================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x11c/0x7f70 kernel/locking/lockdep.c:5004 Read of size 8 at addr ffff88807e705020 by task syz-executor.4/17679 CPU: 1 PID: 17679 Comm: syz-executor.4 Not tainted 6.6.0-syzkaller-06824-g8bc9e6515183 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 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 __lock_acquire+0x11c/0x7f70 kernel/locking/lockdep.c:5004 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 ptp_release+0x96/0x1e0 drivers/ptp/ptp_chardev.c:146 ptp_read+0x17f/0x820 drivers/ptp/ptp_chardev.c:589 posix_clock_read+0x12f/0x190 kernel/time/posix-clock.c:51 vfs_read+0x289/0xb00 fs/read_write.c:468 ksys_read+0x1a0/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f7f0947cae9 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:00007f7f0a12f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f7f0959bf80 RCX: 00007f7f0947cae9 RDX: 0000000000000099 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00007f7f094c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f7f0959bf80 R15: 00007ffe947d2248 Allocated by task 17679: 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:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xd9/0x430 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x155/0x1f0 kernel/time/posix-clock.c:134 chrdev_open+0x5ab/0x630 fs/char_dev.c:414 do_dentry_open+0x8fd/0x1590 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x2845/0x3280 fs/namei.c:3779 do_filp_open+0x234/0x490 fs/namei.c:3809 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_sys_openat fs/open.c:1471 [inline] __se_sys_openat fs/open.c:1466 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1466 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 17680: 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:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x263/0x3a0 mm/slub.c:3822 ptp_release+0x1ce/0x1e0 drivers/ptp/ptp_chardev.c:150 ptp_read+0x17f/0x820 drivers/ptp/ptp_chardev.c:589 posix_clock_read+0x12f/0x190 kernel/time/posix-clock.c:51 vfs_read+0x289/0xb00 fs/read_write.c:468 ksys_read+0x1a0/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88807e704000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 4128 bytes inside of freed 8192-byte region [ffff88807e704000, ffff88807e706000) The buggy address belongs to the physical page: page:ffffea0001f9c000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e700 head:ffffea0001f9c000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012c42280 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080020002 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), pid 17676, tgid 17671 (syz-executor.1), ts 817673013116, free_ts 817617354852 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31db/0x3360 mm/page_alloc.c:3170 __alloc_pages+0x255/0x670 mm/page_alloc.c:4426 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xc85/0x1310 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3517 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xd9/0x430 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x155/0x1f0 kernel/time/posix-clock.c:134 chrdev_open+0x5ab/0x630 fs/char_dev.c:414 do_dentry_open+0x8fd/0x1590 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x2845/0x3280 fs/namei.c:3779 do_filp_open+0x234/0x490 fs/namei.c:3809 do_sys_openat2+0x13e/0x1d0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_sys_openat fs/open.c:1471 [inline] __se_sys_openat fs/open.c:1466 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1466 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 __slab_free+0x2f6/0x390 mm/slub.c:3715 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 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:188 [inline] slab_post_alloc_hook+0x67/0x3d0 mm/slab.h:762 slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x104/0x2c0 mm/slub.c:3502 vma_lock_alloc kernel/fork.c:459 [inline] vm_area_dup+0x61/0x280 kernel/fork.c:512 dup_mmap kernel/fork.c:710 [inline] dup_mm kernel/fork.c:1684 [inline] copy_mm+0xcea/0x1f10 kernel/fork.c:1733 copy_process+0x1d73/0x4170 kernel/fork.c:2499 kernel_clone+0x222/0x840 kernel/fork.c:2907 __do_sys_clone kernel/fork.c:3050 [inline] __se_sys_clone kernel/fork.c:3034 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:3034 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Memory state around the buggy address: ffff88807e704f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e704f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807e705000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e705080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e705100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================