discover/devmapper: Use explicit 64-bit types for sector counts

We currently have a bug where the return value from get_block_sectors
may overflow an unsigned int, so we create a snapshot that is too small.

This change uses uint64_t types for the sector counts.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/device-handler.h b/discover/device-handler.h
index 58777339d61bb33df2eae5afd7915a093dcab15c..d18910a1315d6f7ebf4da9e0b248e83c13fbad80 100644 (file)
--- a/discover/device-handler.h
+++ b/discover/device-handler.h
@@ -65,7 +65,7 @@ struct ramdisk_device {
        char            *snapshot;
        char            *origin;
        char            *base;
-       unsigned int    sectors;
+       uint64_t        sectors;
 };
 
 struct device_handler *device_handler_init(struct discover_server *server,

diff --git a/discover/devmapper.c b/discover/devmapper.c
index e2ef0b59c279c294355ec28ff6045f150981495e..d3179f14e7fcc52c9eb71e487ac80250e44fbf05 100644 (file)
--- a/discover/devmapper.c
+++ b/discover/devmapper.c
@@ -11,17 +11,17 @@
 #define MERGE_INTERVAL_US      200000
 
 struct target {
-       long unsigned int       start_sector;
-       long unsigned int       end_sector;
-       char                    *ttype;
-       char                    *params;
+       uint64_t        start_sector;
+       uint64_t        end_sector;
+       char            *ttype;
+       char            *params;
 };
 
 /* Return the number of sectors on a block device. Zero represents an error */
-static unsigned int get_block_sectors(struct discover_device *device)
+static uint64_t get_block_sectors(struct discover_device *device)
 {
+       unsigned long long sectors;
        const char *tmp;
-       long unsigned int sectors;
 
        tmp = discover_device_get_param(device, "ID_PART_ENTRY_SIZE");
        if (!tmp) {
@@ -31,14 +31,14 @@ static unsigned int get_block_sectors(struct discover_device *device)
        }
 
        errno = 0;
-       sectors = strtoul(tmp, NULL, 0);
+       sectors = strtoull(tmp, NULL, 0);
        if (errno) {
                pb_debug("Error reading sector count for %s: %s\n",
                       device->device_path, strerror(errno));
                sectors = 0;
        }
 
-       return sectors;
+       return (uint64_t)sectors;
 }
 
 /*
@@ -60,7 +60,7 @@ static inline int set_cookie(struct dm_task *task, uint32_t *cookie)
 
 static bool snapshot_merge_complete(const char *dm_name)
 {
-       long long unsigned int sectors, meta_sectors;
+       uint64_t sectors, meta_sectors;
        char *params = NULL,  *target_type = NULL;
        uint64_t start, length;
        struct dm_task *task;
@@ -97,14 +97,16 @@ static bool snapshot_merge_complete(const char *dm_name)
 
        /* Merge is complete when metadata sectors are the only sectors
         * allocated - see Documentation/device-mapper/snapshot.txt */
-       n = sscanf(params, "%llu/%*u %llu", &sectors, &meta_sectors);
+       n = sscanf(params, "%" SCNu64 "/%*u %" SCNu64,
+                       &sectors, &meta_sectors);
        if (n != 2) {
                pb_log("%s unexpected status: '%s'\n", dm_name, params);
                goto out;
        }
        result = sectors == meta_sectors;
 
-       pb_debug("%s merging; %llu sectors, %llu metadata sectors\n",
+       pb_debug("%s merging; %" PRIu64 " sectors, %" PRIu64
+                       " metadata sectors\n",
                 dm_name, sectors, meta_sectors);
 
 out: