* [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc
[not found] <cover.1756793624.git.rongtao@cestc.cn>
@ 2025-09-02 6:17 ` Rong Tao
2025-09-02 7:08 ` Viktor Malik
2025-09-02 6:18 ` [PATCH bpf-next 2/2] selftests/bpf: Test kfunc bpf_strcasecmp Rong Tao
1 sibling, 1 reply; 5+ messages in thread
From: Rong Tao @ 2025-09-02 6:17 UTC (permalink / raw)
To: andrii, ast, vmalik
Cc: rtoax, Rong Tao, Daniel Borkmann, Martin KaFai Lau,
Eduard Zingerman, Song Liu, Yonghong Song, John Fastabend,
KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, Mykola Lysenko,
Shuah Khan,
open list:BPF [GENERAL] (Safe Dynamic Programs and Tools),
open list, open list:KERNEL SELFTEST FRAMEWORK
From: Rong Tao <rongtao@cestc.cn>
bpf_strcasecmp() function performs same like bpf_strcmp() except ignoring
the case of the characters.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
---
kernel/bpf/helpers.c | 56 +++++++++++++++++++++++++++++++++-----------
1 file changed, 42 insertions(+), 14 deletions(-)
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 401b4932cc49..e807a708e5fc 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -3349,20 +3349,7 @@ __bpf_kfunc void __bpf_trap(void)
* __get_kernel_nofault instead of plain dereference to make them safe.
*/
-/**
- * bpf_strcmp - Compare two strings
- * @s1__ign: One string
- * @s2__ign: Another string
- *
- * Return:
- * * %0 - Strings are equal
- * * %-1 - @s1__ign is smaller
- * * %1 - @s2__ign is smaller
- * * %-EFAULT - Cannot read one of the strings
- * * %-E2BIG - One of strings is too large
- * * %-ERANGE - One of strings is outside of kernel address space
- */
-__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
+int __bpf_strcasecmp(const char *s1__ign, const char *s2__ign, bool ignore_case)
{
char c1, c2;
int i;
@@ -3376,6 +3363,10 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
for (i = 0; i < XATTR_SIZE_MAX; i++) {
__get_kernel_nofault(&c1, s1__ign, char, err_out);
__get_kernel_nofault(&c2, s2__ign, char, err_out);
+ if (ignore_case) {
+ c1 = tolower(c1);
+ c2 = tolower(c2);
+ }
if (c1 != c2)
return c1 < c2 ? -1 : 1;
if (c1 == '\0')
@@ -3388,6 +3379,42 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
return -EFAULT;
}
+/**
+ * bpf_strcmp - Compare two strings
+ * @s1__ign: One string
+ * @s2__ign: Another string
+ *
+ * Return:
+ * * %0 - Strings are equal
+ * * %-1 - @s1__ign is smaller
+ * * %1 - @s2__ign is smaller
+ * * %-EFAULT - Cannot read one of the strings
+ * * %-E2BIG - One of strings is too large
+ * * %-ERANGE - One of strings is outside of kernel address space
+ */
+__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
+{
+ return __bpf_strcasecmp(s1__ign, s2__ign, false);
+}
+
+/**
+ * bpf_strcasecmp - Compare two strings, ignoring the case of the characters
+ * @s1__ign: One string
+ * @s2__ign: Another string
+ *
+ * Return:
+ * * %0 - Strings are equal
+ * * %-1 - @s1__ign is smaller
+ * * %1 - @s2__ign is smaller
+ * * %-EFAULT - Cannot read one of the strings
+ * * %-E2BIG - One of strings is too large
+ * * %-ERANGE - One of strings is outside of kernel address space
+ */
+__bpf_kfunc int bpf_strcasecmp(const char *s1__ign, const char *s2__ign)
+{
+ return __bpf_strcasecmp(s1__ign, s2__ign, true);
+}
+
/**
* bpf_strnchr - Find a character in a length limited string
* @s__ign: The string to be searched
@@ -3832,6 +3859,7 @@ BTF_ID_FLAGS(func, bpf_iter_dmabuf_destroy, KF_ITER_DESTROY | KF_SLEEPABLE)
#endif
BTF_ID_FLAGS(func, __bpf_trap)
BTF_ID_FLAGS(func, bpf_strcmp);
+BTF_ID_FLAGS(func, bpf_strcasecmp);
BTF_ID_FLAGS(func, bpf_strchr);
BTF_ID_FLAGS(func, bpf_strchrnul);
BTF_ID_FLAGS(func, bpf_strnchr);
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH bpf-next 2/2] selftests/bpf: Test kfunc bpf_strcasecmp
[not found] <cover.1756793624.git.rongtao@cestc.cn>
2025-09-02 6:17 ` [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc Rong Tao
@ 2025-09-02 6:18 ` Rong Tao
2025-09-02 7:12 ` Viktor Malik
1 sibling, 1 reply; 5+ messages in thread
