================================================================== BUG: KASAN: slab-out-of-bounds in jfs_readdir+0x1989/0x3b40 fs/jfs/jfs_dtree.c:2905 Read of size 1 at addr ffff88804ecec055 by task syz.2.100/4862 CPU: 0 PID: 4862 Comm: syz.2.100 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 jfs_readdir+0x1989/0x3b40 fs/jfs/jfs_dtree.c:2905 iterate_dir+0x218/0x560 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xe5/0x260 fs/readdir.c:354 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: 0033:0x7fcf3978f749 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:00007fcf3a716038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007fcf399e5fa0 RCX: 00007fcf3978f749 RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 0000000000000006 RBP: 00007fcf39813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcf399e6038 R14: 00007fcf399e5fa0 R15: 00007ffc359d4888 The buggy address belongs to the object at ffff88804eceb780 which belongs to the cache jfs_ip of size 2240 The buggy address is located 21 bytes to the right of 2240-byte region [ffff88804eceb780, ffff88804ecec040) The buggy address belongs to the physical page: page:ffffea00013b3a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4ece8 head:ffffea00013b3a00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88807e415301 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8881462bc280 raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff88807e415301 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 4862, tgid 4861 (syz.2.100), ts 122553693285, free_ts 23707972482 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+0x2e/0x3f0 mm/page_alloc.c:3479 free_contig_range+0x9d/0x150 mm/page_alloc.c:9574 destroy_args+0x100/0xa31 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x32a/0x37e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x214/0x7a0 init/main.c:1310 do_initcall_level+0x137/0x1e4 init/main.c:1383 do_initcalls+0x4b/0x8a init/main.c:1399 kernel_init_freeable+0x3fa/0x5ac init/main.c:1638 kernel_init+0x19/0x1b0 init/main.c:1526 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88804ecebf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804ecebf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88804ecec000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88804ecec080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804ecec100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================