================================================================== BUG: KASAN: use-after-free in cleancache_fs_enabled_mapping include/linux/cleancache.h:54 [inline] BUG: KASAN: use-after-free in cleancache_invalidate_page include/linux/cleancache.h:108 [inline] BUG: KASAN: use-after-free in unaccount_page_cache_page+0x6e6/0x750 mm/filemap.c:169 Read of size 4 at addr ffff8881b7858488 by task syz-executor.4/19552 CPU: 1 PID: 19552 Comm: syz-executor.4 Tainted: G W 5.4.233-syzkaller-00007-ge7141bb18b62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 cleancache_fs_enabled_mapping include/linux/cleancache.h:54 [inline] cleancache_invalidate_page include/linux/cleancache.h:108 [inline] unaccount_page_cache_page+0x6e6/0x750 mm/filemap.c:169 __delete_from_page_cache+0xd0/0x600 mm/filemap.c:237 __remove_mapping+0x4a2/0x590 mm/vmscan.c:978 shrink_page_list+0x22f9/0x42c0 mm/vmscan.c:1482 shrink_inactive_list+0x533/0xfe0 mm/vmscan.c:2001 shrink_list mm/vmscan.c:2293 [inline] shrink_node_memcg+0xc42/0x2430 mm/vmscan.c:2623 shrink_node+0x389/0x14a0 mm/vmscan.c:2836 shrink_zones mm/vmscan.c:3053 [inline] do_try_to_free_pages+0x63f/0x12b0 mm/vmscan.c:3111 try_to_free_mem_cgroup_pages+0x3f6/0x9b0 mm/vmscan.c:3412 memory_high_write+0x176/0x260 mm/memcontrol.c:6173 cgroup_file_write+0x275/0x5f0 kernel/cgroup/cgroup.c:3898 kernfs_fop_write+0x2e2/0x3e0 fs/kernfs/file.c:315 __vfs_write+0x103/0x750 fs/read_write.c:494 vfs_write+0x206/0x4e0 fs/read_write.c:558 ksys_write+0x199/0x2c0 fs/read_write.c:611 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Allocated by task 18320: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc_track_caller+0x100/0x2b0 mm/slub.c:4449 kmemdup+0x21/0x50 mm/util.c:127 ipv6_sysctl_net_init+0x2c/0x460 net/ipv6/sysctl_net_ipv6.c:210 ops_init+0x1d4/0x4a0 net/core/net_namespace.c:138 setup_net+0x214/0x990 net/core/net_namespace.c:345 copy_net_ns+0x30f/0x510 net/core/net_namespace.c:486 create_new_namespaces+0x47a/0x570 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0x119/0x170 kernel/nsproxy.c:202 ksys_unshare+0x544/0x990 kernel/fork.c:2901 __do_sys_unshare kernel/fork.c:2969 [inline] __se_sys_unshare kernel/fork.c:2967 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:2967 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 9: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kfree+0x123/0x370 mm/slub.c:4071 ipv6_sysctl_net_exit+0x164/0x190 net/ipv6/sysctl_net_ipv6.c:283 ops_exit_list net/core/net_namespace.c:179 [inline] cleanup_net+0x665/0xc90 net/core/net_namespace.c:609 process_one_work+0x765/0xd20 kernel/workqueue.c:2287 worker_thread+0xaef/0x1470 kernel/workqueue.c:2433 kthread+0x2da/0x360 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354 The buggy address belongs to the object at ffff8881b7858000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1160 bytes inside of 2048-byte region [ffff8881b7858000, ffff8881b7858800) The buggy address belongs to the page: page:ffffea0006de1600 refcount:1 mapcount:0 mapping:ffff8881f5c0c000 index:0xffff8881b785b000 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 ffffea0007ba8208 ffffea0007a0ce08 ffff8881f5c0c000 raw: ffff8881b785b000 0000000000080006 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc_trace+0x12d/0x260 mm/slub.c:2854 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] alloc_super+0x56/0x760 fs/super.c:203 sget+0x1f1/0x4d0 fs/super.c:613 mount_bdev+0xe4/0x340 fs/super.c:1390 legacy_get_tree+0xdf/0x170 fs/fs_context.c:647 vfs_get_tree+0x85/0x260 fs/super.c:1547 do_new_mount+0x292/0x570 fs/namespace.c:2843 do_mount+0x688/0xe10 fs/namespace.c:3163 ksys_mount+0xc2/0xf0 fs/namespace.c:3372 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4953 [inline] __free_pages+0x91/0x140 mm/page_alloc.c:4959 __free_slab+0x221/0x2e0 mm/slub.c:1774 __slab_free+0x34b/0x360 mm/slub.c:3012 qlist_free_all+0x43/0xb0 mm/kasan/quarantine.c:167 quarantine_reduce+0x1d9/0x210 mm/kasan/quarantine.c:260 __kasan_kmalloc+0x41/0x210 mm/kasan/common.c:507 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 getname_flags+0xb8/0x4e0 fs/namei.c:141 do_sys_open+0x357/0x810 fs/open.c:1107 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Memory state around the buggy address: ffff8881b7858380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881b7858400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881b7858480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881b7858500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881b7858580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================