audit: type=1400 audit(1642173464.202:51): avc: denied { watch } for pid=13812 comm="syz-executor.6" path="/proc/13812/ns" dev="proc" ino=35891 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dir permissive=1 ================================================================== BUG: KASAN: use-after-free in get_kprobe+0xa1/0xc0 kernel/kprobes.c:372 Read of size 8 at addr ffff8880491c0328 by task syz-executor.2/13829 CPU: 0 PID: 13829 Comm: syz-executor.2 Not tainted 5.10.90 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:118 print_address_description.constprop.0+0x1c/0x210 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report.cold+0x37/0x7c mm/kasan/report.c:562 get_kprobe+0xa1/0xc0 kernel/kprobes.c:372 __recover_optprobed_insn+0x31/0x220 arch/x86/kernel/kprobes/opt.c:44 recover_probed_instruction+0x1c/0xf0 arch/x86/kernel/kprobes/core.c:275 can_probe+0xc7/0x1b0 arch/x86/kernel/kprobes/core.c:303 arch_prepare_kprobe+0x79/0x1b0 arch/x86/kernel/kprobes/core.c:499 prepare_kprobe kernel/kprobes.c:1117 [inline] register_kprobe kernel/kprobes.c:1720 [inline] register_kprobe+0x9af/0x1330 kernel/kprobes.c:1682 __register_trace_kprobe kernel/trace/trace_kprobe.c:514 [inline] __register_trace_kprobe+0x262/0x2d0 kernel/trace/trace_kprobe.c:482 create_local_trace_kprobe+0x1e6/0x3b0 kernel/trace/trace_kprobe.c:1837 perf_kprobe_init+0x18c/0x280 kernel/trace/trace_event_perf.c:272 perf_kprobe_event_init+0xf8/0x1c0 kernel/events/core.c:9602 perf_try_init_event+0x130/0x570 kernel/events/core.c:10980 perf_init_event kernel/events/core.c:11032 [inline] perf_event_alloc.part.0+0xd96/0x2b30 kernel/events/core.c:11310 perf_event_alloc kernel/events/core.c:11689 [inline] __do_sys_perf_event_open+0x57c/0x2d00 kernel/events/core.c:11787 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7ffb1e0efb19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffb1b644188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007ffb1e203020 RCX: 00007ffb1e0efb19 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020001d80 RBP: 00007ffb1e149f6d R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcbb79a61f R14: 00007ffb1b644300 R15: 0000000000022000 Allocated by task 13817: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] alloc_aggr_kprobe+0x41/0x190 kernel/kprobes.c:822 try_to_optimize_kprobe kernel/kprobes.c:853 [inline] register_kprobe kernel/kprobes.c:1740 [inline] register_kprobe+0xb78/0x1330 kernel/kprobes.c:1682 __register_trace_kprobe kernel/trace/trace_kprobe.c:514 [inline] __register_trace_kprobe+0x262/0x2d0 kernel/trace/trace_kprobe.c:482 create_local_trace_kprobe+0x1e6/0x3b0 kernel/trace/trace_kprobe.c:1837 perf_kprobe_init+0x18c/0x280 kernel/trace/trace_event_perf.c:272 perf_kprobe_event_init+0xf8/0x1c0 kernel/events/core.c:9602 perf_try_init_event+0x130/0x570 kernel/events/core.c:10980 perf_init_event kernel/events/core.c:11032 [inline] perf_event_alloc.part.0+0xd96/0x2b30 kernel/events/core.c:11310 perf_event_alloc kernel/events/core.c:11689 [inline] __do_sys_perf_event_open+0x57c/0x2d00 kernel/events/core.c:11787 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 5427: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0x110/0x150 mm/kasan/common.c:422 slab_free_hook mm/slub.c:1542 [inline] slab_free_freelist_hook+0xa9/0x180 mm/slub.c:1576 slab_free mm/slub.c:3149 [inline] kfree+0xd7/0x380 mm/slub.c:4125 free_aggr_kprobe kernel/kprobes.c:434 [inline] do_free_cleaned_kprobes kernel/kprobes.c:586 [inline] kprobe_optimizer+0x56f/0x7e0 kernel/kprobes.c:624 process_one_work+0x9a9/0x1590 kernel/workqueue.c:2270 worker_thread+0x61d/0x1310 kernel/workqueue.c:2416 kthread+0x38f/0x470 kernel/kthread.c:313 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:296 The buggy address belongs to the object at ffff8880491c0300 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 40 bytes inside of 192-byte region [ffff8880491c0300, ffff8880491c03c0) The buggy address belongs to the page: page:000000004767f95c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x491c0 flags: 0x100000000000200(slab) raw: 0100000000000200 0000000000000000 0000000100000001 ffff888007c41500 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880491c0200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880491c0280: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880491c0300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880491c0380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880491c0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================