From: Rong Tao @ 2025-09-02 6:18 UTC (permalink / raw)
To: andrii, ast, vmalik
Cc: rtoax, Rong Tao, Daniel Borkmann, Martin KaFai Lau,
Eduard Zingerman, Song Liu, Yonghong Song, John Fastabend,
KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, Mykola Lysenko,
Shuah Khan,
open list:BPF [GENERAL] (Safe Dynamic Programs and Tools),
open list, open list:KERNEL SELFTEST FRAMEWORK
From: Rong Tao <rongtao@cestc.cn>
Add testsuites for kfunc bpf_strcasecmp.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
---
tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c | 6 ++++++
tools/testing/selftests/bpf/progs/string_kfuncs_success.c | 5 +++++
2 files changed, 11 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
index 53af438bd998..99d72c68f76a 100644
--- a/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
+++ b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
@@ -31,6 +31,8 @@ char *invalid_kern_ptr = (char *)-1;
/* Passing NULL to string kfuncs (treated as a userspace ptr) */
SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_null1(void *ctx) { return bpf_strcmp(NULL, "hello"); }
SEC("syscall") __retval(USER_PTR_ERR)int test_strcmp_null2(void *ctx) { return bpf_strcmp("hello", NULL); }
+SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_null1(void *ctx) { return bpf_strcasecmp(NULL, "HELLO"); }
+SEC("syscall") __retval(USER_PTR_ERR)int test_strcasecmp_null2(void *ctx) { return bpf_strcasecmp("HELLO", NULL); }
SEC("syscall") __retval(USER_PTR_ERR)int test_strchr_null(void *ctx) { return bpf_strchr(NULL, 'a'); }
SEC("syscall") __retval(USER_PTR_ERR)int test_strchrnul_null(void *ctx) { return bpf_strchrnul(NULL, 'a'); }
SEC("syscall") __retval(USER_PTR_ERR)int test_strnchr_null(void *ctx) { return bpf_strnchr(NULL, 1, 'a'); }
@@ -49,6 +51,8 @@ SEC("syscall") __retval(USER_PTR_ERR)int test_strnstr_null2(void *ctx) { return
/* Passing userspace ptr to string kfuncs */
SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr1(void *ctx) { return bpf_strcmp(user_ptr, "hello"); }
SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr2(void *ctx) { return bpf_strcmp("hello", user_ptr); }
+SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_user_ptr1(void *ctx) { return bpf_strcasecmp(user_ptr, "HELLO"); }
+SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_user_ptr2(void *ctx) { return bpf_strcasecmp("HELLO", user_ptr); }
SEC("syscall") __retval(USER_PTR_ERR) int test_strchr_user_ptr(void *ctx) { return bpf_strchr(user_ptr, 'a'); }
SEC("syscall") __retval(USER_PTR_ERR) int test_strchrnul_user_ptr(void *ctx) { return bpf_strchrnul(user_ptr, 'a'); }
SEC("syscall") __retval(USER_PTR_ERR) int test_strnchr_user_ptr(void *ctx) { return bpf_strnchr(user_ptr, 1, 'a'); }
@@ -69,6 +73,8 @@ SEC("syscall") __retval(USER_PTR_ERR) int test_strnstr_user_ptr2(void *ctx) { re
/* Passing invalid kernel ptr to string kfuncs should always return -EFAULT */
SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault1(void *ctx) { return bpf_strcmp(invalid_kern_ptr, "hello"); }
SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault2(void *ctx) { return bpf_strcmp("hello", invalid_kern_ptr); }
+SEC("syscall") __retval(-EFAULT) int test_strcasecmp_pagefault1(void *ctx) { return bpf_strcasecmp(invalid_kern_ptr, "HELLO"); }
+SEC("syscall") __retval(-EFAULT) int test_strcasecmp_pagefault2(void *ctx) { return bpf_strcasecmp("HELLO", invalid_kern_ptr); }
SEC("syscall") __retval(-EFAULT) int test_strchr_pagefault(void *ctx) { return bpf_strchr(invalid_kern_ptr, 'a'); }
SEC("syscall") __retval(-EFAULT) int test_strchrnul_pagefault(void *ctx) { return bpf_strchrnul(invalid_kern_ptr, 'a'); }
SEC("syscall") __retval(-EFAULT) int test_strnchr_pagefault(void *ctx) { return bpf_strnchr(invalid_kern_ptr, 1, 'a'); }
diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_success.c b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
index 46697f381878..67830456637b 100644
--- a/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
+++ b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
