From: Pali Rohár <pali.rohar@gmail.com>
Date: Sun, 8 Nov 2020 00:51:28 +0000 (+0100)
Subject: libblkid: fix blkid_probe_get_sb() to use hint offset calculation
X-Git-Tag: v2.37-rc1~266^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b5c5b42014619358371addfd7864dc9401647745;p=thirdparty%2Futil-linux.git

libblkid: fix blkid_probe_get_sb() to use hint offset calculation
---

diff --git a/libblkid/src/blkidP.h b/libblkid/src/blkidP.h
index df335f1b1b..a3fe6748a9 100644
--- a/libblkid/src/blkidP.h
+++ b/libblkid/src/blkidP.h
@@ -428,9 +428,9 @@ extern int blkid_probe_get_idmag(blkid_probe pr, const struct blkid_idinfo *id,
 			__attribute__((nonnull(1)));
 
 /* returns superblock according to 'struct blkid_idmag' */
+extern unsigned char *_blkid_probe_get_sb(blkid_probe pr, const struct blkid_idmag *mag, size_t size);
 #define blkid_probe_get_sb(_pr, _mag, type) \
-			((type *) blkid_probe_get_buffer((_pr),\
-					(_mag)->kboff << 10, sizeof(type)))
+			((type *) _blkid_probe_get_sb((_pr), _mag, sizeof(type)))
 
 extern blkid_partlist blkid_probe_get_partlist(blkid_probe pr)
 			__attribute__((nonnull))
diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index 7c29b7fdcf..35977edef4 100644
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -1035,6 +1035,16 @@ int blkid_probe_set_dimension(blkid_probe pr, uint64_t off, uint64_t size)
 	return 0;
 }
 
+unsigned char *_blkid_probe_get_sb(blkid_probe pr, const struct blkid_idmag *mag, size_t size)
+{
+	uint64_t hint_offset;
+
+	if (!mag->hoff || blkid_probe_get_hint(pr, mag->hoff, &hint_offset) < 0)
+		hint_offset = 0;
+
+	return blkid_probe_get_buffer(pr, hint_offset + (mag->kboff << 10), size);
+}
+
 /*
  * Check for matching magic value.
  * Returns BLKID_PROBE_OK if found, BLKID_PROBE_NONE if not found