================================================================== BUG: KASAN: use-after-free in jfs_readdir+0x11ca/0x3c10 fs/jfs/jfs_dtree.c:3179 Read of size 8 at addr ffff888058cc4eb8 by task syz-executor/4717 CPU: 1 PID: 4717 Comm: syz-executor 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 jfs_readdir+0x11ca/0x3c10 fs/jfs/jfs_dtree.c:3179 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:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f90ec2180b3 Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 62 3d f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8 RSP: 002b:00007ffd0ab47f98 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 0000555572ee4600 RCX: 00007f90ec2180b3 RDX: 0000000000008000 RSI: 0000555572ee4600 RDI: 0000000000000005 RBP: 0000555572ee45d4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffa8 R13: 0000000000000010 R14: 0000555572ee45d0 R15: 00007ffd0ab4a250 Allocated by task 4717: 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 mempool_alloc+0x18f/0x4e0 mm/mempool.c:393 alloc_metapage fs/jfs/jfs_metapage.c:175 [inline] __get_metapage+0x5e8/0x1060 fs/jfs/jfs_metapage.c:652 dtReadFirst+0xd5/0x8f0 fs/jfs/jfs_dtree.c:3377 dtReadNext fs/jfs/jfs_dtree.c:3458 [inline] jfs_readdir+0x908/0x3c10 fs/jfs/jfs_dtree.c:3172 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:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 4717: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 free_metapage fs/jfs/jfs_metapage.c:190 [inline] drop_metapage fs/jfs/jfs_metapage.c:227 [inline] release_metapage+0x97b/0xe10 fs/jfs/jfs_metapage.c:758 dtReadNext fs/jfs/jfs_dtree.c:3500 [inline] jfs_readdir+0xf6f/0x3c10 fs/jfs/jfs_dtree.c:3172 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: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 ffff888058cc4e88 which belongs to the cache jfs_mp of size 184 The buggy address is located 48 bytes inside of 184-byte region [ffff888058cc4e88, ffff888058cc4f40) The buggy address belongs to the page: page:ffffea0001633100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x58cc4 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00008dd640 0000000200000002 ffff88801dc2c3c0 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x192800(GFP_NOWAIT|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4489, ts 68710561741, free_ts 68703654494 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 mempool_alloc+0x18f/0x4e0 mm/mempool.c:393 alloc_metapage fs/jfs/jfs_metapage.c:175 [inline] __get_metapage+0x5e8/0x1060 fs/jfs/jfs_metapage.c:652 diRead+0x6f7/0xbb0 fs/jfs/jfs_imap.c:367 jfs_iget+0x89/0x3f0 fs/jfs/inode.c:35 jfs_lookup+0x1c2/0x380 fs/jfs/namei.c:1467 __lookup_slow+0x27d/0x3d0 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+0x1e2/0x4f0 fs/namei.c:2492 user_path_at_empty+0x40/0x190 fs/namei.c:2891 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 __vunmap+0x8ab/0xa40 mm/vmalloc.c:2628 free_work+0x56/0x80 mm/vmalloc.c:95 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff888058cc4d80: fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888058cc4e00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc >ffff888058cc4e80: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888058cc4f00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888058cc4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================