================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x4208/0x5de0 kernel/locking/lockdep.c:5004 Read of size 8 at addr ffff88805de6d020 by task syz-executor.1/10275 CPU: 0 PID: 10275 Comm: syz-executor.1 Not tainted 6.6.0-syzkaller-15029-gbe3ca57cfb77 #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 __lock_acquire+0x4208/0x5de0 kernel/locking/lockdep.c:5004 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 ptp_release+0xb2/0x2b0 drivers/ptp/ptp_chardev.c:146 ptp_read+0xf6/0x830 drivers/ptp/ptp_chardev.c:589 posix_clock_read+0x138/0x1b0 kernel/time/posix-clock.c:51 vfs_read+0x1ce/0x8f0 fs/read_write.c:468 ksys_read+0x12f/0x250 fs/read_write.c:613 do_syscall_32_irqs_on arch/x86/entry/common.c:164 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:230 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a RIP: 0023:0xf7f35579 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:00000000f7f0f5ac EFLAGS: 00000292 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000 RDX: 0000000000000019 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10274: 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:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 do_sys_open fs/open.c:1455 [inline] __do_compat_sys_openat fs/open.c:1515 [inline] __se_compat_sys_openat fs/open.c:1513 [inline] __ia32_compat_sys_openat+0x16e/0x200 fs/open.c:1513 do_syscall_32_irqs_on arch/x86/entry/common.c:164 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:230 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a Freed by task 10274: 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+0xc0/0x180 mm/slub.c:3822 ptp_release+0x204/0x2b0 drivers/ptp/ptp_chardev.c:150 ptp_read+0xf6/0x830 drivers/ptp/ptp_chardev.c:589 posix_clock_read+0x138/0x1b0 kernel/time/posix-clock.c:51 vfs_read+0x1ce/0x8f0 fs/read_write.c:468 ksys_read+0x12f/0x250 fs/read_write.c:613 do_syscall_32_irqs_on arch/x86/entry/common.c:164 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:230 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:255 entry_SYSENTER_compat_after_hwframe+0x70/0x7a The buggy address belongs to the object at ffff88805de6c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 4128 bytes inside of freed 8192-byte region [ffff88805de6c000, ffff88805de6e000) The buggy address belongs to the physical page: page:ffffea0001779a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5de68 head:ffffea0001779a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x4fff00000000840(slab|head|node=1|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 04fff00000000840 ffff888013043180 ffffea00018daa00 dead000000000005 raw: 0000000000000000 0000000000020002 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 10194, tgid 10192 (syz-executor.3), ts 80951940809, free_ts 80884141799 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 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+0x8c7/0x1580 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+0x131/0x310 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] ptp_open+0xe3/0x4f0 drivers/ptp/ptp_chardev.c:112 posix_clock_open+0x17e/0x240 kernel/time/posix-clock.c:134 chrdev_open+0x26d/0x6e0 fs/char_dev.c:414 do_dentry_open+0x8d4/0x18d0 fs/open.c:948 do_open fs/namei.c:3622 [inline] path_openat+0x1d4e/0x2c40 fs/namei.c:3779 do_filp_open+0x1de/0x430 fs/namei.c:3809 do_sys_openat2+0x176/0x1e0 fs/open.c:1440 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1286 [inline] nlmsg_new include/net/netlink.h:1010 [inline] ctrl_build_family_msg+0x36/0xa0 net/netlink/genetlink.c:1243 ctrl_getfamily+0x355/0x540 net/netlink/genetlink.c:1323 genl_family_rcv_msg_doit+0x1fc/0x2e0 net/netlink/genetlink.c:972 genl_family_rcv_msg net/netlink/genetlink.c:1052 [inline] genl_rcv_msg+0x561/0x800 net/netlink/genetlink.c:1067 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1368 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910 Memory state around the buggy address: ffff88805de6cf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805de6cf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805de6d000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805de6d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805de6d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- 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