[v3,09/16] module: Group section index calculations together

Commit Message

Matthew Maurer Aug. 6, 2024, 9:20 p.m. UTC

Group all the index detection together to make the parent function
easier to read.

Signed-off-by: Matthew Maurer <[e-mail]>
---
 kernel/module/main.c | 68 +++++++++++++++++++++++++++++++++-----------
 1 file changed, 51 insertions(+), 17 deletions(-)

Patch

diff --git a/kernel/module/main.c b/kernel/module/main.c
index dec733989ad6..a3a4acdcd647 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2039,6 +2039,56 @@  static int elf_validity_cache_index_str(struct load_info *info)
 	return 0;
 }
 
+/**
+ * elf_validity_cache_index() - Resolve, validate, cache section indices
+ * @info:  Load info to read from and update.
+ *         &load_info->sechdrs and &load_info->secstrings must be populated.
+ * @flags: Load flags, relevant to suppress version loading, see
+ *         uapi/linux/module.h
+ *
+ * Populates &load_info->index, validating as it goes.
+ * See child functions for per-field validation:
+ *
+ * * elf_validity_cache_index_info()
+ * * elf_validity_cache_index_mod()
+ * * elf_validity_cache_index_sym()
+ * * elf_validity_cache_index_str()
+ *
+ * If versioning is not suppressed via flags, load the version index from
+ * a section called "__versions" with no validation.
+ *
+ * If CONFIG_SMP is enabled, load the percpu section by name with no
+ * validation.
+ *
+ * Return: 0 on success, negative error code if an index failed validation.
+ */
+static int elf_validity_cache_index(struct load_info *info, int flags)
+{
+	int err;
+
+	err = elf_validity_cache_index_info(info);
+	if (err < 0)
+		return err;
+	err = elf_validity_cache_index_mod(info);
+	if (err < 0)
+		return err;
+	err = elf_validity_cache_index_sym(info);
+	if (err < 0)
+		return err;
+	err = elf_validity_cache_index_str(info);
+	if (err < 0)
+		return err;
+
+	if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
+		info->index.vers = 0; /* Pretend no __versions section! */
+	else
+		info->index.vers = find_sec(info, "__versions");
+
+	info->index.pcpu = find_pcpusec(info);
+
+	return 0;
+}
+
 /*
  * Check userspace passed ELF module against our expectations, and cache
  * useful variables for further processing as we go.
@@ -2069,16 +2119,7 @@  static int elf_validity_cache_copy(struct load_info *info, int flags)
 	err = elf_validity_cache_secstrings(info);
 	if (err < 0)
 		return err;
-	err = elf_validity_cache_index_info(info);
-	if (err < 0)
-		return err;
-	err = elf_validity_cache_index_mod(info);
-	if (err < 0)
-		return err;
-	err = elf_validity_cache_index_sym(info);
-	if (err < 0)
-		return err;
-	err = elf_validity_cache_index_str(info);
+	err = elf_validity_cache_index(info, flags);
 	if (err < 0)
 		return err;
 
@@ -2095,13 +2136,6 @@  static int elf_validity_cache_copy(struct load_info *info, int flags)
 	if (!info->name)
 		info->name = info->mod->name;
 
-	if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
-		info->index.vers = 0; /* Pretend no __versions section! */
-	else
-		info->index.vers = find_sec(info, "__versions");
-
-	info->index.pcpu = find_pcpusec(info);
-
 	return 0;
 }