================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x65c/0x9c8 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff0000cbf08294 by task jfsCommit/100 CPU: 0 UID: 0 PID: 100 Comm: jfsCommit Not tainted 6.15.0-rc2-syzkaller-gc72692105976 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x198/0x550 mm/kasan/report.c:521 kasan_report+0xd8/0x138 mm/kasan/report.c:634 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380 jfs_lazycommit+0x65c/0x9c8 fs/jfs/jfs_txnmgr.c:2736 kthread+0x674/0x7dc kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 Allocated by task 8431: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:562 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x2cc/0x428 mm/slub.c:4362 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] jfs_fill_super+0xc0/0xba0 fs/jfs/super.c:452 get_tree_bdev_flags+0x38c/0x494 fs/super.c:1636 get_tree_bdev+0x2c/0x3c fs/super.c:1659 jfs_get_tree+0x28/0x38 fs/jfs/super.c:635 vfs_get_tree+0x90/0x28c fs/super.c:1759 do_new_mount+0x278/0x900 fs/namespace.c:3879 path_mount+0x590/0xe04 fs/namespace.c:4206 do_mount fs/namespace.c:4219 [inline] __do_sys_mount fs/namespace.c:4430 [inline] __se_sys_mount fs/namespace.c:4407 [inline] __arm64_sys_mount+0x4f4/0x5d0 fs/namespace.c:4407 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Freed by task 7816: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x64/0x8c mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kfree+0x180/0x478 mm/slub.c:4845 jfs_put_super+0x144/0x188 fs/jfs/super.c:203 generic_shutdown_super+0x12c/0x2bc fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xc4/0x12c fs/super.c:473 deactivate_super+0xe0/0x100 fs/super.c:506 cleanup_mnt+0x34c/0x3dc fs/namespace.c:1435 __cleanup_mnt+0x20/0x30 fs/namespace.c:1442 task_work_run+0x230/0x2e0 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] do_notify_resume+0x178/0x1f4 arch/arm64/kernel/entry-common.c:151 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:745 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 The buggy address belongs to the object at ffff0000cbf08200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff0000cbf08200, ffff0000cbf08300) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10bf08 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000040 ffff0000c0001b40 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 05ffc00000000040 ffff0000c0001b40 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 05ffc00000000001 fffffdffc32fc201 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000cbf08180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000cbf08200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000cbf08280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000cbf08300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000cbf08380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================