================================================================== BUG: KASAN: slab-use-after-free in jfs_readdir+0x135b/0x4660 fs/jfs/jfs_dtree.c:2869 Read of size 8 at addr ffff888030ea4bd0 by task syz.3.585/10671 CPU: 0 UID: 0 PID: 10671 Comm: syz.3.585 Not tainted 6.11.0-rc7-syzkaller-00097-g196145c606d0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 jfs_readdir+0x135b/0x4660 fs/jfs/jfs_dtree.c:2869 wrap_directory_iterator+0x94/0xe0 fs/readdir.c:65 iterate_dir+0x57a/0x810 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:407 [inline] __se_sys_getdents64+0x20d/0x4f0 fs/readdir.c:392 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f397c57def9 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:00007f397bfde038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f397c736058 RCX: 00007f397c57def9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007f397c5f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f397c736058 R15: 00007ffc5718cbd8 Allocated by task 10671: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3992 [inline] slab_alloc_node mm/slub.c:4041 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4048 mempool_alloc_noprof+0x197/0x5a0 mm/mempool.c:402 alloc_metapage fs/jfs/jfs_metapage.c:182 [inline] __get_metapage+0x4ed/0xef0 fs/jfs/jfs_metapage.c:652 dtSplitRoot+0x2af/0x1930 fs/jfs/jfs_dtree.c:1909 dtSplitUp fs/jfs/jfs_dtree.c:992 [inline] dtInsert+0x12cd/0x6c10 fs/jfs/jfs_dtree.c:870 jfs_create+0x7ba/0xbb0 fs/jfs/namei.c:137 vfs_create+0x23c/0x3d0 fs/namei.c:3280 do_mknodat+0x447/0x5b0 fs/namei.c:4138 __do_sys_mknod fs/namei.c:4171 [inline] __se_sys_mknod fs/namei.c:4169 [inline] __x64_sys_mknod+0x8c/0xa0 fs/namei.c:4169 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 10671: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2256 [inline] slab_free mm/slub.c:4477 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4552 free_metapage fs/jfs/jfs_metapage.c:197 [inline] drop_metapage fs/jfs/jfs_metapage.c:234 [inline] release_metapage+0x725/0x960 fs/jfs/jfs_metapage.c:784 dtReadNext fs/jfs/jfs_dtree.c:3174 [inline] jfs_readdir+0x1025/0x4660 fs/jfs/jfs_dtree.c:2862 wrap_directory_iterator+0x94/0xe0 fs/readdir.c:65 iterate_dir+0x57a/0x810 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:407 [inline] __se_sys_getdents64+0x20d/0x4f0 fs/readdir.c:392 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888030ea4ba0 which belongs to the cache jfs_mp of size 184 The buggy address is located 48 bytes inside of freed 184-byte region [ffff888030ea4ba0, ffff888030ea4c58) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30ea4 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xfdffffff(slab) raw: 00fff00000000000 ffff88801fb378c0 ffffea0000c44740 0000000000000002 raw: 0000000000000000 0000000080100010 00000001fdffffff 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 0x1d2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5952, tgid 5952 (syz-executor), ts 148996353750, free_ts 148995952950 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500 prep_new_page mm/page_alloc.c:1508 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3446 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4702 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2325 allocate_slab+0x5a/0x2f0 mm/slub.c:2488 new_slab mm/slub.c:2541 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3727 __slab_alloc+0x58/0xa0 mm/slub.c:3817 __slab_alloc_node mm/slub.c:3870 [inline] slab_alloc_node mm/slub.c:4029 [inline] kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4048 mempool_alloc_noprof+0x197/0x5a0 mm/mempool.c:402 alloc_metapage fs/jfs/jfs_metapage.c:182 [inline] __get_metapage+0x4ed/0xef0 fs/jfs/jfs_metapage.c:652 diSync+0xc6/0x6e0 fs/jfs/jfs_imap.c:216 diUnmount+0xc7/0x130 fs/jfs/jfs_imap.c:185 jfs_umount+0x1fc/0x3a0 fs/jfs/jfs_umount.c:80 jfs_put_super+0x8a/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x136/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1696 page last free pid 5952 tgid 5952 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1101 [inline] free_unref_folios+0x100f/0x1ac0 mm/page_alloc.c:2667 folios_put_refs+0x76e/0x860 mm/swap.c:1039 folio_batch_release include/linux/pagevec.h:101 [inline] truncate_inode_pages_range+0x47b/0xfc0 mm/truncate.c:346 diUnmount+0xf2/0x130 fs/jfs/jfs_imap.c:190 jfs_umount+0x1c3/0x3a0 fs/jfs/jfs_umount.c:72 jfs_put_super+0x8a/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x136/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1696 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888030ea4a80: fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 ffff888030ea4b00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff888030ea4b80: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb ^ ffff888030ea4c00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888030ea4c80: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================