================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88805a617294 by task jfsCommit/136 CPU: 1 PID: 136 Comm: jfsCommit Not tainted 6.9.0-rc4-syzkaller-00038-g8cd26fd90c1a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 6143: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387 kmalloc include/linux/slab.h:628 [inline] kzalloc include/linux/slab.h:749 [inline] jfs_fill_super+0xe5/0xd20 fs/jfs/super.c:495 mount_bdev+0x1e3/0x2d0 fs/super.c:1658 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8f/0x380 fs/super.c:1779 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 5204: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kfree+0x129/0x390 mm/slub.c:4390 generic_shutdown_super+0x159/0x3d0 fs/super.c:641 kill_block_super+0x3b/0x90 fs/super.c:1675 deactivate_locked_super+0xbe/0x1a0 fs/super.c:472 deactivate_super+0xde/0x100 fs/super.c:505 cleanup_mnt+0x222/0x450 fs/namespace.c:1267 task_work_run+0x14e/0x250 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+0x278/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x82/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff88805a617200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88805a617200, ffff88805a617300) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5a616 head: order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff80000000840(slab|head|node=1|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 04fff80000000840 ffff888014c42b40 ffffea0001794600 dead000000000004 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 04fff80000000840 ffff888014c42b40 ffffea0001794600 dead000000000004 head: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 head: 04fff80000000001 ffffea0001698581 dead000000000122 00000000ffffffff head: 0000000200000000 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5320, tgid 5318 (syz-executor.1), ts 57144524368, free_ts 57119347828 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2175 [inline] allocate_slab mm/slub.c:2338 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2391 ___slab_alloc+0x670/0x16d0 mm/slub.c:3525 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610 __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] __do_kmalloc_node mm/slub.c:3965 [inline] __kmalloc_node+0x36e/0x480 mm/slub.c:3973 kmalloc_array_node include/linux/slab.h:726 [inline] kcalloc_node include/linux/slab.h:731 [inline] memcg_alloc_slab_cgroups+0xa9/0x180 mm/memcontrol.c:3015 __memcg_slab_post_alloc_hook+0xa3/0x370 mm/slub.c:1960 memcg_slab_post_alloc_hook mm/slub.c:1983 [inline] slab_post_alloc_hook mm/slub.c:3807 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_lru+0x397/0x6f0 mm/slub.c:3864 alloc_inode_sb include/linux/fs.h:3091 [inline] alloc_inode+0xba/0x230 fs/inode.c:263 new_inode_pseudo fs/inode.c:1007 [inline] new_inode+0x22/0x270 fs/inode.c:1033 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x11a/0x620 fs/debugfs/inode.c:437 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:1150 [inline] kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1281 [inline] kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:5460 [inline] kvm_dev_ioctl+0x1851/0x1c60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:5502 __do_compat_sys_ioctl+0x2c3/0x330 fs/ioctl.c:1004 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:321 page last free pid 5184 tgid 5184 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3888 __alloc_skb+0x2b3/0x380 net/core/skbuff.c:658 alloc_skb_fclone include/linux/skbuff.h:1363 [inline] tcp_stream_alloc_skb+0x34/0x570 net/ipv4/tcp.c:873 tcp_sendmsg_locked+0xed5/0x3470 net/ipv4/tcp.c:1155 tcp_sendmsg+0x2e/0x50 net/ipv4/tcp.c:1342 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4b8/0x5c0 net/socket.c:1160 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6db/0x1100 fs/read_write.c:590 ksys_write+0x1f8/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805a617180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805a617200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805a617280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805a617300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805a617380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================