include/linux/string.h | 12 ++++++------ lib/string.c | 12 ++++++------ 2 files changed, 12 insertions(+), 12 deletions(-)
Source: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
Some functions in lib/string.c needs to use restrict according to sections:
* 7.21.2.1: memcpy
* 7.21.2.3: strcpy
* 7.21.2.4: strncpy
* 7.21.3.1: strcat
* 7.21.3.2: strncat
Signed-off-by: Guilhem Massol <guilhem.massol85@gmail.com>
---
include/linux/string.h | 12 ++++++------
lib/string.c | 12 ++++++------
2 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/include/linux/string.h b/include/linux/string.h
index b850bd91b3d8..07679485104b 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -65,12 +65,12 @@ void *vmemdup_array_user(const void __user *src, size_t n, size_t size)
#include <asm/string.h>
#ifndef __HAVE_ARCH_STRCPY
-extern char * strcpy(char *,const char *);
+extern char * strcpy(char *__restrict__, const char *__restrict__);
#endif
#ifndef __HAVE_ARCH_STRNCPY
-extern char * strncpy(char *,const char *, __kernel_size_t);
+extern char * strncpy(char *__restrict__, const char *__restrict__, __kernel_size_t);
#endif
-ssize_t sized_strscpy(char *, const char *, size_t);
+ssize_t sized_strscpy(char *__restrict__, const char *__restrict__, size_t);
/*
* The 2 argument style can only be used when dst is an array with a
@@ -149,10 +149,10 @@ ssize_t sized_strscpy(char *, const char *, size_t);
CONCATENATE(__strscpy_pad, COUNT_ARGS(__VA_ARGS__))(dst, src, __VA_ARGS__)
#ifndef __HAVE_ARCH_STRCAT
-extern char * strcat(char *, const char *);
+extern char * strcat(char *__restrict__, const char *__restrict__);
#endif
#ifndef __HAVE_ARCH_STRNCAT
-extern char * strncat(char *, const char *, __kernel_size_t);
+extern char * strncat(char *__restrict__, const char *__restrict__, __kernel_size_t);
#endif
#ifndef __HAVE_ARCH_STRLCAT
extern size_t strlcat(char *, const char *, __kernel_size_t);
@@ -257,7 +257,7 @@ extern void **__memcat_p(void **a, void **b);
})
#ifndef __HAVE_ARCH_MEMCPY
-extern void * memcpy(void *,const void *,__kernel_size_t);
+extern void * memcpy(void *__restrict__, const void *__restrict__, __kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMMOVE
extern void * memmove(void *,const void *,__kernel_size_t);
diff --git a/lib/string.c b/lib/string.c
index b632c71df1a5..9b492402ad04 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -77,7 +77,7 @@ EXPORT_SYMBOL(strcasecmp);
#endif
#ifndef __HAVE_ARCH_STRCPY
-char *strcpy(char *dest, const char *src)
+char *strcpy(char *__restrict__ dest, const char *__restrict__ src)
{
char *tmp = dest;
@@ -89,7 +89,7 @@ EXPORT_SYMBOL(strcpy);
#endif
#ifndef __HAVE_ARCH_STRNCPY
-char *strncpy(char *dest, const char *src, size_t count)
+char *strncpy(char *__restrict__ dest, const char *__restrict__ src, size_t count)
{
char *tmp = dest;
@@ -110,7 +110,7 @@ EXPORT_SYMBOL(strncpy);
# define ALLBUTLAST_BYTE_MASK (~0ul >> 8)
#endif
-ssize_t sized_strscpy(char *dest, const char *src, size_t count)
+ssize_t sized_strscpy(char *__restrict__ dest, const char *__restrict__ src, size_t count)
{
const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
size_t max = count;
@@ -215,7 +215,7 @@ char *stpcpy(char *__restrict__ dest, const char *__restrict__ src)
EXPORT_SYMBOL(stpcpy);
#ifndef __HAVE_ARCH_STRCAT
-char *strcat(char *dest, const char *src)
+char *strcat(char *__restrict__ dest, const char *__restrict__ src)
{
char *tmp = dest;
@@ -229,7 +229,7 @@ EXPORT_SYMBOL(strcat);
#endif
#ifndef __HAVE_ARCH_STRNCAT
-char *strncat(char *dest, const char *src, size_t count)
+char *strncat(char *__restrict__ dest, const char *__restrict__ src, size_t count)
{
char *tmp = dest;
@@ -618,7 +618,7 @@ EXPORT_SYMBOL(memset64);
* You should not use this function to access IO space, use memcpy_toio()
* or memcpy_fromio() instead.
