[PATCH] qemu-io: add cvtnum() error handling for zone commands

[Stefan Hajnoczi]

cvtnum() parses positive int64_t values and returns a negative errno on
failure. Print errors and return early when cvtnum() fails.

While we're at it, also reject nr_zones values greater or equal to 2^32
since they cannot be represented.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: Sam Li <faithilikerun@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qemu-io-cmds.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 47 insertions(+), 1 deletion(-)

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index f5d7202a13..e2fab57183 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -1739,12 +1739,26 @@ static int zone_report_f(BlockBackend *blk, int argc, 
char **argv)
 {
     int ret;
     int64_t offset;
+    int64_t val;
     unsigned int nr_zones;
 
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
-    nr_zones = cvtnum(argv[optind]);
+    val = cvtnum(argv[optind]);
+    if (val < 0) {
+        print_cvtnum_err(val, argv[optind]);
+        return val;
+    }
+    if (val > UINT_MAX) {
+        printf("Number of zones must be less than 2^32\n");
+        return -ERANGE;
+    }
+    nr_zones = val;
 
     g_autofree BlockZoneDescriptor *zones = NULL;
     zones = g_new(BlockZoneDescriptor, nr_zones);
@@ -1780,8 +1794,16 @@ static int zone_open_f(BlockBackend *blk, int argc, char 
**argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_OPEN, offset, len);
     if (ret < 0) {
         printf("zone open failed: %s\n", strerror(-ret));
@@ -1805,8 +1827,16 @@ static int zone_close_f(BlockBackend *blk, int argc, 
char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_CLOSE, offset, len);
     if (ret < 0) {
         printf("zone close failed: %s\n", strerror(-ret));
@@ -1830,8 +1860,16 @@ static int zone_finish_f(BlockBackend *blk, int argc, 
char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_FINISH, offset, len);
     if (ret < 0) {
         printf("zone finish failed: %s\n", strerror(-ret));
@@ -1855,8 +1893,16 @@ static int zone_reset_f(BlockBackend *blk, int argc, 
char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_RESET, offset, len);
     if (ret < 0) {
         printf("zone reset failed: %s\n", strerror(-ret));
-- 
2.45.0