* [PATCH v8 0/5] lib and lib/cmdline enhancements
@ 2026-02-12 16:44 Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 1/5] lib: fix _parse_integer_limit() to handle overflow Dmitry Antipov
` (5 more replies)
0 siblings, 6 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
Adjust '_parse_integer_limit()' and 'memparse()' to not ignore
overflows, extend string to 64-bit integer conversion tests, add
KUnit-based test for 'memparse()' and fix kernel-doc glitches
found in lib/cmdline.c.
Dmitry Antipov (5):
lib: fix _parse_integer_limit() to handle overflow
lib: fix memparse() to handle overflow
lib: add more string to 64-bit integer conversion overflow tests
lib/cmdline_kunit: add test case for memparse()
lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
lib/cmdline.c | 30 ++++++++++++++-------
lib/kstrtox.c | 37 +++++++++++++++-----------
lib/test-kstrtox.c | 6 +++++
lib/tests/cmdline_kunit.c | 56 +++++++++++++++++++++++++++++++++++++++
4 files changed, 104 insertions(+), 25 deletions(-)
--
2.53.0
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v8 1/5] lib: fix _parse_integer_limit() to handle overflow
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
@ 2026-02-12 16:44 ` Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 2/5] lib: fix memparse() " Dmitry Antipov
` (4 subsequent siblings)
5 siblings, 0 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
In '_parse_integer_limit()', adjust native integer arithmetic
with near-to-overflow branch where 'check_mul_overflow()' and
'check_add_overflow()' are used to check whether an intermediate
result goes out of range, and denote such a case with ULLONG_MAX,
thus making the function more similar to standard C library's
'strtoull()'. Adjust comment to kernel-doc style as well.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v8: do not use explicit temporary in check_xxx_overflow()
calls and handle overflow flag using separate variable
v7: drop redundant check against ULLONG_MAX and restore
original comment
v6: more compact for-loop and minor style adjustments again
v5: minor brace style adjustment
v4: restore plain integer arithmetic and use check_xxx_overflow()
on near-to-overflow branch only
v3: adjust commit message and comments as suggested by Andy
v2: initial version to join the series
---
lib/kstrtox.c | 37 ++++++++++++++++++++++---------------
1 file changed, 22 insertions(+), 15 deletions(-)
diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index bdde40cd69d7..cd67f494c3bd 100644
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -39,25 +39,30 @@ const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
return s;
}
-/*
- * Convert non-negative integer string representation in explicitly given radix
- * to an integer. A maximum of max_chars characters will be converted.
+/**
+ * _parse_integer_limit - Convert integer string representation to an integer
+ * @s: Integer string representation
+ * @base: Radix
+ * @p: Where to store result
+ * @max_chars: Maximum amount of characters to convert
+ *
+ * Convert non-negative integer string representation in explicitly given
+ * radix to an integer. If overflow occurs, value at @p is set to ULLONG_MAX.
*
- * Return number of characters consumed maybe or-ed with overflow bit.
- * If overflow occurs, result integer (incorrect) is still returned.
+ * This function is the workhorse of other string conversion functions and it
+ * is discouraged to use it explicitly. Consider kstrto*() family instead.
*
- * Don't you dare use this function.
+ * Return: Number of characters consumed, maybe ORed with overflow bit
*/
noinline
unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *p,
size_t max_chars)
{
+ unsigned int rv, overflow = 0;
unsigned long long res;
- unsigned int rv;
res = 0;
- rv = 0;
- while (max_chars--) {
+ for (rv = 0; rv < max_chars; rv++, s++) {
unsigned int c = *s;
unsigned int lc = _tolower(c);
unsigned int val;
@@ -76,15 +81,17 @@ unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned lon
* it in the max base we support (16)
*/
if (unlikely(res & (~0ull << 60))) {
- if (res > div_u64(ULLONG_MAX - val, base))
- rv |= KSTRTOX_OVERFLOW;
+ if (check_mul_overflow(res, base, &res) ||
+ check_add_overflow(res, val, &res)) {
+ res = ULLONG_MAX;
+ overflow = KSTRTOX_OVERFLOW;
+ }
+ } else {
+ res = res * base + val;
}
- res = res * base + val;
- rv++;
- s++;
}
*p = res;
- return rv;
+ return rv | overflow;
}
noinline
--
2.53.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v8 2/5] lib: fix memparse() to handle overflow
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 1/5] lib: fix _parse_integer_limit() to handle overflow Dmitry Antipov
@ 2026-02-12 16:44 ` Dmitry Antipov
2026-02-24 12:32 ` Rodrigo Alencar
2026-02-12 16:44 ` [PATCH v8 3/5] lib: add more string to 64-bit integer conversion overflow tests Dmitry Antipov
` (3 subsequent siblings)
5 siblings, 1 reply; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now
capable to handle overflow, adjust 'memparse()' to handle overflow
(denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also
use 'check_shl_overflow()' to catch an overflow possibly caused
by processing size suffix and denote it with ULLONG_MAX as well.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v8: do not use temporary in check_shl_overflow()
v7: do not double-adjust endptr and drop
redundant check against ULLONG_MAX
v6: handle valid-suffix-only string like "k"
as unrecognized, minor style adjustments
v5: initial version to join the series
---
lib/cmdline.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/lib/cmdline.c b/lib/cmdline.c
index 90ed997d9570..f6e4b113ca9f 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -150,39 +150,46 @@ EXPORT_SYMBOL(get_options);
unsigned long long memparse(const char *ptr, char **retptr)
{
char *endptr; /* local pointer to end of parsed string */
-
unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
+ unsigned int shl = 0;
+ /* Consume valid suffix even in case of overflow. */
switch (*endptr) {
case 'E':
case 'e':
- ret <<= 10;
+ shl += 10;
fallthrough;
case 'P':
case 'p':
- ret <<= 10;
+ shl += 10;
fallthrough;
case 'T':
case 't':
- ret <<= 10;
+ shl += 10;
fallthrough;
case 'G':
case 'g':
- ret <<= 10;
+ shl += 10;
fallthrough;
case 'M':
case 'm':
- ret <<= 10;
+ shl += 10;
fallthrough;
case 'K':
case 'k':
- ret <<= 10;
- endptr++;
+ shl += 10;
fallthrough;
default:
break;
}
+ if (shl && likely(ptr != endptr)) {
+ /* Have valid suffix with preceding number. */
+ if (unlikely(check_shl_overflow(ret, shl, &ret)))
+ ret = ULLONG_MAX;
+ endptr++;
+ }
+
if (retptr)
*retptr = endptr;
--
2.53.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v8 3/5] lib: add more string to 64-bit integer conversion overflow tests
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 1/5] lib: fix _parse_integer_limit() to handle overflow Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 2/5] lib: fix memparse() " Dmitry Antipov
@ 2026-02-12 16:44 ` Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 4/5] lib/cmdline_kunit: add test case for memparse() Dmitry Antipov
` (2 subsequent siblings)
5 siblings, 0 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
Add a few more string to 64-bit integer conversion tests to
check whether 'kstrtoull()', 'kstrtoll()', 'kstrtou64()' and
'kstrtos64()' can handle overflows reported by
'_parse_integer_limit()'.
Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v5 and upwards: bump version to match the series
v4: initial version to join the series
---
lib/test-kstrtox.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/lib/test-kstrtox.c b/lib/test-kstrtox.c
index ee87fef66cb5..811128d0df16 100644
--- a/lib/test-kstrtox.c
+++ b/lib/test-kstrtox.c
@@ -198,6 +198,7 @@ static void __init test_kstrtoull_fail(void)
{"10000000000000000000000000000000000000000000000000000000000000000", 2},
{"2000000000000000000000", 8},
{"18446744073709551616", 10},
+ {"569202370375329612767", 10},
{"10000000000000000", 16},
/* negative */
{"-0", 0},
@@ -275,9 +276,11 @@ static void __init test_kstrtoll_fail(void)
{"9223372036854775809", 10},
{"18446744073709551614", 10},
{"18446744073709551615", 10},
+ {"569202370375329612767", 10},
{"-9223372036854775809", 10},
{"-18446744073709551614", 10},
{"-18446744073709551615", 10},
+ {"-569202370375329612767", 10},
/* sign is first character if any */
{"-+1", 0},
{"-+1", 8},
@@ -334,6 +337,7 @@ static void __init test_kstrtou64_fail(void)
{"-1", 10},
{"18446744073709551616", 10},
{"18446744073709551617", 10},
+ {"569202370375329612767", 10},
};
TEST_FAIL(kstrtou64, u64, "%llu", test_u64_fail);
}
@@ -386,6 +390,8 @@ static void __init test_kstrtos64_fail(void)
{"18446744073709551615", 10},
{"18446744073709551616", 10},
{"18446744073709551617", 10},
+ {"569202370375329612767", 10},
+ {"-569202370375329612767", 10},
};
TEST_FAIL(kstrtos64, s64, "%lld", test_s64_fail);
}
--
2.53.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v8 4/5] lib/cmdline_kunit: add test case for memparse()
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
` (2 preceding siblings ...)
2026-02-12 16:44 ` [PATCH v8 3/5] lib: add more string to 64-bit integer conversion overflow tests Dmitry Antipov
@ 2026-02-12 16:44 ` Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 5/5] lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings Dmitry Antipov
2026-02-18 13:40 ` [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
5 siblings, 0 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
Better late than never, now there is a long-awaited basic
test for 'memparse()' which is provided by cmdline.c.
Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v7 and upwards: bump version to match the series
v6: tests to check whether valid-suffix-only string is handled as unrecognized
v5: even more tests to trigger overflow with size suffix
v4: move actual overflow tests to test-kstrtox.c
v3: adjust style as suggested by Andy
v2: few more test cases to trigger overflows
---
lib/tests/cmdline_kunit.c | 56 +++++++++++++++++++++++++++++++++++++++
1 file changed, 56 insertions(+)
diff --git a/lib/tests/cmdline_kunit.c b/lib/tests/cmdline_kunit.c
index c1602f797637..18b19c85baef 100644
--- a/lib/tests/cmdline_kunit.c
+++ b/lib/tests/cmdline_kunit.c
@@ -6,6 +6,7 @@
#include <kunit/test.h>
#include <linux/kernel.h>
#include <linux/random.h>
+#include <linux/sizes.h>
#include <linux/string.h>
static const char *cmdline_test_strings[] = {
@@ -139,11 +140,66 @@ static void cmdline_test_range(struct kunit *test)
} while (++i < ARRAY_SIZE(cmdline_test_range_strings));
}
+struct cmdline_test_memparse_entry {
+ const char *input;
+ const char *unrecognized;
+ unsigned long long result;
+};
+
+static const struct cmdline_test_memparse_entry testdata[] = {
+ { "0", "", 0ULL },
+ { "1", "", 1ULL },
+ { "a", "a", 0ULL },
+ { "k", "k", 0ULL },
+ { "E", "E", 0ULL },
+ { "0xb", "", 11ULL },
+ { "0xz", "x", 0ULL },
+ { "1234", "", 1234ULL },
+ { "04567", "", 2423ULL },
+ { "0x9876", "", 39030LL },
+ { "05678", "8", 375ULL },
+ { "0xabcdefz", "z", 11259375ULL },
+ { "0cdba", "c", 0ULL },
+ { "4K", "", SZ_4K },
+ { "0x10k@0xaaaabbbb", "@", SZ_16K },
+ { "32M", "", SZ_32M },
+ { "067m:foo", ":", 55 * SZ_1M },
+ { "2G;bar=baz", ";", SZ_2G },
+ { "07gz", "z", 7ULL * SZ_1G },
+ { "3T+data", "+", 3 * SZ_1T },
+ { "04t,ro", ",", SZ_4T },
+ { "012p", "", 11258999068426240ULL },
+ { "7P,sync", ",", 7881299347898368ULL },
+ { "0x2e", "", 46ULL },
+ { "2E and more", " ", 2305843009213693952ULL },
+ { "18446744073709551615", "", ULLONG_MAX },
+ { "0xffffffffffffffff0", "", ULLONG_MAX },
+ { "1111111111111111111T", "", ULLONG_MAX },
+ { "222222222222222222222G", "", ULLONG_MAX },
+ { "3333333333333333333333M", "", ULLONG_MAX },
+};
+
+static void cmdline_test_memparse(struct kunit *test)
+{
+ const struct cmdline_test_memparse_entry *e;
+ unsigned long long ret;
+ char *retptr;
+
+ for (e = testdata; e < testdata + ARRAY_SIZE(testdata); e++) {
+ ret = memparse(e->input, &retptr);
+ KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+ " when parsing '%s'", e->input);
+ KUNIT_EXPECT_EQ_MSG(test, *retptr, *e->unrecognized,
+ " when parsing '%s'", e->input);
+ }
+}
+
static struct kunit_case cmdline_test_cases[] = {
KUNIT_CASE(cmdline_test_noint),
KUNIT_CASE(cmdline_test_lead_int),
KUNIT_CASE(cmdline_test_tail_int),
KUNIT_CASE(cmdline_test_range),
+ KUNIT_CASE(cmdline_test_memparse),
{}
};
--
2.53.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v8 5/5] lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
` (3 preceding siblings ...)
2026-02-12 16:44 ` [PATCH v8 4/5] lib/cmdline_kunit: add test case for memparse() Dmitry Antipov
@ 2026-02-12 16:44 ` Dmitry Antipov
2026-02-18 13:40 ` [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
5 siblings, 0 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-12 16:44 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel, Dmitry Antipov
Fix 'get_option()', 'memparse()' and 'parse_option_str()' comments
to match the commonly used style as suggested by kernel-doc -Wreturn.
Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v2 and upwards: bump version to match the series
---
lib/cmdline.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/lib/cmdline.c b/lib/cmdline.c
index f6e4b113ca9f..16cce6621cec 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -43,7 +43,7 @@ static int get_range(char **str, int *pint, int n)
* When @pint is NULL the function can be used as a validator of
* the current option in the string.
*
- * Return values:
+ * Return:
* 0 - no int in string
* 1 - int found, no subsequent comma
* 2 - int found including a subsequent comma
@@ -145,6 +145,9 @@ EXPORT_SYMBOL(get_options);
*
* Parses a string into a number. The number stored at @ptr is
* potentially suffixed with K, M, G, T, P, E.
+ *
+ * Return: The value as recognized by simple_strtoull() multiplied
+ * by the value as specified by suffix, if any.
*/
unsigned long long memparse(const char *ptr, char **retptr)
@@ -205,7 +208,7 @@ EXPORT_SYMBOL(memparse);
* This function parses a string containing a comma-separated list of
* strings like a=b,c.
*
- * Return true if there's such option in the string, or return false.
+ * Return: True if there's such option in the string or false otherwise.
*/
bool parse_option_str(const char *str, const char *option)
{
--
2.53.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
` (4 preceding siblings ...)
2026-02-12 16:44 ` [PATCH v8 5/5] lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings Dmitry Antipov
@ 2026-02-18 13:40 ` Dmitry Antipov
2026-02-18 13:48 ` Andy Shevchenko
5 siblings, 1 reply; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-18 13:40 UTC (permalink / raw)
To: Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel
On Thu, 2026-02-12 at 19:44 +0300, Dmitry Antipov wrote:
> Adjust '_parse_integer_limit()' and 'memparse()' to not ignore
> overflows, extend string to 64-bit integer conversion tests, add
> KUnit-based test for 'memparse()' and fix kernel-doc glitches
> found in lib/cmdline.c.
>
> Dmitry Antipov (5):
> lib: fix _parse_integer_limit() to handle overflow
> lib: fix memparse() to handle overflow
> lib: add more string to 64-bit integer conversion overflow tests
> lib/cmdline_kunit: add test case for memparse()
> lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
Any chance to move forward with this?
Dmitry
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-02-18 13:40 ` [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
@ 2026-02-18 13:48 ` Andy Shevchenko
2026-04-02 6:56 ` Dmitry Antipov
0 siblings, 1 reply; 15+ messages in thread
From: Andy Shevchenko @ 2026-02-18 13:48 UTC (permalink / raw)
To: Dmitry Antipov
Cc: Andrew Morton, David Laight, Kees Cook, Darrick J . Wong,
linux-hardening, linux-kernel
On Wed, Feb 18, 2026 at 04:40:28PM +0300, Dmitry Antipov wrote:
> On Thu, 2026-02-12 at 19:44 +0300, Dmitry Antipov wrote:
>
> > Adjust '_parse_integer_limit()' and 'memparse()' to not ignore
> > overflows, extend string to 64-bit integer conversion tests, add
> > KUnit-based test for 'memparse()' and fix kernel-doc glitches
> > found in lib/cmdline.c.
> >
> > Dmitry Antipov (5):
> > lib: fix _parse_integer_limit() to handle overflow
> > lib: fix memparse() to handle overflow
> > lib: add more string to 64-bit integer conversion overflow tests
> > lib/cmdline_kunit: add test case for memparse()
> > lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
>
> Any chance to move forward with this?
I think it's a grace period due to ongoing merge window.
Also we need more input on the first patch from others,
perhaps Kees and Andrew can take a look when they will be
less busy.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 2/5] lib: fix memparse() to handle overflow
2026-02-12 16:44 ` [PATCH v8 2/5] lib: fix memparse() " Dmitry Antipov
@ 2026-02-24 12:32 ` Rodrigo Alencar
2026-02-24 14:15 ` Rodrigo Alencar
0 siblings, 1 reply; 15+ messages in thread
From: Rodrigo Alencar @ 2026-02-24 12:32 UTC (permalink / raw)
To: Dmitry Antipov, Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel
On 26/02/12 07:44PM, Dmitry Antipov wrote:
> Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now
> capable to handle overflow, adjust 'memparse()' to handle overflow
> (denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also
> use 'check_shl_overflow()' to catch an overflow possibly caused
> by processing size suffix and denote it with ULLONG_MAX as well.
is returning ULLONG_MAX the proper way to indicate overflow with
simple_strtoull()?
...
> unsigned long long memparse(const char *ptr, char **retptr)
> {
> char *endptr; /* local pointer to end of parsed string */
> -
> unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
... or a new wrapper for _parse_integer_limit() is needed?
I am interested on having _parse_integer_limit() overflow check
exposed to kernel modules.
...
--
Kind regards,
Rodrigo Alencar
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 2/5] lib: fix memparse() to handle overflow
2026-02-24 12:32 ` Rodrigo Alencar
@ 2026-02-24 14:15 ` Rodrigo Alencar
2026-02-25 6:58 ` Dmitry Antipov
0 siblings, 1 reply; 15+ messages in thread
From: Rodrigo Alencar @ 2026-02-24 14:15 UTC (permalink / raw)
To: Rodrigo Alencar, Dmitry Antipov, Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel
On 26/02/24 12:32PM, Rodrigo Alencar wrote:
> On 26/02/12 07:44PM, Dmitry Antipov wrote:
> > Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now
> > capable to handle overflow, adjust 'memparse()' to handle overflow
> > (denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also
> > use 'check_shl_overflow()' to catch an overflow possibly caused
> > by processing size suffix and denote it with ULLONG_MAX as well.
>
> is returning ULLONG_MAX the proper way to indicate overflow with
> simple_strtoull()?
>
> ...
>
> > unsigned long long memparse(const char *ptr, char **retptr)
> > {
> > char *endptr; /* local pointer to end of parsed string */
> > -
> > unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
>
> ... or a new wrapper for _parse_integer_limit() is needed?
>
> I am interested on having _parse_integer_limit() overflow check
> exposed to kernel modules.
> ...
I could propose the exposure of simple_strntoull() which is private
to lib/vsprintf.c, slightly changing its prototype:
* from:
unsigned long long simple_strntoull(const char *startp,
char **endp,
unsigned int base,
size_t max_chars)
* to:
int simple_strntoull(const char *startp,
char **endp,
unsigned long long *result,
unsigned int base,
size_t max_chars)
That would allow to tackle the FIXME tag. I suppose it is there
because the overflow flag is being ignored, so the returned integer
can be set to -ERANGE or -EOVERFLOW when overflow happens.
--
Kind regards,
Rodrigo Alencar
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 2/5] lib: fix memparse() to handle overflow
2026-02-24 14:15 ` Rodrigo Alencar
@ 2026-02-25 6:58 ` Dmitry Antipov
0 siblings, 0 replies; 15+ messages in thread
From: Dmitry Antipov @ 2026-02-25 6:58 UTC (permalink / raw)
To: Rodrigo Alencar, Andy Shevchenko, Andrew Morton
Cc: David Laight, Kees Cook, Darrick J . Wong, linux-hardening,
linux-kernel
On Tue, 2026-02-24 at 14:15 +0000, Rodrigo Alencar wrote:
> > I am interested on having _parse_integer_limit() overflow check
> > exposed to kernel modules.
Hm... _parse_integer_limit() may be EXPORT_SYMBOL()ed of course.
