+ lib-introduce-simple-error-checking-wrapper-for-memparse.patch added to mm-nonmm-unstable branch

+ lib-introduce-simple-error-checking-wrapper-for-memparse.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: lib: introduce simple error-checking wrapper for memparse()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     lib-introduce-simple-error-checking-wrapper-for-memparse.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-introduce-simple-error-checking-wrapper-for-memparse.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Dmitry Antipov <dmantipov@yandex.ru>
Subject: lib: introduce simple error-checking wrapper for memparse()
Date: Thu, 8 Jan 2026 19:52:15 +0300

Introduce 'memvalue()' which uses 'memparse()' to parse a string with
optional memory suffix into a non-negative number.  If parsing has
succeeded, returns 0 and stores the result at the location specified by
the second argument.  Otherwise returns -EINVAL and leaves the location
untouched.

Link: https://lkml.kernel.org/r/20260108165216.1054625-1-dmantipov@yandex.ru
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Kees Cook <kees@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Cc: Andy Shevchenko <andy@kernel.org>
Cc: Carlos Maiolino <cem@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/string.h |    1 +
 lib/cmdline.c          |   26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

--- a/include/linux/string.h~lib-introduce-simple-error-checking-wrapper-for-memparse
+++ a/include/linux/string.h
@@ -319,6 +319,7 @@ DEFINE_FREE(argv_free, char **, if (!IS_
 extern int get_option(char **str, int *pint);
 extern char *get_options(const char *str, int nints, int *ints);
 extern unsigned long long memparse(const char *ptr, char **retptr);
+extern int __must_check memvalue(const char *ptr, unsigned long long *valptr);
 extern bool parse_option_str(const char *str, const char *option);
 extern char *next_arg(char *args, char **param, char **val);
 
--- a/lib/cmdline.c~lib-introduce-simple-error-checking-wrapper-for-memparse
+++ a/lib/cmdline.c
@@ -191,6 +191,32 @@ unsigned long long memparse(const char *
 EXPORT_SYMBOL(memparse);
 
 /**
+ *	memvalue -  Wrap memparse() with simple error detection
+ *	@ptr: Where parse begins
+ *	@valptr: Where to store result
+ *
+ *	Unconditionally returns -EINVAL for a presumably negative value.
+ *	Otherwise uses memparse() to parse a string into a number stored
+ *	at @valptr and returns 0 or -EINVAL if an unrecognized character
+ *	was encountered. For a non-zero return value, memory at @valptr
+ *	is left untouched.
+ */
+int __must_check memvalue(const char *ptr, unsigned long long *valptr)
+{
+	unsigned long long ret;
+	char *end;
+
+	if (*ptr == '-')
+		return -EINVAL;
+	ret = memparse(ptr, &end);
+	if (*end)
+		return -EINVAL;
+	*valptr = ret;
+	return 0;
+}
+EXPORT_SYMBOL(memvalue);
+
+/**
  *	parse_option_str - Parse a string and check an option is set or not
  *	@str: String to be parsed
  *	@option: option name
_

Patches currently in -mm which might be from dmantipov@yandex.ru are

ocfs2-adjust-ocfs2_xa_remove_entry-to-match-ubsan-boundary-checks.patch
ocfs2-annotate-more-flexible-array-members-with-__counted_by_le.patch
lib-introduce-simple-error-checking-wrapper-for-memparse.patch
xfs-adjust-handling-of-a-few-numerical-mount-options.patch