================================================================== BUG: KASAN: use-after-free in jfs_lazycommit+0x74f/0xa50 fs/jfs/jfs_txnmgr.c:2735 Read of size 4 at addr ffff8880278cce94 by task jfsCommit/108 CPU: 1 PID: 108 Comm: jfsCommit Not tainted 6.1.147-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x200 mm/kasan/report.c:418 kasan_report+0x10b/0x140 mm/kasan/report.c:522 jfs_lazycommit+0x74f/0xa50 fs/jfs/jfs_txnmgr.c:2735 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 5834: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] jfs_fill_super+0xd2/0xac0 fs/jfs/super.c:495 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3063 do_mount fs/namespace.c:3406 [inline] __do_sys_mount fs/namespace.c:3614 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3591 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 4274: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8880278cce00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of 256-byte region [ffff8880278cce00, ffff8880278ccf00) The buggy address belongs to the physical page: page:ffffea00009e3300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x278cc head:ffffea00009e3300 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017441b40 raw: 0000000000000000 0000000000100010 00000001ffffffff 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 0xd2000(__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 8987395844, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2115 alloc_slab_page+0x5d/0x160 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x87/0x2c0 mm/slub.c:1992 ___slab_alloc+0xbc6/0x1220 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3437 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] usb_string+0x10d/0x760 drivers/usb/core/message.c:979 usb_cache_string+0x7c/0x130 drivers/usb/core/message.c:1029 usb_enumerate_device drivers/usb/core/hub.c:2504 [inline] usb_new_device+0x360/0x1620 drivers/usb/core/hub.c:2629 register_root_hub+0x278/0x580 drivers/usb/core/hcd.c:1021 usb_add_hcd+0xa88/0xef0 drivers/usb/core/hcd.c:2995 vhci_hcd_probe+0x1bd/0x370 drivers/usb/usbip/vhci_hcd.c:1379 platform_probe+0x137/0x1c0 drivers/base/platform.c:1400 page_owner free stack trace missing Memory state around the buggy address: ffff8880278ccd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880278cce00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880278cce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880278ccf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880278ccf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================