================================================================== BUG: KASAN: slab-use-after-free in memcmp+0x1b5/0x1c0 lib/string.c:681 Read of size 8 at addr ffff88816ee40500 by task syz-executor.4/4801 CPU: 0 PID: 4801 Comm: syz-executor.4 Not tainted 6.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x3d/0x60 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 memcmp+0x1b5/0x1c0 lib/string.c:681 memcmp include/linux/fortify-string.h:728 [inline] compare_mount_options fs/ceph/super.c:622 [inline] ceph_compare_super+0x10f/0x750 fs/ceph/super.c:1147 sget_fc+0x4ee/0x760 fs/super.c:764 ceph_get_tree+0x62c/0x16a0 fs/ceph/super.c:1232 vfs_get_tree+0x82/0x220 fs/super.c:1711 vfs_fsconfig_locked fs/fsopen.c:232 [inline] __do_sys_fsconfig+0x5d9/0xa80 fs/fsopen.c:439 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f9f5ea7cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9f5ddfe0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001af RAX: ffffffffffffffda RBX: 00007f9f5eb9bf80 RCX: 00007f9f5ea7cae9 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 RBP: 00007f9f5eac847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000006 R14: 00007f9f5eb9bf80 R15: 00007ffe88177ce8 Allocated by task 4785: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] ceph_init_fs_context+0xb9/0x510 fs/ceph/super.c:1333 alloc_fs_context+0x4bb/0x880 fs/fs_context.c:290 __do_sys_fsopen fs/fsopen.c:137 [inline] __se_sys_fsopen fs/fsopen.c:115 [inline] __x64_sys_fsopen+0xaa/0x180 fs/fsopen.c:115 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 4785: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15e/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1792 [inline] slab_free_freelist_hook+0x10b/0x1e0 mm/slub.c:1818 slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0xba/0x340 mm/slub.c:3814 destroy_fs_client+0x196/0x280 fs/ceph/super.c:860 deactivate_locked_super+0x83/0x270 fs/super.c:454 ceph_get_tree+0x1022/0x16a0 fs/ceph/super.c:1267 vfs_get_tree+0x82/0x220 fs/super.c:1711 vfs_fsconfig_locked fs/fsopen.c:232 [inline] __do_sys_fsconfig+0x5d9/0xa80 fs/fsopen.c:439 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88816ee40500 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of freed 96-byte region [ffff88816ee40500, ffff88816ee40560) The buggy address belongs to the physical page: page:ffffea0005bb9000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16ee40 flags: 0x100000000000200(slab|node=0|zone=2) page_type: 0xffffffff() raw: 0100000000000200 ffff888100041780 dead000000000122 0000000000000000 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4776, tgid 4773 (syz-executor.4), ts 77341143628, free_ts 77305078909 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x281/0x2f0 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x1131/0x3d90 mm/page_alloc.c:3221 __alloc_pages+0x1d0/0x470 mm/page_alloc.c:4477 alloc_slab_page mm/slub.c:1862 [inline] allocate_slab+0x24e/0x360 mm/slub.c:2009 new_slab mm/slub.c:2062 [inline] ___slab_alloc+0x7a7/0x1000 mm/slub.c:3215 __slab_alloc.constprop.0+0x4d/0x90 mm/slub.c:3314 __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x143/0x390 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc+0x4c/0x160 mm/slab_common.c:998 kmalloc_array include/linux/slab.h:619 [inline] ceph_msg_new2+0x2d2/0x460 net/ceph/messenger.c:1915 msgpool_alloc+0x9d/0x1b0 net/ceph/msgpool.c:17 mempool_init_node+0x29f/0x560 mm/mempool.c:207 mempool_create_node mm/mempool.c:276 [inline] mempool_create+0x75/0xb0 mm/mempool.c:261 ceph_msgpool_init+0xc6/0x180 net/ceph/msgpool.c:46 ceph_osdc_init+0x720/0xc10 net/ceph/osd_client.c:5189 ceph_create_client net/ceph/ceph_common.c:745 [inline] ceph_create_client+0x232/0x2e0 net/ceph/ceph_common.c:707 create_fs_client fs/ceph/super.c:781 [inline] ceph_get_tree+0x181/0x16a0 fs/ceph/super.c:1216 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1161 [inline] free_unref_page_prepare+0x5ac/0xcf0 mm/page_alloc.c:2348 free_unref_page_list+0xe6/0xaa0 mm/page_alloc.c:2489 release_pages+0x2a8/0x1040 mm/swap.c:1042 tlb_batch_pages_flush+0x79/0x140 mm/mmu_gather.c:97 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline] tlb_flush_mmu mm/mmu_gather.c:299 [inline] tlb_finish_mmu+0x114/0x5e0 mm/mmu_gather.c:391 exit_mmap+0x247/0x6f0 mm/mmap.c:3214 __mmput+0xb7/0x3e0 kernel/fork.c:1348 exit_mm kernel/exit.c:567 [inline] do_exit+0x776/0x2600 kernel/exit.c:861 do_group_exit+0xb4/0x250 kernel/exit.c:1024 get_signal+0x1ed5/0x1f00 kernel/signal.c:2877 arch_do_signal_or_restart+0x89/0x5f0 arch/x86/kernel/signal.c:308 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0xc3/0x150 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:297 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88816ee40400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88816ee40480: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc >ffff88816ee40500: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88816ee40580: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff88816ee40600: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================