qemu-io: better input validation for vector-based commands
Fix up a couple of issues with validating the input of the various
length arguments for the vectored I/O commands:
- do the alignment check on each length instead the always 0 count argument
- use a long long varibale for the cvtnum return value so that we can check
wether it wasn't a number
- check for a too large argument instead of truncating it
Also refactor it into a common helper for all four calers and avoid parsing
the numbers twice.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/qemu-io.c b/qemu-io.c
index 28159d80..e6759db 100644
--- a/qemu-io.c
+++ b/qemu-io.c
@@ -98,6 +98,57 @@
}
}
+/*
+ * Parse multiple length statements for vectored I/O, and construct an I/O
+ * vector matching it.
+ */
+static void *
+create_iovec(QEMUIOVector *qiov, char **argv, int nr_iov, int pattern)
+{
+ size_t *sizes = calloc(nr_iov, sizeof(size_t));
+ size_t count = 0;
+ void *buf, *p;
+ int i;
+
+ for (i = 0; i < nr_iov; i++) {
+ char *arg = argv[i];
+ long long len;
+
+ len = cvtnum(arg);
+ if (len < 0) {
+ printf("non-numeric length argument -- %s\n", arg);
+ return NULL;
+ }
+
+ /* should be SIZE_T_MAX, but that doesn't exist */
+ if (len > UINT_MAX) {
+ printf("too large length argument -- %s\n", arg);
+ return NULL;
+ }
+
+ if (len & 0x1ff) {
+ printf("length argument %lld is not sector aligned\n",
+ len);
+ return NULL;
+ }
+
+ sizes[i] = len;
+ count += len;
+ }
+
+ qemu_iovec_init(qiov, nr_iov);
+
+ buf = p = qemu_io_alloc(count, pattern);
+
+ for (i = 0; i < nr_iov; i++) {
+ qemu_iovec_add(qiov, p, sizes[i]);
+ p += sizes[i];
+ }
+
+ free(sizes);
+ return buf;
+}
+
static int do_read(char *buf, int64_t offset, int count, int *total)
{
int ret;
@@ -375,10 +426,10 @@
struct timeval t1, t2;
int Cflag = 0, qflag = 0, vflag = 0;
int c, cnt;
- char *buf, *p;
+ char *buf;
int64_t offset;
- int count = 0, total;
- int nr_iov, i;
+ int total;
+ int nr_iov;
QEMUIOVector qiov;
int pattern = 0;
int Pflag = 0;
@@ -420,40 +471,8 @@
return 0;
}
- if (count & 0x1ff) {
- printf("count %d is not sector aligned\n",
- count);
- return 0;
- }
-
- for (i = optind; i < argc; i++) {
- size_t len;
-
- len = cvtnum(argv[i]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n", argv[i]);
- return 0;
- }
- count += len;
- }
-
nr_iov = argc - optind;
- qemu_iovec_init(&qiov, nr_iov);
- buf = p = qemu_io_alloc(count, 0xab);
- for (i = 0; i < nr_iov; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n",
- argv[optind]);
- return 0;
- }
-
- qemu_iovec_add(&qiov, p, len);
- p += len;
- optind++;
- }
+ buf = create_iovec(&qiov, &argv[optind], nr_iov, 0xab);
gettimeofday(&t1, NULL);
cnt = do_aio_readv(&qiov, offset, &total);
@@ -465,12 +484,12 @@
}
if (Pflag) {
- void* cmp_buf = malloc(count);
- memset(cmp_buf, pattern, count);
- if (memcmp(buf, cmp_buf, count)) {
+ void* cmp_buf = malloc(qiov.size);
+ memset(cmp_buf, pattern, qiov.size);
+ if (memcmp(buf, cmp_buf, qiov.size)) {
printf("Pattern verification failed at offset %lld, "
