Revert "UBUNTU: SAUCE: modpost: support arbitrary symbol length in mo…

…dversion"

This reverts commit 47d27f2.

We need to revert this to avoid regressing any modules used in Jammy.

Signed-off-by: Ian May <[email protected]>

arch/powerpc/kernel/module_64.c

@@ -347,13 +347,12 @@ static unsigned long get_got_size(const Elf64_Ehdr *hdr,
 static void dedotify_versions(struct modversion_info *vers,
 			      unsigned long size)
 {
-	struct modversion_info *end = (void *)vers + size;
+	struct modversion_info *end;
 
-	for (; vers < end && vers->next; vers = (void *)vers + vers->next) {
+	for (end = (void *)vers + size; vers < end; vers++)
 		if (vers->name[0] == '.') {
 			memmove(vers->name, vers->name+1, strlen(vers->name));
 		}
-	}
 }
 
 /*

include/linux/module.h

@@ -35,11 +35,9 @@
 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
 
 struct modversion_info {
-	/* Offset of the next modversion entry in relation to this one. */
-	u32 next;
-	u32 crc;
-	char name[]; /* Flexible array member */
-} __packed;
+	unsigned long crc;
+	char name[MODULE_NAME_LEN];
+};
 
 struct module;
 struct exception_table_entry;

kernel/module/version.c

@@ -17,30 +17,32 @@ int check_version(const struct load_info *info,
 {
 	Elf_Shdr *sechdrs = info->sechdrs;
 	unsigned int versindex = info->index.vers;
-	struct modversion_info *versions, *end;
-	u32 crcval;
+	unsigned int i, num_versions;
+	struct modversion_info *versions;
 
 	/* Exporting module didn't supply crcs?  OK, we're already tainted. */
 	if (!crc)
 		return 1;
-	crcval = *crc;
 
 	/* No versions at all?  modprobe --force does this. */
 	if (versindex == 0)
 		return try_to_force_load(mod, symname) == 0;
 
 	versions = (void *)sechdrs[versindex].sh_addr;
-	end = (void *)versions + sechdrs[versindex].sh_size;
+	num_versions = sechdrs[versindex].sh_size
+		/ sizeof(struct modversion_info);
 
-	for (; versions < end && versions->next;
-	       versions = (void *)versions + versions->next) {
-		if (strcmp(versions->name, symname) != 0)
+	for (i = 0; i < num_versions; i++) {
+		u32 crcval;
+
+		if (strcmp(versions[i].name, symname) != 0)
 			continue;
 
-		if (versions->crc == crcval)
+		crcval = *crc;
+		if (versions[i].crc == crcval)
 			return 1;
-		pr_debug("Found checksum %X vs module %X\n",
-			 crcval, versions->crc);
+		pr_debug("Found checksum %X vs module %lX\n",
+			 crcval, versions[i].crc);
 		goto bad_version;
 	}
 

scripts/export_report.pl

@@ -116,19 +116,18 @@ sub collectcfiles {
 	while ( <$module> ) {
 		chomp;
 		if ($state == 0) {
-			$state = 1 if ($_ =~ /static const char ____versions/);
+			$state = 1 if ($_ =~ /static const struct modversion_info/);
 			next;
 		}
 		if ($state == 1) {
-			$state = 2 if ($_ =~ /__used __section\("__versions"\)/);
+			$state = 2 if ($_ =~ /__attribute__\(\(section\("__versions"\)\)\)/);
 			next;
 		}
 		if ($state == 2) {
-			if ( $_ !~ /\\0"/ ) {
-				last if ($_ =~ /;/);
+			if ( $_ !~ /0x[0-9a-f]+,/ ) {
 				next;
 			}
-			my $sym = (split /(["\\])/,)[2];
+			my $sym = (split /([,"])/,)[4];
 			my ($module, $value, $symbol, $gpl) = @{$SYMBOL{$sym}};
 			$SYMBOL{ $sym } =  [ $module, $value+1, $symbol, $gpl];
 			push(@{$MODULE{$thismod}} , $sym);

scripts/mod/modpost.c

@@ -1906,17 +1906,13 @@ static void add_exported_symbols(struct buffer *buf, struct module *mod)
 static void add_versions(struct buffer *b, struct module *mod)
 {
 	struct symbol *s;
-	unsigned int name_len;
-	unsigned int name_len_padded;
-	unsigned int tmp;
-	unsigned char *tmp_view = (unsigned char *)&tmp;
 
 	if (!modversions)
 		return;
 
 	buf_printf(b, "\n");
-	buf_printf(b, "static const char ____versions[]\n");
-	buf_printf(b, "__used __section(\"__versions\") =\n");
+	buf_printf(b, "static const struct modversion_info ____versions[]\n");
+	buf_printf(b, "__used __section(\"__versions\") = {\n");
 
 	list_for_each_entry(s, &mod->unresolved_symbols, list) {
 		if (!s->module)
@@ -1926,27 +1922,16 @@ static void add_versions(struct buffer *b, struct module *mod)
 				s->name, mod->name);
 			continue;
 		}
-		name_len = strlen(s->name);
-		name_len_padded = (name_len + 1 + 3) & ~3;
-
-		/* Offset to next entry */
-		tmp = 8 + name_len_padded;
-		tmp = TO_NATIVE(tmp);
-		buf_printf(b, "\t\"\\x%02x\\x%02x\\x%02x\\x%02x",
-			   tmp_view[0], tmp_view[1], tmp_view[2], tmp_view[3]);
-
-		tmp = TO_NATIVE(s->crc);
-		buf_printf(b, "\\x%02x\\x%02x\\x%02x\\x%02x\"\n",
-			   tmp_view[0], tmp_view[1], tmp_view[2], tmp_view[3]);
-
-		buf_printf(b, "\t\"%s", s->name);
-		for (; name_len < name_len_padded; name_len++)
-			buf_printf(b, "\\0");
-		buf_printf(b, "\"\n");
+		if (strlen(s->name) >= MODULE_NAME_LEN) {
+			error("too long symbol \"%s\" [%s.ko]\n",
+			      s->name, mod->name);
+			break;
+		}
+		buf_printf(b, "\t{ %#8x, \"%s\" },\n",
+			   s->crc, s->name);
 	}
 
-	/* Always end with a NULL entry */
-	buf_printf(b, "\t\"\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\";\n");
+	buf_printf(b, "};\n");
 }
 
 static void add_depends(struct buffer *b, struct module *mod)