From: Emil Velikov <emil.l.velikov@gmail.com>
Date: Wed, 23 Oct 2024 16:19:53 +0000 (+0100)
Subject: libkmod: stop copying symbol names in kmod_elf_get_modversions()
X-Git-Tag: v34~105
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=069d314f8a4c965c762d4db36ea6eb0cea658801;p=thirdparty%2Fkmod.git

libkmod: stop copying symbol names in kmod_elf_get_modversions()

Since the caller already copies the strings as needed, we can just
point to the elf data directly.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Link: https://github.com/kmod-project/kmod/pull/210
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
---

diff --git a/libkmod/libkmod-elf.c b/libkmod/libkmod-elf.c
index 26254e7a..85c1a959 100644
--- a/libkmod/libkmod-elf.c
+++ b/libkmod/libkmod-elf.c
@@ -483,10 +483,9 @@ static inline void elf_get_modversion_lengths(const struct kmod_elf *elf, size_t
 /* array will be allocated with strings in a single malloc, just free *array */
 int kmod_elf_get_modversions(const struct kmod_elf *elf, struct kmod_modversion **array)
 {
-	size_t off, crclen, namlen, slen, verlen;
+	size_t off, crclen, namlen, verlen;
 	uint64_t sec_off, size;
 	struct kmod_modversion *a;
-	char *itr;
 	int i, count, err;
 
 	elf_get_modversion_lengths(elf, &verlen, &crclen, &namlen);
@@ -505,10 +504,12 @@ int kmod_elf_get_modversions(const struct kmod_elf *elf, struct kmod_modversion
 
 	count = size / verlen;
 
-	off = sec_off;
-	slen = 0;
+	*array = a = malloc(sizeof(struct kmod_modversion) * count);
+	if (*array == NULL)
+		return -errno;
 
-	for (i = 0; i < count; i++, off += verlen) {
+	for (i = 0, off = sec_off; i < count; i++, off += verlen) {
+		uint64_t crc = elf_get_uint(elf, off, crclen);
 		const char *symbol = elf_get_mem(elf, off + crclen);
 		size_t nlen = strnlen(symbol, namlen);
 
@@ -517,33 +518,12 @@ int kmod_elf_get_modversions(const struct kmod_elf *elf, struct kmod_modversion
 			return -EINVAL;
 		}
 
-		if (symbol[0] == '.')
-			nlen--;
-
-		slen += nlen + 1;
-	}
-
-	*array = a = malloc(sizeof(struct kmod_modversion) * count + slen);
-	if (*array == NULL)
-		return -errno;
-
-	itr = (char *)(a + count);
-	off = sec_off;
-
-	for (i = 0; i < count; i++, off += verlen) {
-		uint64_t crc = elf_get_uint(elf, off, crclen);
-		const char *symbol = elf_get_mem(elf, off + crclen);
-		size_t symbollen;
-
 		if (symbol[0] == '.')
 			symbol++;
 
 		a[i].crc = crc;
 		a[i].bind = KMOD_SYMBOL_UNDEF;
-		a[i].symbol = itr;
-		symbollen = strlen(symbol) + 1;
-		memcpy(itr, symbol, symbollen);
-		itr += symbollen;
+		a[i].symbol = symbol;
 	}
 
 	return count;