From: Jamie Magee <jamie.magee@gmail.com>
Date: Mon, 4 May 2026 15:47:59 +0000 (-0700)
Subject: libfdisk: gpt: use ul_strtou16 for attribute bit parsing
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8dce82b3b7ab5e29133bd0bb41ba2f5d04235648;p=thirdparty%2Futil-linux.git

libfdisk: gpt: use ul_strtou16 for attribute bit parsing

Replace bare strtol() with ul_strtou16() which folds the errno/end-pointer/empty-input checks into one call and uses a uint16_t result type matching the bit-index domain. Also add udevadm settle between write/read sfdisk calls in the new attribute subtests.
---

diff --git a/libfdisk/src/gpt.c b/libfdisk/src/gpt.c
index 1c98d859e..2511361f6 100644
--- a/libfdisk/src/gpt.c
+++ b/libfdisk/src/gpt.c
@@ -1851,24 +1851,40 @@ static int gpt_entry_attrs_from_string(
 		} else if (isdigit((unsigned char) *p)
 			   || (strncmp(p, "GUID:", 5) == 0
 			       && isdigit((unsigned char) *(p + 5)))) {
-			char *end = NULL;
+			const char *num_start, *num_end;
+			char buf[32];
+			size_t len;
+			uint16_t val;
 			int is_guid = (*p == 'G');
 
 			if (is_guid)
 				p += 5;
 
-			errno = 0;
-			bit = strtol(p, &end, 0);
-			if (errno || !end || end == p)
-				bit = -1;
-			else if (bit >= GPT_ATTRBIT_GUID_FIRST
-				 && bit < GPT_ATTRBIT_GUID_FIRST + GPT_ATTRBIT_GUID_COUNT)
-				p = end;
-			else if (!is_guid && bit >= GPT_ATTRBIT_REQ
-				 && bit <= GPT_ATTRBIT_LEGACY)
-				p = end;
-			else
+			num_start = p;
+			num_end = p;
+			while (*num_end && *num_end != ',' && !isblank(*num_end))
+				num_end++;
+			len = num_end - num_start;
+
+			if (len == 0 || len >= sizeof(buf)) {
 				bit = -1;
+			} else {
+				memcpy(buf, num_start, len);
+				buf[len] = '\0';
+
+				if (ul_strtou16(buf, &val, 0) != 0)
+					bit = -1;
+				else if (val >= GPT_ATTRBIT_GUID_FIRST
+					 && val < GPT_ATTRBIT_GUID_FIRST + GPT_ATTRBIT_GUID_COUNT) {
+					bit = val;
+					p = num_end;
+				} else if (!is_guid && val >= GPT_ATTRBIT_REQ
+					   && val <= GPT_ATTRBIT_LEGACY) {
+					bit = val;
+					p = num_end;
+				} else
+					bit = -1;
+			}
 		}
 
 		if (bit < 0) {
diff --git a/tests/ts/sfdisk/gpt b/tests/ts/sfdisk/gpt
index 10290485b..80659c2ef 100755
--- a/tests/ts/sfdisk/gpt
+++ b/tests/ts/sfdisk/gpt
@@ -132,6 +132,7 @@ ts_finalize_subtest
 
 ts_init_subtest "attrs-numeric-named"
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 "0,1,2" >> $TS_OUTPUT 2>> $TS_ERRLOG
+udevadm settle
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 >> $TS_OUTPUT 2>> $TS_ERRLOG
 ts_fdisk_clean $TS_DEVICE
 udevadm settle
@@ -140,6 +141,7 @@ ts_finalize_subtest
 
 ts_init_subtest "attrs-numeric-mixed"
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 "2,GUID:60" >> $TS_OUTPUT 2>> $TS_ERRLOG
+udevadm settle
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 >> $TS_OUTPUT 2>> $TS_ERRLOG
 ts_fdisk_clean $TS_DEVICE
 udevadm settle
@@ -148,6 +150,7 @@ ts_finalize_subtest
 
 ts_init_subtest "attrs-numeric-hex"
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 "0x2" >> $TS_OUTPUT 2>> $TS_ERRLOG
+udevadm settle
 $TS_CMD_SFDISK --part-attrs ${TS_DEVICE} 2 >> $TS_OUTPUT 2>> $TS_ERRLOG
 ts_fdisk_clean $TS_DEVICE
 udevadm settle