*/
-void *memcpy(void *dest, const void *src, size_t count)
+void *memcpy(void *__restrict__ dest, const void *__restrict__ src, size_t count)
{
char *tmp = dest;
const char *s = src;
--
2.54.0Hi Guilhem,
kernel test robot noticed the following build warnings:
[auto build test WARNING on kees/for-next/hardening]
[also build test WARNING on linus/master v7.1-rc2 next-20260508]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Guilhem-Massol/string-Use-__restrict__-according-to-ISO-IEC-9899-TC3/20260505-025614
base: https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git for-next/hardening
patch link: https://lore.kernel.org/r/20260503131245.13868-1-guilhem.massol85%40gmail.com
patch subject: [PATCH] string: Use __restrict__ according to ISO/IEC 9899:TC3
config: microblaze-randconfig-r123-20260509 (https://download.01.org/0day-ci/archive/20260509/202605091039.FFdxv5Qe-lkp@intel.com/config)
compiler: microblaze-linux-gcc (GCC) 12.5.0
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260509/202605091039.FFdxv5Qe-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605091039.FFdxv5Qe-lkp@intel.com/
sparse warnings: (new ones prefixed by >>)
kernel/fork.c:1051:19: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct [noderef] __rcu *owner @@ got struct task_struct *p @@
kernel/fork.c:1051:19: sparse: expected struct task_struct [noderef] __rcu *owner
kernel/fork.c:1051:19: sparse: got struct task_struct *p
kernel/fork.c:1650:38: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct refcount_struct [usertype] *r @@ got struct refcount_struct [noderef] __rcu * @@
kernel/fork.c:1650:38: sparse: expected struct refcount_struct [usertype] *r
kernel/fork.c:1650:38: sparse: got struct refcount_struct [noderef] __rcu *
kernel/fork.c:1659:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:1659:31: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:1659:31: sparse: got struct spinlock [noderef] __rcu *
>> kernel/fork.c:1660:36: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected void const *restrict @@ got struct k_sigaction [noderef] __rcu * @@
kernel/fork.c:1660:36: sparse: expected void const *restrict
kernel/fork.c:1660:36: sparse: got struct k_sigaction [noderef] __rcu *
kernel/fork.c:1661:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:1661:33: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:1661:33: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2041:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2041:31: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2041:31: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2045:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2045:33: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2045:33: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2381:32: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct [noderef] __rcu *real_parent @@ got struct task_struct *register [addressable] [toplevel] current @@
kernel/fork.c:2381:32: sparse: expected struct task_struct [noderef] __rcu *real_parent
kernel/fork.c:2381:32: sparse: got struct task_struct *register [addressable] [toplevel] current
kernel/fork.c:2390:27: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2390:27: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2390:27: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2439:54: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct list_head *head @@ got struct list_head [noderef] __rcu * @@
kernel/fork.c:2439:54: sparse: expected struct list_head *head
kernel/fork.c:2439:54: sparse: got struct list_head [noderef] __rcu *
kernel/fork.c:2459:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2459:29: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2459:29: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2481:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2481:29: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2481:29: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2510:28: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct sighand_struct *sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/fork.c:2510:28: sparse: expected struct sighand_struct *sighand
kernel/fork.c:2510:28: sparse: got struct sighand_struct [noderef] __rcu *sighand
kernel/fork.c:2543:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2543:31: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2543:31: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2545:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/fork.c:2545:33: sparse: expected struct spinlock [usertype] *lock
kernel/fork.c:2545:33: sparse: got struct spinlock [noderef] __rcu *
kernel/fork.c:2984:24: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *[assigned] parent @@ got struct task_struct [noderef] __rcu *real_parent @@
