 lookup_slow fs/namei.c:1834 [inline] walk_component+0x353/0x5b0 fs/namei.c:2138 lookup_last fs/namei.c:2639 [inline] path_lookupat+0x142/0x6d0 fs/namei.c:2663 filename_lookup+0x224/0x5f0 fs/namei.c:2692 user_path_at+0x3a/0x60 fs/namei.c:3127 __do_sys_chdir fs/open.c:560 [inline] __se_sys_chdir fs/open.c:554 [inline] __x64_sys_chdir+0xbe/0x270 fs/open.c:554 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 ffff888055b7ae18 which belongs to the cache jfs_ip of size 2232 The buggy address is located 20 bytes to the right of allocated 2232-byte region [ffff888055b7ae18, ffff888055b7b6d0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55b78 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888076c20e01 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88814629fdc0 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff888076c20e01 head: 00fff00000000040 ffff88814629fdc0 dead000000000122 0000000000000000 head: 0000000000000000 00000000800d000d 00000000f5000000 ffff888076c20e01 head: 00fff00000000003 ffffea000156de01 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 8222, tgid 8221 (syz.3.701), ts 250914295974, free_ts 37713581245 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab mm/slub.c:2619 [inline] new_slab+0x23b/0x330 mm/slub.c:2673 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949 __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] kmem_cache_alloc_lru_noprof+0xf4/0x3b0 mm/slub.c:4216 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+0x6a8/0x1060 fs/jfs/super.c:511 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1679 vfs_get_tree+0x8e/0x340 fs/super.c:1802 do_new_mount fs/namespace.c:3885 [inline] path_mount+0x1414/0x2020 fs/namespace.c:4209 do_mount fs/namespace.c:4222 [inline] __do_sys_mount fs/namespace.c:4433 [inline] __se_sys_mount fs/namespace.c:4410 [inline] __x64_sys_mount+0x28d/0x310 fs/namespace.c:4410 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706 __free_pages mm/page_alloc.c:5071 [inline] free_contig_range+0x183/0x4b0 mm/page_alloc.c:6927 destroy_args+0x7f6/0xa60 mm/debug_vm_pgtable.c:1009 debug_vm_pgtable+0x13b8/0x2d00 mm/debug_vm_pgtable.c:1389 do_one_initcall+0x123/0x6e0 init/main.c:1274 do_initcall_level init/main.c:1336 [inline] do_initcalls init/main.c:1352 [inline] do_basic_setup init/main.c:1371 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1584 kernel_init+0x1c/0x2b0 init/main.c:1474 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888055b7b580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888055b7b600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888055b7b680: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff888055b7b700: fc fc fc fc fc fc fc fc fc fc 00 00 00 00 00 00 ffff888055b7b780: 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 loop3): txAbort: