================================================================== BUG: KASAN: slab-use-after-free in memcmp+0x1b5/0x1c0 lib/string.c:681 Read of size 8 at addr ffff8880008b2f80 by task syz-executor.0/9053 CPU: 0 PID: 9053 Comm: syz-executor.0 Not tainted 6.5.0-syzkaller-00607-g42a7f6e3ffe0 #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+0xd9/0x1b0 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+0x11a/0x8d0 fs/ceph/super.c:1147 sget_fc+0x582/0x9b0 fs/super.c:778 ceph_get_tree+0x6ea/0x1910 fs/ceph/super.c:1232 vfs_get_tree+0x8c/0x370 fs/super.c:1711 vfs_cmd_create+0x11f/0x2f0 fs/fsopen.c:230 vfs_fsconfig_locked fs/fsopen.c:294 [inline] __do_sys_fsconfig+0x832/0xb90 fs/fsopen.c:475 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f4c579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f475ac EFLAGS: 00000292 ORIG_RAX: 00000000000001af RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 9030: 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+0xc8/0x530 fs/ceph/super.c:1333 alloc_fs_context+0x56c/0x9f0 fs/fs_context.c:294 __do_sys_fsopen fs/fsopen.c:137 [inline] __se_sys_fsopen fs/fsopen.c:115 [inline] __ia32_sys_fsopen+0xef/0x230 fs/fsopen.c:115 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Freed by task 9030: 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+0xb8/0x2f0 mm/slub.c:3814 destroy_mount_options fs/ceph/super.c:599 [inline] destroy_mount_options+0xe9/0x140 fs/ceph/super.c:588 destroy_fs_client+0x1b6/0x2b0 fs/ceph/super.c:860 deactivate_locked_super+0xa0/0x2d0 fs/super.c:454 ceph_get_tree+0x1270/0x1910 fs/ceph/super.c:1267 vfs_get_tree+0x8c/0x370 fs/super.c:1711 vfs_cmd_create+0x11f/0x2f0 fs/fsopen.c:230 vfs_fsconfig_locked fs/fsopen.c:294 [inline] __do_sys_fsconfig+0x832/0xb90 fs/fsopen.c:475 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3372 cfg80211_update_known_bss+0x821/0xa80 net/wireless/scan.c:1744 __cfg80211_bss_update+0x1ba/0x2540 net/wireless/scan.c:1788 cfg80211_inform_single_bss_frame_data+0x7e7/0xf30 net/wireless/scan.c:2881 cfg80211_inform_bss_frame_data+0xbf/0x290 net/wireless/scan.c:2912 ieee80211_bss_info_update+0x37b/0x9a0 net/mac80211/scan.c:211 ieee80211_rx_bss_info net/mac80211/ibss.c:1124 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x195f/0x2ee0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1604 [inline] ieee80211_iface_work+0xa1f/0xd40 net/mac80211/iface.c:1658 cfg80211_wiphy_work+0x24e/0x330 net/wireless/core.c:435 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3372 cfg80211_update_known_bss+0x821/0xa80 net/wireless/scan.c:1744 __cfg80211_bss_update+0x1ba/0x2540 net/wireless/scan.c:1788 cfg80211_inform_single_bss_frame_data+0x7e7/0xf30 net/wireless/scan.c:2881 cfg80211_inform_bss_frame_data+0xbf/0x290 net/wireless/scan.c:2912 ieee80211_bss_info_update+0x37b/0x9a0 net/mac80211/scan.c:211 ieee80211_rx_bss_info net/mac80211/ibss.c:1124 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x195f/0x2ee0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1604 [inline] ieee80211_iface_work+0xa1f/0xd40 net/mac80211/iface.c:1658 cfg80211_wiphy_work+0x24e/0x330 net/wireless/core.c:435 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600 worker_thread+0x687/0x1110 kernel/workqueue.c:2751 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 The buggy address belongs to the object at ffff8880008b2f80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of freed 96-byte region [ffff8880008b2f80, ffff8880008b2fe0) The buggy address belongs to the physical page: page:ffffea0000022c80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8b2 flags: 0x7ff00000000200(slab|node=0|zone=0|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 007ff00000000200 ffff888012842780 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 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5172, tgid 5172 (syz-executor.1), ts 207076360605, free_ts 185279785753 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d2/0x350 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x10a9/0x31e0 mm/page_alloc.c:3221 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4477 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1862 [inline] allocate_slab+0x24e/0x380 mm/slub.c:2009 new_slab mm/slub.c:2062 [inline] ___slab_alloc+0x8bc/0x1570 mm/slub.c:3215 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3314 __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x137/0x350 mm/slub.c:3509 __do_kmalloc_node mm/slab_common.c:984 [inline] __kmalloc+0x4c/0x100 mm/slab_common.c:998 kmalloc include/linux/slab.h:586 [inline] kzalloc include/linux/slab.h:703 [inline] tomoyo_encode2+0x100/0x3d0 security/tomoyo/realpath.c:45 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x196/0x710 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x271/0x450 security/tomoyo/file.c:822 security_inode_getattr+0xf1/0x150 security/security.c:2128 vfs_getattr fs/stat.c:206 [inline] vfs_statx+0x180/0x430 fs/stat.c:281 do_statx+0xf0/0x170 fs/stat.c:698 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+0x508/0xb90 mm/page_alloc.c:2348 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2443 __folio_put_small mm/swap.c:106 [inline] __folio_put+0xc5/0x140 mm/swap.c:129 folio_put include/linux/mm.h:1440 [inline] put_page include/linux/mm.h:1509 [inline] free_page_and_swap_cache+0x25a/0x2d0 mm/swap_state.c:304 __tlb_remove_table arch/x86/include/asm/tlb.h:34 [inline] __tlb_remove_table_free mm/mmu_gather.c:153 [inline] tlb_remove_table_rcu+0x89/0xe0 mm/mmu_gather.c:208 rcu_do_batch kernel/rcu/tree.c:2139 [inline] rcu_core+0x7fb/0x1bb0 kernel/rcu/tree.c:2403 __do_softirq+0x218/0x965 kernel/softirq.c:553 Memory state around the buggy address: ffff8880008b2e80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff8880008b2f00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8880008b2f80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8880008b3000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880008b3080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi