summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--src/gpt-auto-generator/gpt-auto-generator.c36
1 files changed, 34 insertions, 2 deletions
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 612a3fe777..f05544f3d4 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -664,8 +664,40 @@ static int get_block_device_harder(const char *path, dev_t *dev) {
if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN))
continue;
- if (found) /* Don't try to support multiple backing block devices */
- goto fallback;
+ if (found) {
+ _cleanup_free_ char *u = NULL, *v = NULL, *a = NULL, *b = NULL;
+
+ /* We found a device backed by multiple other devices. We don't really support automatic
+ * discovery on such setups, with the exception of dm-verity partitions. In this case there are
+ * two backing devices: the data partitoin and the hash partition. We are fine with such
+ * setups, however, only if both partitions are on the same physical device. Hence, let's
+ * verify this. */
+
+ u = strjoin(p, "/", de->d_name, "/../dev");
+ if (!u)
+ return -ENOMEM;
+
+ v = strjoin(p, "/", found->d_name, "/../dev");
+ if (!v)
+ return -ENOMEM;
+
+ r = read_one_line_file(u, &a);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to read %s: %m", u);
+ goto fallback;
+ }
+
+ r = read_one_line_file(v, &b);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to read %s: %m", v);
+ goto fallback;
+ }
+
+ /* Check if the parent device is the same. If not, then the two backing devices are on
+ * different physical devices, and we don't support that. */
+ if (!streq(a, b))
+ goto fallback;
+ }
found = de;
}