But are you sure that current API is not enough for your task?
> > ...
>
> I could propose the exposure of simple_strntoull() which is private
> to lib/vsprintf.c, slightly changing its prototype:
>
> * from:
> unsigned long long simple_strntoull(const char *startp,
> char **endp,
> unsigned int base,
> size_t max_chars)
> * to:
> int simple_strntoull(const char *startp,
> char **endp,
> unsigned long long *result,
> unsigned int base,
> size_t max_chars)
>
> That would allow to tackle the FIXME tag. I suppose it is there
> because the overflow flag is being ignored, so the returned integer
> can be set to -ERANGE or -EOVERFLOW when overflow happens.
Well, removal of KSTRTOX_OVERFLOW quirk may be a subject for the next series.
Dmitry
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-02-18 13:48 ` Andy Shevchenko
@ 2026-04-02 6:56 ` Dmitry Antipov
2026-04-02 8:30 ` Andy Shevchenko
0 siblings, 1 reply; 15+ messages in thread
From: Dmitry Antipov @ 2026-04-02 6:56 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Andrew Morton, David Laight, Kees Cook, Darrick J . Wong,
linux-hardening, linux-kernel
On Wed, 2026-02-18 at 15:48 +0200, Andy Shevchenko wrote:
> On Wed, Feb 18, 2026 at 04:40:28PM +0300, Dmitry Antipov wrote:
> > On Thu, 2026-02-12 at 19:44 +0300, Dmitry Antipov wrote:
> >
> > > Adjust '_parse_integer_limit()' and 'memparse()' to not ignore
> > > overflows, extend string to 64-bit integer conversion tests, add
> > > KUnit-based test for 'memparse()' and fix kernel-doc glitches
> > > found in lib/cmdline.c.
> > >
> > > Dmitry Antipov (5):
> > > lib: fix _parse_integer_limit() to handle overflow
> > > lib: fix memparse() to handle overflow
> > > lib: add more string to 64-bit integer conversion overflow tests
> > > lib/cmdline_kunit: add test case for memparse()
> > > lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
> >
> > Any chance to move forward with this?
>
> I think it's a grace period due to ongoing merge window.
> Also we need more input on the first patch from others,
> perhaps Kees and Andrew can take a look when they will be
> less busy.
The same question again...
Dmitry
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-04-02 6:56 ` Dmitry Antipov
@ 2026-04-02 8:30 ` Andy Shevchenko
2026-04-02 16:00 ` Andrew Morton
0 siblings, 1 reply; 15+ messages in thread
From: Andy Shevchenko @ 2026-04-02 8:30 UTC (permalink / raw)
To: Dmitry Antipov
Cc: Andrew Morton, David Laight, Kees Cook, Darrick J . Wong,
linux-hardening, linux-kernel
On Thu, Apr 02, 2026 at 09:56:45AM +0300, Dmitry Antipov wrote:
> On Wed, 2026-02-18 at 15:48 +0200, Andy Shevchenko wrote:
> > On Wed, Feb 18, 2026 at 04:40:28PM +0300, Dmitry Antipov wrote:
> > > On Thu, 2026-02-12 at 19:44 +0300, Dmitry Antipov wrote:
> > >
> > > > Adjust '_parse_integer_limit()' and 'memparse()' to not ignore
> > > > overflows, extend string to 64-bit integer conversion tests, add
> > > > KUnit-based test for 'memparse()' and fix kernel-doc glitches
> > > > found in lib/cmdline.c.
> > > >
> > > > Dmitry Antipov (5):
> > > > lib: fix _parse_integer_limit() to handle overflow
> > > > lib: fix memparse() to handle overflow
> > > > lib: add more string to 64-bit integer conversion overflow tests
> > > > lib/cmdline_kunit: add test case for memparse()
> > > > lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
> > >
> > > Any chance to move forward with this?
> >
> > I think it's a grace period due to ongoing merge window.
> > Also we need more input on the first patch from others,
> > perhaps Kees and Andrew can take a look when they will be
> > less busy.
>
> The same question again...
I'm not sure why. The patches are in Linux Next for several days already.
$ git tag --contains b85c7e022e1c # the last one
next-20260401
Yet it needs to be merged into nomm-stable (if I understood the process right).