- "%d bytes\n",
- (long long) offset, count);
+ "%zd bytes\n",
+ (long long) offset, qiov.size);
}
free(cmp_buf);
}
@@ -646,10 +665,10 @@
struct timeval t1, t2;
int Cflag = 0, qflag = 0;
int c, cnt;
- char *buf, *p;
+ char *buf;
int64_t offset;
- int count = 0, total;
- int nr_iov, i;
+ int total;
+ int nr_iov;
int pattern = 0xcd;
QEMUIOVector qiov;
@@ -685,41 +704,8 @@
return 0;
}
- if (count & 0x1ff) {
- printf("count %d is not sector aligned\n",
- count);
- return 0;
- }
-
-
- for (i = optind; i < argc; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n", argv[i]);
- return 0;
- }
- count += len;
- }
-
nr_iov = argc - optind;
- qemu_iovec_init(&qiov, nr_iov);
- buf = p = qemu_io_alloc(count, pattern);
- for (i = 0; i < nr_iov; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n",
- argv[optind]);
- return 0;
- }
-
- qemu_iovec_add(&qiov, p, len);
- p += len;
- optind++;
- }
+ buf = create_iovec(&qiov, &argv[optind], nr_iov, pattern);
gettimeofday(&t1, NULL);
cnt = do_aio_writev(&qiov, offset, &total);
@@ -859,9 +845,7 @@
static int
aio_read_f(int argc, char **argv)
{
- char *p;
- int count = 0;
- int nr_iov, i, c;
+ int nr_iov, c;
struct aio_ctx *ctx = calloc(1, sizeof(struct aio_ctx));
BlockDriverAIOCB *acb;
@@ -902,40 +886,8 @@
return 0;
}
- if (count & 0x1ff) {
- printf("count %d is not sector aligned\n",
- count);
- return 0;
- }
-
- for (i = optind; i < argc; i++) {
- size_t len;
-
- len = cvtnum(argv[i]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n", argv[i]);
- return 0;
- }
- count += len;
- }
-
nr_iov = argc - optind;
- qemu_iovec_init(&ctx->qiov, nr_iov);
- ctx->buf = p = qemu_io_alloc(count, 0xab);
- for (i = 0; i < nr_iov; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n",
- argv[optind]);
- return 0;
- }
-
- qemu_iovec_add(&ctx->qiov, p, len);
- p += len;
- optind++;
- }
+ ctx->buf = create_iovec(&ctx->qiov, &argv[optind], nr_iov, 0xab);
gettimeofday(&ctx->t1, NULL);
acb = bdrv_aio_readv(bs, ctx->offset >> 9, &ctx->qiov,
@@ -983,9 +935,7 @@
static int
aio_write_f(int argc, char **argv)
{
- char *p;
- int count = 0;
- int nr_iov, i, c;
+ int nr_iov, c;
int pattern = 0xcd;
struct aio_ctx *ctx = calloc(1, sizeof(struct aio_ctx));
BlockDriverAIOCB *acb;
@@ -1022,40 +972,8 @@
return 0;
}
- if (count & 0x1ff) {
- printf("count %d is not sector aligned\n",
- count);
- return 0;
- }
-
- for (i = optind; i < argc; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n", argv[i]);
- return 0;
- }
- count += len;
- }
-
nr_iov = argc - optind;
- qemu_iovec_init(&ctx->qiov, nr_iov);
- ctx->buf = p = qemu_io_alloc(count, pattern);
- for (i = 0; i < nr_iov; i++) {
- size_t len;
-
- len = cvtnum(argv[optind]);
- if (len < 0) {
- printf("non-numeric length argument -- %s\n",
- argv[optind]);
- return 0;
- }
-
- qemu_iovec_add(&ctx->qiov, p, len);
- p += len;
- optind++;
- }
+ ctx->buf = create_iovec(&ctx->qiov, &argv[optind], nr_iov, pattern);
gettimeofday(&ctx->t1, NULL);
acb = bdrv_aio_writev(bs, ctx->offset >> 9, &ctx->qiov,