@@ -12,6 +12,11 @@ char str[] = "hello world";
/* Functional tests */
__test(0) int test_strcmp_eq(void *ctx) { return bpf_strcmp(str, "hello world"); }
__test(1) int test_strcmp_neq(void *ctx) { return bpf_strcmp(str, "hello"); }
+__test(0) int test_strcasecmp_eq1(void *ctx) { return bpf_strcasecmp(str, "hello world"); }
+__test(0) int test_strcasecmp_eq2(void *ctx) { return bpf_strcasecmp(str, "HELLO WORLD"); }
+__test(0) int test_strcasecmp_eq3(void *ctx) { return bpf_strcasecmp(str, "HELLO world"); }
+__test(1) int test_strcasecmp_neq1(void *ctx) { return bpf_strcasecmp(str, "hello"); }
+__test(1) int test_strcasecmp_neq2(void *ctx) { return bpf_strcasecmp(str, "HELLO"); }
__test(1) int test_strchr_found(void *ctx) { return bpf_strchr(str, 'e'); }
__test(11) int test_strchr_null(void *ctx) { return bpf_strchr(str, '\0'); }
__test(-ENOENT) int test_strchr_notfound(void *ctx) { return bpf_strchr(str, 'x'); }
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc
2025-09-02 6:17 ` [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc Rong Tao
@ 2025-09-02 7:08 ` Viktor Malik
2025-09-02 7:14 ` Rong Tao
0 siblings, 1 reply; 5+ messages in thread
From: Viktor Malik @ 2025-09-02 7:08 UTC (permalink / raw)
To: Rong Tao, andrii, ast
Cc: Rong Tao, Daniel Borkmann, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, John Fastabend, KP Singh,
Stanislav Fomichev, Hao Luo, Jiri Olsa, Mykola Lysenko,
Shuah Khan,
open list:BPF [GENERAL] (Safe Dynamic Programs and Tools),
open list, open list:KERNEL SELFTEST FRAMEWORK
On 9/2/25 08:17, Rong Tao wrote:
> From: Rong Tao <rongtao@cestc.cn>
>
> bpf_strcasecmp() function performs same like bpf_strcmp() except ignoring
> the case of the characters.
>
> Signed-off-by: Rong Tao <rongtao@cestc.cn>
> ---
> kernel/bpf/helpers.c | 56 +++++++++++++++++++++++++++++++++-----------
> 1 file changed, 42 insertions(+), 14 deletions(-)
>
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index 401b4932cc49..e807a708e5fc 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -3349,20 +3349,7 @@ __bpf_kfunc void __bpf_trap(void)
> * __get_kernel_nofault instead of plain dereference to make them safe.
> */
>
> -/**
> - * bpf_strcmp - Compare two strings
> - * @s1__ign: One string
> - * @s2__ign: Another string
> - *
> - * Return:
> - * * %0 - Strings are equal
> - * * %-1 - @s1__ign is smaller
> - * * %1 - @s2__ign is smaller
> - * * %-EFAULT - Cannot read one of the strings
> - * * %-E2BIG - One of strings is too large
> - * * %-ERANGE - One of strings is outside of kernel address space
> - */
> -__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
> +int __bpf_strcasecmp(const char *s1__ign, const char *s2__ign, bool ignore_case)
No need to use the `__ign` suffix here.
Otherwise LGTM. I guess that it could be useful in some applications.
Viktor
> {
> char c1, c2;
> int i;
> @@ -3376,6 +3363,10 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
> for (i = 0; i < XATTR_SIZE_MAX; i++) {
> __get_kernel_nofault(&c1, s1__ign, char, err_out);
> __get_kernel_nofault(&c2, s2__ign, char, err_out);
> + if (ignore_case) {
> + c1 = tolower(c1);
> + c2 = tolower(c2);
> + }
> if (c1 != c2)
> return c1 < c2 ? -1 : 1;
> if (c1 == '\0')
> @@ -3388,6 +3379,42 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
> return -EFAULT;
> }
>
> +/**
> + * bpf_strcmp - Compare two strings
> + * @s1__ign: One string
> + * @s2__ign: Another string
> + *
> + * Return:
> + * * %0 - Strings are equal
> + * * %-1 - @s1__ign is smaller
> + * * %1 - @s2__ign is smaller
> + * * %-EFAULT - Cannot read one of the strings
> + * * %-E2BIG - One of strings is too large
> + * * %-ERANGE - One of strings is outside of kernel address space
> + */
> +__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
> +{
> + return __bpf_strcasecmp(s1__ign, s2__ign, false);
> +}
> +
> +/**
> + * bpf_strcasecmp - Compare two strings, ignoring the case of the characters
> + * @s1__ign: One string
> + * @s2__ign: Another string
> + *
> + * Return:
> + * * %0 - Strings are equal
