================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:400 [inline] BUG: KASAN: slab-use-after-free in __refcount_sub_and_test include/linux/refcount.h:264 [inline] BUG: KASAN: slab-use-after-free in __refcount_dec_and_test include/linux/refcount.h:307 [inline] BUG: KASAN: slab-use-after-free in refcount_dec_and_test include/linux/refcount.h:325 [inline] BUG: KASAN: slab-use-after-free in p9_fid_put include/net/9p/client.h:275 [inline] BUG: KASAN: slab-use-after-free in v9fs_free_request+0x7d/0x110 fs/9p/vfs_addr.c:128 Write of size 4 at addr ffff88802b2d638c by task kworker/u32:1/12 CPU: 2 PID: 12 Comm: kworker/u32:1 Not tainted 6.9.0-rc6-syzkaller-00053-g0106679839f7 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Workqueue: events_unbound v9fs_upload_to_server_worker 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 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:400 [inline] __refcount_sub_and_test include/linux/refcount.h:264 [inline] __refcount_dec_and_test include/linux/refcount.h:307 [inline] refcount_dec_and_test include/linux/refcount.h:325 [inline] p9_fid_put include/net/9p/client.h:275 [inline] v9fs_free_request+0x7d/0x110 fs/9p/vfs_addr.c:128 netfs_free_request+0x22f/0x6b0 fs/netfs/objects.c:97 netfs_put_request+0x19b/0x1f0 fs/netfs/objects.c:130 netfs_free_subrequest fs/netfs/objects.c:178 [inline] netfs_put_subrequest+0x408/0x6c0 fs/netfs/objects.c:192 v9fs_upload_to_server fs/9p/vfs_addr.c:36 [inline] v9fs_upload_to_server_worker+0x18c/0x3b0 fs/9p/vfs_addr.c:44 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3267 process_scheduled_works kernel/workqueue.c:3348 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3429 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 12110: 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] p9_fid_create+0x45/0x470 net/9p/client.c:853 p9_client_walk+0xc6/0x550 net/9p/client.c:1154 clone_fid fs/9p/fid.h:23 [inline] v9fs_fid_clone fs/9p/fid.h:33 [inline] v9fs_file_open+0x5b5/0xae0 fs/9p/vfs_file.c:56 do_dentry_open+0x8da/0x18c0 fs/open.c:955 do_open fs/namei.c:3642 [inline] path_openat+0x1dfb/0x2990 fs/namei.c:3799 do_filp_open+0x1dc/0x430 fs/namei.c:3826 file_open_name+0x2a4/0x450 fs/open.c:1351 acct_on+0x77/0x790 kernel/acct.c:226 __do_sys_acct kernel/acct.c:305 [inline] __se_sys_acct kernel/acct.c:292 [inline] __x64_sys_acct+0xad/0x220 kernel/acct.c:292 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 Freed by task 9315: 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 p9_client_destroy+0x14c/0x480 net/9p/client.c:1070 v9fs_session_close+0x49/0x2d0 fs/9p/v9fs.c:506 v9fs_kill_super+0x4d/0xa0 fs/9p/vfs_super.c:196 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_syscall_64+0xdc/0x260 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802b2d6380 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 12 bytes inside of freed 96-byte region [ffff88802b2d6380, ffff88802b2d63e0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b2d6 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888015042780 ffffea0000aad340 dead000000000006 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5198, tgid 75940509 (syz-executor.1), ts 5198, free_ts 51585699079 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+0x66d/0x1790 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+0x3b4/0x440 mm/slub.c:3979 kmalloc include/linux/slab.h:632 [inline] kzalloc include/linux/slab.h:749 [inline] tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x19d/0x720 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x273/0x450 security/tomoyo/file.c:822 tomoyo_path_unlink+0x92/0xe0 security/tomoyo/tomoyo.c:162 security_path_unlink+0x100/0x170 security/security.c:1857 do_unlinkat+0x55b/0x750 fs/namei.c:4396 __do_sys_unlink fs/namei.c:4447 [inline] __se_sys_unlink fs/namei.c:4445 [inline] __x64_sys_unlink+0xc7/0x110 fs/namei.c:4445 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 page last free pid 5198 tgid 5198 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 __put_partials+0x14c/0x170 mm/slub.c:2906 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+0x136/0x320 mm/slub.c:3852 vm_area_dup+0x21/0x2f0 kernel/fork.c:482 dup_mmap kernel/fork.c:697 [inline] dup_mm kernel/fork.c:1688 [inline] copy_mm kernel/fork.c:1737 [inline] copy_process+0x7b27/0x9090 kernel/fork.c:2390 kernel_clone+0xfd/0x980 kernel/fork.c:2797 __do_sys_clone+0xba/0x100 kernel/fork.c:2940 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: ffff88802b2d6280: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff88802b2d6300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff88802b2d6380: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88802b2d6400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88802b2d6480: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================