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BUG: KASAN: out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc900016d7550 by task syz-executor.5/26338

CPU: 1 PID: 26338 Comm: syz-executor.5 Not tainted 5.8.0-rc3-next-20200703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 csd_lock_record+0xcb/0xe0 kernel/smp.c:118
 flush_smp_call_function_queue+0x285/0x730 kernel/smp.c:391
 __sysvec_call_function_single+0x98/0x490 arch/x86/kernel/smp.c:248
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_call_function_single+0xe0/0x120 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:604
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:kfree+0x1e0/0x2c0 mm/slab.c:3761
Code: 4e 7e 0f 85 55 fe ff ff e8 dc 56 4d ff e9 4b fe ff ff e8 93 ae c6 ff 48 83 3d bb dc 01 08 00 0f 84 d2 00 00 00 48 89 df 57 9d <0f> 1f 44 00 00 5b 5d 41 5c 41 5d c3 65 ff 05 1d dc 4e 7e 48 8b 05
RSP: 0018:ffffc900017a7ae0 EFLAGS: 00000282
RAX: 000000000000038f RBX: 0000000000000282 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff88803e73a000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880aa000900
R13: ffffffff8363fd81 R14: ffff88803e73afbc R15: 0000000000001000
 tomoyo_realpath_from_path+0x191/0x620 security/tomoyo/realpath.c:291
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x212/0x3f0 security/tomoyo/file.c:822
 tomoyo_path_symlink+0x94/0xe0 security/tomoyo/tomoyo.c:200
 security_path_symlink+0xdf/0x150 security/security.c:1109
 do_symlinkat+0x123/0x2c0 fs/namei.c:3984
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c8b7
Code: Bad RIP value.
RSP: 002b:00007fff16279d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045c8b7
RDX: 00007fff16279e03 RSI: 00000000004c26a1 RDI: 00007fff16279df0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013
R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001
R13: 00007fff16279da0 R14: 0000000000000000 R15: 00007fff16279db0


Memory state around the buggy address:
 ffffc900016d7400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900016d7480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc900016d7500: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3
                                                    ^
 ffffc900016d7580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900016d7600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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