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-04-02 8:30 ` Andy Shevchenko
@ 2026-04-02 16:00 ` Andrew Morton
2026-04-02 16:09 ` Andy Shevchenko
0 siblings, 1 reply; 15+ messages in thread
From: Andrew Morton @ 2026-04-02 16:00 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Dmitry Antipov, David Laight, Kees Cook, Darrick J . Wong,
linux-hardening, linux-kernel
On Thu, 2 Apr 2026 11:30:43 +0300 Andy Shevchenko <andriy.shevchenko@intel.com> wrote:
> > > > > lib/cmdline_kunit: add test case for memparse()
> > > > > lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
> > > >
> > > > Any chance to move forward with this?
> > >
> > > I think it's a grace period due to ongoing merge window.
> > > Also we need more input on the first patch from others,
> > > perhaps Kees and Andrew can take a look when they will be
> > > less busy.
> >
> > The same question again...
>
> I'm not sure why. The patches are in Linux Next for several days already.
> $ git tag --contains b85c7e022e1c # the last one
> next-20260401
>
> Yet it needs to be merged into nomm-stable (if I understood the process right).
Yes, these are on track for the upcoming merge window.
However I believe the riscv32 build breakage remains unresolved?
https://lore.kernel.org/all/202603041925.KLKqpK6N-lkp@intel.com/T/#u
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v8 0/5] lib and lib/cmdline enhancements
2026-04-02 16:00 ` Andrew Morton
@ 2026-04-02 16:09 ` Andy Shevchenko
0 siblings, 0 replies; 15+ messages in thread
From: Andy Shevchenko @ 2026-04-02 16:09 UTC (permalink / raw)
To: Andrew Morton
Cc: Dmitry Antipov, David Laight, Kees Cook, Darrick J . Wong,
linux-hardening, linux-kernel
On Thu, Apr 02, 2026 at 09:00:30AM -0700, Andrew Morton wrote:
> On Thu, 2 Apr 2026 11:30:43 +0300 Andy Shevchenko <andriy.shevchenko@intel.com> wrote:
> > > > > > lib/cmdline_kunit: add test case for memparse()
> > > > > > lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings
> > > > >
> > > > > Any chance to move forward with this?
> > > >
> > > > I think it's a grace period due to ongoing merge window.
> > > > Also we need more input on the first patch from others,
> > > > perhaps Kees and Andrew can take a look when they will be
> > > > less busy.
> > >
> > > The same question again...
> >
> > I'm not sure why. The patches are in Linux Next for several days already.
> > $ git tag --contains b85c7e022e1c # the last one
> > next-20260401
> >
> > Yet it needs to be merged into nomm-stable (if I understood the process right).
>
> Yes, these are on track for the upcoming merge window.
>
> However I believe the riscv32 build breakage remains unresolved?
>
> https://lore.kernel.org/all/202603041925.KLKqpK6N-lkp@intel.com/T/#u
I haven't heard any move of that. Ard proposed a fix/workaround. Nobody seems care.
So I think leaving it as is is also okay as risc-v people simply do not care.
Alternatively we may apply one of the suggested approaches: disabling EFI for 32-bit
or a patch that enables shift from a GCC library — in-kernel copy of it.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2026-04-02 16:09 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-02-12 16:44 [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 1/5] lib: fix _parse_integer_limit() to handle overflow Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 2/5] lib: fix memparse() " Dmitry Antipov
2026-02-24 12:32 ` Rodrigo Alencar
2026-02-24 14:15 ` Rodrigo Alencar
2026-02-25 6:58 ` Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 3/5] lib: add more string to 64-bit integer conversion overflow tests Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 4/5] lib/cmdline_kunit: add test case for memparse() Dmitry Antipov
2026-02-12 16:44 ` [PATCH v8 5/5] lib/cmdline: adjust a few comments to fix kernel-doc -Wreturn warnings Dmitry Antipov
2026-02-18 13:40 ` [PATCH v8 0/5] lib and lib/cmdline enhancements Dmitry Antipov
2026-02-18 13:48 ` Andy Shevchenko
2026-04-02 6:56 ` Dmitry Antipov
2026-04-02 8:30 ` Andy Shevchenko
2026-04-02 16:00 ` Andrew Morton
2026-04-02 16:09 ` Andy Shevchenko
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox