================================================================== BUG: KASAN: slab-use-after-free in get_fuse_conn_super fs/fuse/fuse_i.h:885 [inline] BUG: KASAN: slab-use-after-free in fuse_test_super+0x8c/0xa0 fs/fuse/inode.c:1689 Read of size 8 at addr ffff8880458e8580 by task syz-executor.0/19944 CPU: 0 PID: 19944 Comm: syz-executor.0 Not tainted 6.5.0-rc7-next-20230823-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+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 get_fuse_conn_super fs/fuse/fuse_i.h:885 [inline] fuse_test_super+0x8c/0xa0 fs/fuse/inode.c:1689 sget_fc+0x582/0x9b0 fs/super.c:778 fuse_get_tree+0x39a/0x640 fs/fuse/inode.c:1738 vfs_get_tree+0x8c/0x370 fs/super.c:1713 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 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: 0033:0x7f0335c7e1ea Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f03369fcee8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f03369fcf80 RCX: 00007f0335c7e1ea RDX: 0000000020000280 RSI: 0000000020000300 RDI: 0000000000000000 RBP: 0000000020000280 R08: 00007f03369fcf80 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000300 R13: 00007f03369fcf40 R14: 0000000000000000 R15: 00000000200028c0 Allocated by task 19940: 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:599 [inline] kzalloc include/linux/slab.h:720 [inline] fuse_get_tree+0xbe/0x640 fs/fuse/inode.c:1705 vfs_get_tree+0x8c/0x370 fs/super.c:1713 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 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 19940: 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+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 deactivate_locked_super+0xa0/0x2d0 fs/super.c:454 deactivate_super+0xde/0x100 fs/super.c:504 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:297 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880458e8580 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff8880458e8580, ffff8880458e85a0) The buggy address belongs to the physical page: page:ffffea0001163a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x458e8 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888012c41500 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000400040 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 0x12c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY), pid 5077, tgid 5077 (syz-executor.4), ts 117122656354, free_ts 25412410301 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1530 prep_new_page mm/page_alloc.c:1537 [inline] get_page_from_freelist+0x10d7/0x31b0 mm/page_alloc.c:3213 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4469 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2298 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8be/0x1570 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x137/0x350 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc+0x4f/0x100 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [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_number_perm+0x243/0x590 security/tomoyo/file.c:723 security_file_ioctl+0x72/0xb0 security/security.c:2647 __do_sys_ioctl fs/ioctl.c:865 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0xbb/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1130 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2342 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2435 free_contig_range+0xb6/0x190 mm/page_alloc.c:6385 destroy_args+0x768/0x990 mm/debug_vm_pgtable.c:1028 debug_vm_pgtable+0x1d7e/0x3e00 mm/debug_vm_pgtable.c:1408 do_one_initcall+0x117/0x630 init/main.c:1232 do_initcall_level init/main.c:1294 [inline] do_initcalls init/main.c:1310 [inline] do_basic_setup init/main.c:1329 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1547 kernel_init+0x1c/0x2a0 init/main.c:1437 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Memory state around the buggy address: ffff8880458e8480: 00 00 00 fc fc fc fc fc 00 00 00 00 fc fc fc fc ffff8880458e8500: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc >ffff8880458e8580: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff8880458e8600: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff8880458e8680: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================