libblkid: (probe) handle probe without chain gracefully

Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>

diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index b4299493fb344e2f6f659f0e671a51bfca793267..fbf504a4699e32489424ec42bcc39b5c889ab1a6 100644 (file)
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -1838,7 +1838,7 @@ int blkid_probe_verify_csum_buf(blkid_probe pr, size_t n, const void *csum,
                /*
                 * Accept bad checksum if BLKID_SUBLKS_BADCSUM flags is set
                 */
-               if (chn->driver->id == BLKID_CHAIN_SUBLKS
+               if (chn && chn->driver->id == BLKID_CHAIN_SUBLKS
                    && (chn->flags & BLKID_SUBLKS_BADCSUM)) {
                        blkid_probe_set_value(pr, "SBBADCSUM", (unsigned char *) "1", 2);
                        goto accept;