kernel/fork.c:2984:24: sparse: expected struct task_struct *[assigned] parent
kernel/fork.c:2984:24: sparse: got struct task_struct [noderef] __rcu *real_parent
kernel/fork.c:3067:43: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct refcount_struct const [usertype] *r @@ got struct refcount_struct [noderef] __rcu * @@
kernel/fork.c:3067:43: sparse: expected struct refcount_struct const [usertype] *r
kernel/fork.c:3067:43: sparse: got struct refcount_struct [noderef] __rcu *
kernel/fork.c:1759:9: sparse: sparse: dereference of noderef expression
kernel/fork.c:2091:22: sparse: sparse: dereference of noderef expression
kernel/fork.c: note: in included file (through include/uapi/asm-generic/bpf_perf_event.h, arch/microblaze/include/generated/uapi/asm/bpf_perf_event.h, include/uapi/linux/bpf_perf_event.h, ...):
include/linux/ptrace.h:210:45: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct task_struct *new_parent @@ got struct task_struct [noderef] __rcu *parent @@
include/linux/ptrace.h:210:45: sparse: expected struct task_struct *new_parent
include/linux/ptrace.h:210:45: sparse: got struct task_struct [noderef] __rcu *parent
include/linux/ptrace.h:210:62: sparse: sparse: incorrect type in argument 3 (different address spaces) @@ expected struct cred const *ptracer_cred @@ got struct cred const [noderef] __rcu *ptracer_cred @@
include/linux/ptrace.h:210:62: sparse: expected struct cred const *ptracer_cred
include/linux/ptrace.h:210:62: sparse: got struct cred const [noderef] __rcu *ptracer_cred
kernel/fork.c:2437:59: sparse: sparse: dereference of noderef expression
kernel/fork.c:2438:59: sparse: sparse: dereference of noderef expression
kernel/fork.c:1043:23: sparse: sparse: incompatible types in comparison expression (different address spaces):
kernel/fork.c:1043:23: sparse: struct task_struct [noderef] __rcu *
kernel/fork.c:1043:23: sparse: struct task_struct *
--
>> drivers/mtd/nand/onenand/onenand_base.c:779:34: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected void const *restrict @@ got void [noderef] __iomem * @@
drivers/mtd/nand/onenand/onenand_base.c:779:34: sparse: expected void const *restrict
drivers/mtd/nand/onenand/onenand_base.c:779:34: sparse: got void [noderef] __iomem *
drivers/mtd/nand/onenand/onenand_base.c:817:34: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected void const *restrict @@ got void [noderef] __iomem * @@
drivers/mtd/nand/onenand/onenand_base.c:817:34: sparse: expected void const *restrict
drivers/mtd/nand/onenand/onenand_base.c:817:34: sparse: got void [noderef] __iomem *
>> drivers/mtd/nand/onenand/onenand_base.c:860:26: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void *restrict @@ got void [noderef] __iomem * @@
drivers/mtd/nand/onenand/onenand_base.c:860:26: sparse: expected void *restrict
drivers/mtd/nand/onenand/onenand_base.c:860:26: sparse: got void [noderef] __iomem *
vim +1660 kernel/fork.c
a016f3389c0660 JANAK DESAI 2006-02-07 1644
04ff48239f46e8 Simon Schuster 2025-09-01 1645 static int copy_sighand(u64 clone_flags, struct task_struct *tsk)
^1da177e4c3f41 Linus Torvalds 2005-04-16 1646 {
^1da177e4c3f41 Linus Torvalds 2005-04-16 1647 struct sighand_struct *sig;
^1da177e4c3f41 Linus Torvalds 2005-04-16 1648
60348802e9cb13 Zhaolei 2009-01-06 1649 if (clone_flags & CLONE_SIGHAND) {
d036bda7d0e726 Elena Reshetova 2019-01-18 1650 refcount_inc(¤t->sighand->count);
^1da177e4c3f41 Linus Torvalds 2005-04-16 1651 return 0;
^1da177e4c3f41 Linus Torvalds 2005-04-16 1652 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 1653 sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
0c282b068eb26d Madhuparna Bhowmik 2020-01-27 1654 RCU_INIT_POINTER(tsk->sighand, sig);
^1da177e4c3f41 Linus Torvalds 2005-04-16 1655 if (!sig)
^1da177e4c3f41 Linus Torvalds 2005-04-16 1656 return -ENOMEM;
9d7fb04276481c Peter Zijlstra 2015-06-30 1657
d036bda7d0e726 Elena Reshetova 2019-01-18 1658 refcount_set(&sig->count, 1);
06e62a46bbba20 Jann Horn 2018-08-21 1659 spin_lock_irq(¤t->sighand->siglock);
^1da177e4c3f41 Linus Torvalds 2005-04-16 @1660 memcpy(sig->action, current->sighand->action, sizeof(sig->action));
06e62a46bbba20 Jann Horn 2018-08-21 1661 spin_unlock_irq(¤t->sighand->siglock);
b612e5df4587c9 Christian Brauner 2019-10-14 1662
b612e5df4587c9 Christian Brauner 2019-10-14 1663 /* Reset all signal handler not set to SIG_IGN to SIG_DFL. */
b612e5df4587c9 Christian Brauner 2019-10-14 1664 if (clone_flags & CLONE_CLEAR_SIGHAND)
b612e5df4587c9 Christian Brauner 2019-10-14 1665 flush_signal_handlers(tsk, 0);
b612e5df4587c9 Christian Brauner 2019-10-14 1666
^1da177e4c3f41 Linus Torvalds 2005-04-16 1667 return 0;
^1da177e4c3f41 Linus Torvalds 2005-04-16 1668 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 1669
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
© 2016 - 2026 Red Hat, Inc.