================================================================== BUG: KASAN: slab-use-after-free in memcmp lib/string.c:681 [inline] BUG: KASAN: slab-use-after-free in bcmp+0x113/0x1e0 lib/string.c:713 Read of size 8 at addr ffff8880163e8500 by task syz-executor.1/5466 CPU: 0 PID: 5466 Comm: syz-executor.1 Not tainted 6.5.0-syzkaller-01810-gf97e18a3f2fb #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+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 memcmp lib/string.c:681 [inline] bcmp+0x113/0x1e0 lib/string.c:713 compare_mount_options fs/ceph/super.c:622 [inline] ceph_compare_super+0x107/0x7a0 fs/ceph/super.c:1147 sget_fc+0x145/0x750 fs/super.c:778 ceph_get_tree+0x74f/0x13d0 fs/ceph/super.c:1232 vfs_get_tree+0x8c/0x280 fs/super.c:1711 vfs_cmd_create+0xe4/0x230 fs/fsopen.c:230 __do_sys_fsconfig fs/fsopen.c:475 [inline] __se_sys_fsconfig+0x8c3/0xe00 fs/fsopen.c:349 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6eea47cae9 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:00007f6eeb1960c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001af RAX: ffffffffffffffda RBX: 00007f6eea59c050 RCX: 00007f6eea47cae9 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 RBP: 00007f6eea4c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f6eea59c050 R15: 00007ffdc4d20b68 Allocated by task 5447: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] ceph_init_fs_context+0xc9/0x4a0 fs/ceph/super.c:1333 alloc_fs_context+0x697/0x830 fs/fs_context.c:294 __do_sys_fsopen fs/fsopen.c:137 [inline] __se_sys_fsopen+0x9f/0x2c0 fs/fsopen.c:115 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5447: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1792 [inline] slab_free_freelist_hook mm/slub.c:1818 [inline] slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3814 destroy_fs_client+0x172/0x200 fs/ceph/super.c:860 deactivate_locked_super+0xa5/0x200 fs/super.c:454 ceph_get_tree+0x985/0x13d0 fs/ceph/super.c:1267 vfs_get_tree+0x8c/0x280 fs/super.c:1711 vfs_cmd_create+0xe4/0x230 fs/fsopen.c:230 __do_sys_fsconfig fs/fsopen.c:475 [inline] __se_sys_fsconfig+0x8c3/0xe00 fs/fsopen.c:349 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880163e8500 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of freed 96-byte region [ffff8880163e8500, ffff8880163e8560) The buggy address belongs to the physical page: page:ffffea000058fa00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x163e8 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000200 ffff888012841780 dead000000000100 dead000000000122 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 0x112820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 8, tgid 8 (kworker/0:1), ts 126011564001, free_ts 125982949235 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x31e8/0x3370 mm/page_alloc.c:3221 __alloc_pages+0x255/0x670 mm/page_alloc.c:4477 alloc_slab_page+0x6a/0x160 mm/slub.c:1862 allocate_slab mm/slub.c:2009 [inline] new_slab+0x84/0x2f0 mm/slub.c:2062 ___slab_alloc+0xade/0x1100 mm/slub.c:3215 __slab_alloc mm/slub.c:3314 [inline] __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3509 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1076 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:990 [inline] nsim_fib_event_nb+0x17c/0x10b0 drivers/net/netdevsim/fib.c:1043 notifier_call_chain+0x18c/0x3a0 kernel/notifier.c:93 atomic_notifier_call_chain+0xb6/0x150 kernel/notifier.c:231 call_fib_notifiers+0x31/0x60 net/core/fib_notifier.c:35 call_fib6_entry_notifiers net/ipv6/ip6_fib.c:401 [inline] fib6_add_rt2node net/ipv6/ip6_fib.c:1223 [inline] fib6_add+0x1b78/0x3d40 net/ipv6/ip6_fib.c:1477 __ip6_ins_rt net/ipv6/route.c:1301 [inline] ip6_ins_rt+0x106/0x170 net/ipv6/route.c:1311 __ipv6_ifa_notify+0x5c0/0x11d0 net/ipv6/addrconf.c:6168 ipv6_ifa_notify net/ipv6/addrconf.c:6207 [inline] addrconf_dad_completed+0x181/0xd10 net/ipv6/addrconf.c:4219 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+0x903/0xa30 mm/page_alloc.c:2348 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2443 __slab_free+0x2f6/0x390 mm/slub.c:3707 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook+0x6c/0x3b0 mm/slab.h:762 slab_alloc_node mm/slub.c:3470 [inline] __kmem_cache_alloc_node+0x141/0x270 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:998 kmalloc include/linux/slab.h:586 [inline] kernfs_fop_write_iter+0x15b/0x4f0 fs/kernfs/file.c:311 call_write_iter include/linux/fs.h:1985 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x782/0xaf0 fs/read_write.c:584 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880163e8400: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880163e8480: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc >ffff8880163e8500: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8880163e8580: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880163e8600: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ==================================================================