qemu-io: reject invalid pattern
Replace the use of atoi which is used for pattern parsing currently with
strtol. Atoi won't parse sedecimal pattern values (it always returns 0),
but qemu-iotests use such pattern values. Also reject every pattern
that is not a unsigned char as we pass the pattern to memset which
expect a bye value (despite having the pattern argument declared as int).
Based on an earlier patch by Stefan Weil which did not include the
error handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/qemu-io.c b/qemu-io.c
index f938575..029ee0b 100644
--- a/qemu-io.c
+++ b/qemu-io.c
@@ -26,6 +26,26 @@
static int misalign;
/*
+ * Parse the pattern argument to various sub-commands.
+ *
+ * Because the pattern is used as an argument to memset it must evaluate
+ * to an unsigned integer that fits into a single byte.
+ */
+static int parse_pattern(const char *arg)
+{
+ char *endptr = NULL;
+ long pattern;
+
+ pattern = strtol(arg, &endptr, 0);
+ if (pattern < 0 || pattern > UCHAR_MAX || *endptr != '\0') {
+ printf("%s is not a valid pattern byte\n", arg);
+ return -1;
+ }
+
+ return pattern;
+}
+
+/*
* Memory allocation helpers.
*
* Make sure memory is aligned by default, or purposefully misaligned if
@@ -304,7 +324,9 @@
break;
case 'P':
Pflag = 1;
- pattern = atoi(optarg);
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
break;
case 'q':
qflag = 1;
@@ -469,7 +491,9 @@
break;
case 'P':
Pflag = 1;
- pattern = atoi(optarg);
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
break;
case 'q':
qflag = 1;
@@ -594,7 +618,9 @@
pflag = 1;
break;
case 'P':
- pattern = atoi(optarg);
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
break;
case 'q':
qflag = 1;
@@ -721,7 +747,9 @@
qflag = 1;
break;
case 'P':
- pattern = atoi(optarg);
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
break;
default:
return command_usage(&writev_cmd);
@@ -895,7 +923,9 @@
break;
case 'P':
ctx->Pflag = 1;
- ctx->pattern = atoi(optarg);
+ ctx->pattern = parse_pattern(optarg);
+ if (ctx->pattern < 0)
+ return 0;
break;
case 'q':
ctx->qflag = 1;
@@ -995,7 +1025,9 @@
ctx->qflag = 1;
break;
case 'P':
- pattern = atoi(optarg);
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
break;
default:
free(ctx);
