================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x74b/0xa90 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88802ef94c94 by task jfsCommit/113 CPU: 0 UID: 0 PID: 113 Comm: jfsCommit Not tainted 6.16.0-rc2-syzkaller-00318-g739a6c93cc75 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 jfs_lazycommit+0x74b/0xa90 fs/jfs/jfs_txnmgr.c:2736 kthread+0x711/0x890 kernel/kthread.c:464 ret_from_fork+0x3f8/0x760 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6741: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] jfs_fill_super+0xc2/0xd90 fs/jfs/super.c:452 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1681 vfs_get_tree+0x92/0x290 fs/super.c:1804 do_new_mount+0x24a/0xa40 fs/namespace.c:3885 do_mount fs/namespace.c:4222 [inline] __do_sys_mount fs/namespace.c:4433 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4410 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 6390: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 generic_shutdown_super+0x135/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1755 deactivate_locked_super+0xbc/0x110 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x217/0x300 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff88802ef94c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88802ef94c00, ffff88802ef94d00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2ef94 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 ffff888019c41b40 ffffea0001f6a800 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff888019c41b40 ffffea0001f6a800 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0000bbe501 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 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 5891, tgid 5891 (syz-executor), ts 103920728367, free_ts 103858840522 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x2b37/0x2ce0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3a0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xc48/0x14d0 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] new_dir fs/proc/proc_sysctl.c:963 [inline] get_subdir fs/proc/proc_sysctl.c:1007 [inline] sysctl_mkdir_p fs/proc/proc_sysctl.c:1317 [inline] __register_sysctl_table+0xba1/0x1340 fs/proc/proc_sysctl.c:1392 __addrconf_sysctl_register+0x398/0x530 net/ipv6/addrconf.c:7248 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7296 ipv6_add_dev+0xd46/0x1360 net/ipv6/addrconf.c:458 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3654 notifier_call_chain+0x1b3/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] register_netdevice+0x1619/0x1af0 net/core/dev.c:11143 veth_newlink+0x5cc/0xa50 drivers/net/veth.c:1884 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3823 page last free pid 5891 tgid 5891 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc6f/0xe70 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x15f/0x1b0 mm/slub.c:3186 put_cpu_partial+0x17c/0x250 mm/slub.c:3261 __slab_free+0x2f7/0x400 mm/slub.c:4513 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4354 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4341 [inline] netdev_hold include/linux/netdevice.h:4370 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1973 [inline] netdev_queue_update_kobjects+0x1d1/0x6c0 net/core/net-sysfs.c:2035 register_queue_kobjects net/core/net-sysfs.c:2098 [inline] netdev_register_kobject+0x236/0x2f0 net/core/net-sysfs.c:2340 register_netdevice+0x1268/0x1af0 net/core/dev.c:11105 vxcan_newlink+0x383/0x570 drivers/net/can/vxcan.c:216 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3823 __rtnl_newlink net/core/rtnetlink.c:3940 [inline] rtnl_newlink+0x16d6/0x1c60 net/core/rtnetlink.c:4055 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944 Memory state around the buggy address: ffff88802ef94b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802ef94c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802ef94c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802ef94d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802ef94d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================