From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 24 Jun 2024 15:50:34 +0000 (+0200)
Subject: pe: use more correct section name comparison function
X-Git-Tag: v257-rc1~1041^2~28
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9e63e28aa652df483f431ab35a5934d77aab95db;p=thirdparty%2Fsystemd.git

pe: use more correct section name comparison function

we should only compare up to 8 chars
---

diff --git a/src/boot/efi/pe.c b/src/boot/efi/pe.c
index 34b01561f07..cb75c2b42b8 100644
--- a/src/boot/efi/pe.c
+++ b/src/boot/efi/pe.c
@@ -155,6 +155,26 @@ static size_t section_table_offset(const DosFileHeader *dos, const PeFileHeader
         return dos->ExeHeader + offsetof(PeFileHeader, OptionalHeader) + pe->FileHeader.SizeOfOptionalHeader;
 }
 
+static bool pe_section_name_equal(const char *a, const char *b) {
+
+        if (a == b)
+                return true;
+        if (!a != !b)
+                return false;
+
+        /* Compares up to 8 characters of a and b i.e. the name size limit in the PE section header */
+
+        for (size_t i = 0; i < sizeof_field(PeSectionHeader, Name); i++) {
+                if (a[i] != b[i])
+                        return false;
+
+                if (a[i] == 0) /* Name is shorter than 8 */
+                        return true;
+        }
+
+        return true;
+}
+
 static void locate_sections(
                 const PeSectionHeader section_table[],
                 size_t n_table,
@@ -172,7 +192,7 @@ static void locate_sections(
                 const PeSectionHeader *sect = section_table + i;
 
                 for (size_t j = 0; sections[j]; j++) {
-                        if (memcmp(sect->Name, sections[j], strlen8(sections[j])) != 0)
+                        if (!pe_section_name_equal((const char*) sect->Name, sections[j]))
                                 continue;
 
                         offsets[j] = in_memory ? sect->VirtualAddress : sect->PointerToRawData;