================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff888063d14094 by task jfsCommit/114 CPU: 0 PID: 114 Comm: jfsCommit Not tainted 6.9.0-rc4-next-20240418-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5661: 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:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace_noprof+0x19c/0x2b0 mm/slub.c:4109 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] jfs_fill_super+0xff/0xc50 fs/jfs/super.c:495 mount_bdev+0x20a/0x2d0 fs/super.c:1659 legacy_get_tree+0xee/0x190 fs/fs_context.c:662 vfs_get_tree+0x90/0x2a0 fs/super.c:1780 do_new_mount+0x2be/0xb40 fs/namespace.c:3352 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5105: 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:2190 [inline] slab_free mm/slub.c:4393 [inline] kfree+0x149/0x350 mm/slub.c:4514 generic_shutdown_super+0x136/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1676 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24f/0x310 kernel/task_work.c:180 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+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888063d14000 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff888063d14000, ffff888063d14100) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x63d14 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffefff(slab) raw: 00fff80000000040 ffff888015041b40 ffffea0000b29500 0000000000000002 raw: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000 head: 00fff80000000040 ffff888015041b40 ffffea0000b29500 0000000000000002 head: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000 head: 00fff80000000001 ffffea00018f4501 ffffffffffffffff 0000000000000000 head: 0000000000000002 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 5106, tgid 1287134975 (syz-executor.1), ts 5106, free_ts 21730677485 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1476 prep_new_page mm/page_alloc.c:1484 [inline] get_page_from_freelist+0x2ce2/0x2d90 mm/page_alloc.c:3446 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4704 __alloc_pages_node_noprof include/linux/gfp.h:244 [inline] alloc_pages_node_noprof include/linux/gfp.h:271 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2259 allocate_slab+0x5a/0x2e0 mm/slub.c:2422 new_slab mm/slub.c:2475 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3624 __slab_alloc+0x58/0xa0 mm/slub.c:3714 __slab_alloc_node mm/slub.c:3767 [inline] slab_alloc_node mm/slub.c:3945 [inline] __do_kmalloc_node mm/slub.c:4077 [inline] __kmalloc_noprof+0x25e/0x400 mm/slub.c:4091 kmalloc_noprof include/linux/slab.h:664 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] new_dir fs/proc/proc_sysctl.c:953 [inline] get_subdir fs/proc/proc_sysctl.c:997 [inline] sysctl_mkdir_p fs/proc/proc_sysctl.c:1292 [inline] __register_sysctl_table+0xb53/0x1460 fs/proc/proc_sysctl.c:1373 __devinet_sysctl_register+0x1dc/0x2a0 net/ipv4/devinet.c:2589 devinet_init_net+0x32e/0x5d0 net/ipv4/devinet.c:2712 ops_init+0x352/0x610 net/core/net_namespace.c:136 setup_net+0x515/0xca0 net/core/net_namespace.c:340 copy_net_ns+0x4e4/0x7b0 net/core/net_namespace.c:505 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1096 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2609 free_contig_range+0x9e/0x160 mm/page_alloc.c:6663 destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1037 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1417 do_one_initcall+0x248/0x880 init/main.c:1263 do_initcall_level+0x157/0x210 init/main.c:1325 do_initcalls+0x3f/0x80 init/main.c:1341 kernel_init_freeable+0x435/0x5d0 init/main.c:1574 kernel_init+0x1d/0x2b0 init/main.c:1463 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff888063d13f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888063d14000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888063d14080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888063d14100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888063d14180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================