svn commit: r364752 - user/pho/stress2/misc

[Peter Holm]

Author: pho
Date: Tue Aug 25 05:15:40 2020
New Revision: 364752
URL: https://svnweb.freebsd.org/changeset/base/364752

Log:
  Added a syzkaller reproducer.

Added:
  user/pho/stress2/misc/syzkaller22.sh   (contents, props changed)

Added: user/pho/stress2/misc/syzkaller22.sh
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ user/pho/stress2/misc/syzkaller22.sh	Tue Aug 25 05:15:40 2020	(r364752)
@@ -0,0 +1,71 @@
+#!/bin/sh
+
+# panic: Assertion *buflen >= 2 failed at ../../../kern/vfs_cache.c:2837
+# cpuid = 21
+# time = 1598296274
+# KDB: stack backtrace:
+# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0149a9e860
+# vpanic() at vpanic+0x182/frame 0xfffffe0149a9e8b0
+# panic() at panic+0x43/frame 0xfffffe0149a9e910
+# vn_fullpath_any_smr() at vn_fullpath_any_smr+0x4df/frame 0xfffffe0149a9e980
+# sys___realpathat() at sys___realpathat+0x20b/frame 0xfffffe0149a9ead0
+# amd64_syscall() at amd64_syscall+0x159/frame 0xfffffe0149a9ebf0
+# fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0149a9ebf0
+# --- syscall (0, FreeBSD ELF64, nosys), rip = 0x8004294ea, rsp = 0x7fffffffe548, rbp = 0x7fffffffe580 ---
+# KDB: enter: panic
+# [ thread pid 2831 tid 100306 ]
+# Stopped at      kdb_enter+0x37: movq    $0,0x10b4246(%rip)
+# db> x/s version
+# version:        FreeBSD 13.0-CURRENT #0 r364722: Mon Aug 24 21:04:09 CEST 2020
+# pho at t2.osted.lan:/usr/src/sys/amd64/compile/PHO\012
+# db>
+
+# $FreeBSD$
+
+[ `uname -p` != "amd64" ] && exit 0
+
+# Obtained from markj (syzkaller).
+# Fixed by r364723.
+
+. ../default.cfg
+kldstat -v | grep -q sctp || kldload sctp.ko
+cat > /tmp/syzkaller22.c <<EOF
+// autogenerated by syzkaller (https://github.com/google/syzkaller)
+
+#define _GNU_SOURCE
+
+#include <pwd.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/endian.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+uint64_t r[1] = {0xffffffffffffffff};
+
+int main(void)
+{
+	syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul);
+	intptr_t res = 0;
+	memcpy((void*)0x20000000, "./file0\000", 8);
+	syscall(SYS_open, 0x20000000ul, 0x200645ul, 0ul);
+	memcpy((void*)0x20000000, ".\000", 2);
+	res = syscall(SYS_open, 0x20000000ul, 0ul, 0ul);
+	if (res != -1)
+		r[0] = res;
+	memcpy((void*)0x20000240, "./file0\000", 8);
+	syscall(SYS___realpathat, r[0], 0x20000240ul, 0x20000280ul, 8ul, 0ul);
+	return 0;
+}
+EOF
+mycc -o /tmp/syzkaller22 -Wall -Wextra -O0 /tmp/syzkaller22.c ||
+    exit 1
+
+(cd /tmp; timeout 1m ./syzkaller22)
+
+rm -f /tmp/syzkaller22 /tmp/syzkaller22.c /tmp/syzkaller22.core /tmp/file0
+exit 0