================================================================== BUG: KASAN: slab-out-of-bounds in strcmp+0x96/0xb0 lib/string.c:328 Read of size 1 at addr ffff8801c3006601 by task syz-executor6/10338 CPU: 0 PID: 10338 Comm: syz-executor6 Not tainted 4.15.0-rc2+ #119 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427 strcmp+0x96/0xb0 lib/string.c:328 security_context_to_sid_core+0x437/0x620 security/selinux/ss/services.c:1420 security_context_to_sid+0x32/0x40 security/selinux/ss/services.c:1479 selinux_setprocattr+0x51c/0xb50 security/selinux/hooks.c:5985 security_setprocattr+0x85/0xc0 security/security.c:1264 proc_pid_attr_write+0x1e6/0x280 fs/proc/base.c:2545 __vfs_write+0xef/0x970 fs/read_write.c:480 __kernel_write+0xfe/0x350 fs/read_write.c:501 write_pipe_buf+0x175/0x220 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x328/0x730 fs/splice.c:626 splice_from_pipe+0x1e9/0x330 fs/splice.c:661 default_file_splice_write+0x40/0x90 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x125/0x180 fs/splice.c:1018 splice_direct_to_actor+0x2c1/0x820 fs/splice.c:973 do_splice_direct+0x2a7/0x3d0 fs/splice.c:1061 do_sendfile+0x5d5/0xe90 fs/read_write.c:1413 C_SYSC_sendfile fs/read_write.c:1489 [inline] compat_SyS_sendfile+0xea/0x1a0 fs/read_write.c:1478 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:125 RIP: 0023:0xf7f86c79 RSP: 002b:00000000f778208c EFLAGS: 00000296 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000000000014 RDX: 000000002099eff8 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 10338: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3711 [inline] __kmalloc_track_caller+0x15e/0x760 mm/slab.c:3726 memdup_user+0x2c/0x90 mm/util.c:164 proc_pid_attr_write+0x115/0x280 fs/proc/base.c:2534 __vfs_write+0xef/0x970 fs/read_write.c:480 __kernel_write+0xfe/0x350 fs/read_write.c:501 write_pipe_buf+0x175/0x220 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x328/0x730 fs/splice.c:626 splice_from_pipe+0x1e9/0x330 fs/splice.c:661 default_file_splice_write+0x40/0x90 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x125/0x180 fs/splice.c:1018 splice_direct_to_actor+0x2c1/0x820 fs/splice.c:973 do_splice_direct+0x2a7/0x3d0 fs/splice.c:1061 do_sendfile+0x5d5/0xe90 fs/read_write.c:1413 C_SYSC_sendfile fs/read_write.c:1489 [inline] compat_SyS_sendfile+0xea/0x1a0 fs/read_write.c:1478 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:125 Freed by task 7878: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3491 [inline] kfree+0xca/0x250 mm/slab.c:3806 kvm_destroy_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:557 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:707 [inline] kvm_put_kvm+0x28e/0xdf0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:747 kvm_vm_release+0x42/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:758 __fput+0x333/0x7f0 fs/file_table.c:210 ____fput+0x15/0x20 fs/file_table.c:244 task_work_run+0x199/0x270 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9bb/0x1ae0 kernel/exit.c:865 do_group_exit+0x149/0x400 kernel/exit.c:968 get_signal+0x73f/0x16c0 kernel/signal.c:2335 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:264 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline] do_fast_syscall_32+0xbfd/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:125 The buggy address belongs to the object at ffff8801c3006600 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 1 bytes inside of 32-byte region [ffff8801c3006600, ffff8801c3006620) The buggy address belongs to the page: page:00000000ff0a725c count:1 mapcount:0 mapping:00000000b6b70cca index:0xffff8801c3006fc1 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c3006000 ffff8801c3006fc1 000000010000003f raw: ffffea00070c4ee0 ffffea00070a00e0 ffff8801db0001c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c3006500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c3006580: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8801c3006600: 01 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8801c3006680: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8801c3006700: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ==================================================================