================================================================== BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x10d4/0x31d0 fs/jfs/jfs_dtree.c:-1 Read of size 1 at addr ffff88806397c055 by task syz.0.363/6971 CPU: 0 PID: 6971 Comm: syz.0.363 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 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 dtSplitPage+0x10d4/0x31d0 fs/jfs/jfs_dtree.c:-1 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0xfb2/0x57a0 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x6e5/0xa70 fs/jfs/namei.c:270 vfs_mkdir+0x387/0x570 fs/namei.c:4073 do_mkdirat+0x1d7/0x5a0 fs/namei.c:4098 __do_sys_mkdirat fs/namei.c:4113 [inline] __se_sys_mkdirat fs/namei.c:4111 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111 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: 0033:0x7f8acfda5e97 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007f8ace00de68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f8ace00def0 RCX: 00007f8acfda5e97 RDX: 00000000000001ff RSI: 0000200000002080 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000002080 R13: 00007f8ace00deb0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6971: 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+0x1c2/0x380 fs/jfs/namei.c:1467 lookup_open fs/namei.c:3448 [inline] open_last_lookups fs/namei.c:3540 [inline] path_openat+0x1003/0x2f30 fs/namei.c:3747 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_creat fs/open.c:1347 [inline] __se_sys_creat fs/open.c:1341 [inline] __x64_sys_creat+0x8c/0xb0 fs/open.c:1341 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 The buggy address belongs to the object at ffff88806397b780 which belongs to the cache jfs_ip of size 2240 The buggy address is located 21 bytes to the right of 2240-byte region [ffff88806397b780, ffff88806397c040) The buggy address belongs to the page: page:ffffea00018e5e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x63978 head:ffffea00018e5e00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888065c75701 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888146679dc0 raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff888065c75701 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 4801, ts 82113090337, free_ts 63307609659 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 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+0x81e/0xdf0 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] new_inode_pseudo+0x5f/0x210 fs/inode.c:1001 new_inode+0x25/0x1c0 fs/inode.c:1030 ialloc+0x49/0x940 fs/jfs/jfs_inode.c:48 jfs_create+0x187/0xa50 fs/jfs/namei.c:92 lookup_open fs/namei.c:3470 [inline] open_last_lookups fs/namei.c:3540 [inline] path_openat+0x11e1/0x2f30 fs/namei.c:3747 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_creat fs/open.c:1347 [inline] __se_sys_creat fs/open.c:1341 [inline] __x64_sys_creat+0x8c/0xb0 fs/open.c:1341 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+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2020 [inline] discard_slab mm/slub.c:2026 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2512 put_cpu_partial+0x12d/0x190 mm/slub.c:2592 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 kmem_cache_zalloc include/linux/slab.h:728 [inline] __alloc_file+0x25/0x240 fs/file_table.c:132 alloc_empty_file+0x90/0x180 fs/file_table.c:181 alloc_file+0x5b/0x4f0 fs/file_table.c:223 alloc_file_pseudo+0x17a/0x1f0 fs/file_table.c:263 __shmem_file_setup+0x1cf/0x290 mm/shmem.c:4143 __do_sys_memfd_create mm/memfd.c:323 [inline] __se_sys_memfd_create+0x290/0x430 mm/memfd.c:266 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88806397bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806397bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806397c000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff88806397c080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88806397c100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================