================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x7e2/0xb90 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88807bade294 by task jfsCommit/116 CPU: 1 UID: 0 PID: 116 Comm: jfsCommit Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 jfs_lazycommit+0x7e2/0xb90 fs/jfs/jfs_txnmgr.c:2736 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5852: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4349 kmalloc_noprof include/linux/slab.h:902 [inline] kzalloc_noprof include/linux/slab.h:1036 [inline] jfs_fill_super+0xc2/0xd90 fs/jfs/super.c:452 get_tree_bdev_flags+0x490/0x5c0 fs/super.c:1636 vfs_get_tree+0x90/0x2b0 fs/super.c:1759 do_new_mount+0x2cf/0xb70 fs/namespace.c:3878 do_mount fs/namespace.c:4218 [inline] __do_sys_mount fs/namespace.c:4429 [inline] __se_sys_mount+0x38c/0x400 fs/namespace.c:4406 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5826: 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:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2376 [inline] slab_free mm/slub.c:4633 [inline] kfree+0x198/0x430 mm/slub.c:4832 generic_shutdown_super+0x139/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435 task_work_run+0x251/0x310 kernel/task_work.c:227 ptrace_notify+0x2dc/0x390 kernel/signal.c:2521 ptrace_report_syscall include/linux/ptrace.h:415 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] syscall_exit_work+0xc7/0x1d0 kernel/entry/common.c:173 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] syscall_exit_to_user_mode+0x24a/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807bade200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88807bade200, ffff88807bade300) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bade head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac41b40 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac41b40 dead000000000122 0000000000000000 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0001eeb781 ffffffffffffffff 0000000000000000 head: ffff888000000002 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5852, tgid 5848 (syz-executor166), ts 81977026744, free_ts 80817388139 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x368a/0x37d0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x2c5/0x7b0 mm/page_alloc.c:4740 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2446 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2610 new_slab mm/slub.c:2663 [inline] ___slab_alloc+0xc3b/0x1500 mm/slub.c:3849 __slab_alloc+0x58/0xa0 mm/slub.c:3939 __slab_alloc_node mm/slub.c:4014 [inline] slab_alloc_node mm/slub.c:4175 [inline] __do_kmalloc_node mm/slub.c:4317 [inline] __kmalloc_noprof+0x2ea/0x4d0 mm/slub.c:4330 kmalloc_noprof include/linux/slab.h:906 [inline] kmalloc_array_noprof include/linux/slab.h:945 [inline] __list_lru_init+0xab/0x5d0 mm/list_lru.c:581 alloc_super+0x839/0x9d0 fs/super.c:390 sget_fc+0x34c/0xa50 fs/super.c:760 sget_dev fs/super.c:1361 [inline] get_tree_bdev_flags+0x259/0x5c0 fs/super.c:1622 vfs_get_tree+0x90/0x2b0 fs/super.c:1759 do_new_mount+0x2cf/0xb70 fs/namespace.c:3878 do_mount fs/namespace.c:4218 [inline] __do_sys_mount fs/namespace.c:4429 [inline] __se_sys_mount+0x38c/0x400 fs/namespace.c:4406 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 page last free pid 5195 tgid 5195 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 discard_slab mm/slub.c:2707 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3176 put_cpu_partial+0x17e/0x250 mm/slub.c:3251 __slab_free+0x294/0x390 mm/slub.c:4503 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4138 [inline] slab_alloc_node mm/slub.c:4187 [inline] __kmalloc_cache_noprof+0x1c8/0x370 mm/slub.c:4344 kmalloc_noprof include/linux/slab.h:902 [inline] kzalloc_noprof include/linux/slab.h:1036 [inline] kernfs_iop_get_link+0x66/0x6b0 fs/kernfs/symlink.c:135 vfs_readlink+0x250/0x580 fs/namei.c:5332 do_readlinkat+0x241/0x380 fs/stat.c:578 __do_sys_readlink fs/stat.c:601 [inline] __se_sys_readlink fs/stat.c:598 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:598 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88807bade180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807bade200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807bade280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807bade300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807bade380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================