> + * * %-1 - @s1__ign is smaller
> + * * %1 - @s2__ign is smaller
> + * * %-EFAULT - Cannot read one of the strings
> + * * %-E2BIG - One of strings is too large
> + * * %-ERANGE - One of strings is outside of kernel address space
> + */
> +__bpf_kfunc int bpf_strcasecmp(const char *s1__ign, const char *s2__ign)
> +{
> + return __bpf_strcasecmp(s1__ign, s2__ign, true);
> +}
> +
> /**
> * bpf_strnchr - Find a character in a length limited string
> * @s__ign: The string to be searched
> @@ -3832,6 +3859,7 @@ BTF_ID_FLAGS(func, bpf_iter_dmabuf_destroy, KF_ITER_DESTROY | KF_SLEEPABLE)
> #endif
> BTF_ID_FLAGS(func, __bpf_trap)
> BTF_ID_FLAGS(func, bpf_strcmp);
> +BTF_ID_FLAGS(func, bpf_strcasecmp);
> BTF_ID_FLAGS(func, bpf_strchr);
> BTF_ID_FLAGS(func, bpf_strchrnul);
> BTF_ID_FLAGS(func, bpf_strnchr);
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH bpf-next 2/2] selftests/bpf: Test kfunc bpf_strcasecmp
2025-09-02 6:18 ` [PATCH bpf-next 2/2] selftests/bpf: Test kfunc bpf_strcasecmp Rong Tao
@ 2025-09-02 7:12 ` Viktor Malik
0 siblings, 0 replies; 5+ messages in thread
From: Viktor Malik @ 2025-09-02 7:12 UTC (permalink / raw)
To: Rong Tao, andrii, ast
Cc: Rong Tao, Daniel Borkmann, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, John Fastabend, KP Singh,
Stanislav Fomichev, Hao Luo, Jiri Olsa, Mykola Lysenko,
Shuah Khan,
open list:BPF [GENERAL] (Safe Dynamic Programs and Tools),
open list, open list:KERNEL SELFTEST FRAMEWORK
On 9/2/25 08:18, Rong Tao wrote:
> From: Rong Tao <rongtao@cestc.cn>
>
> Add testsuites for kfunc bpf_strcasecmp.
>
> Signed-off-by: Rong Tao <rongtao@cestc.cn>
> ---
> tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c | 6 ++++++
> tools/testing/selftests/bpf/progs/string_kfuncs_success.c | 5 +++++
> 2 files changed, 11 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
> index 53af438bd998..99d72c68f76a 100644
> --- a/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
> +++ b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c
> @@ -31,6 +31,8 @@ char *invalid_kern_ptr = (char *)-1;
> /* Passing NULL to string kfuncs (treated as a userspace ptr) */
> SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_null1(void *ctx) { return bpf_strcmp(NULL, "hello"); }
> SEC("syscall") __retval(USER_PTR_ERR)int test_strcmp_null2(void *ctx) { return bpf_strcmp("hello", NULL); }
> +SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_null1(void *ctx) { return bpf_strcasecmp(NULL, "HELLO"); }
> +SEC("syscall") __retval(USER_PTR_ERR)int test_strcasecmp_null2(void *ctx) { return bpf_strcasecmp("HELLO", NULL); }
> SEC("syscall") __retval(USER_PTR_ERR)int test_strchr_null(void *ctx) { return bpf_strchr(NULL, 'a'); }
> SEC("syscall") __retval(USER_PTR_ERR)int test_strchrnul_null(void *ctx) { return bpf_strchrnul(NULL, 'a'); }
> SEC("syscall") __retval(USER_PTR_ERR)int test_strnchr_null(void *ctx) { return bpf_strnchr(NULL, 1, 'a'); }
> @@ -49,6 +51,8 @@ SEC("syscall") __retval(USER_PTR_ERR)int test_strnstr_null2(void *ctx) { return
> /* Passing userspace ptr to string kfuncs */
> SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr1(void *ctx) { return bpf_strcmp(user_ptr, "hello"); }
> SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr2(void *ctx) { return bpf_strcmp("hello", user_ptr); }
> +SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_user_ptr1(void *ctx) { return bpf_strcasecmp(user_ptr, "HELLO"); }
> +SEC("syscall") __retval(USER_PTR_ERR) int test_strcasecmp_user_ptr2(void *ctx) { return bpf_strcasecmp("HELLO", user_ptr); }
> SEC("syscall") __retval(USER_PTR_ERR) int test_strchr_user_ptr(void *ctx) { return bpf_strchr(user_ptr, 'a'); }
> SEC("syscall") __retval(USER_PTR_ERR) int test_strchrnul_user_ptr(void *ctx) { return bpf_strchrnul(user_ptr, 'a'); }
> SEC("syscall") __retval(USER_PTR_ERR) int test_strnchr_user_ptr(void *ctx) { return bpf_strnchr(user_ptr, 1, 'a'); }
> @@ -69,6 +73,8 @@ SEC("syscall") __retval(USER_PTR_ERR) int test_strnstr_user_ptr2(void *ctx) { re
> /* Passing invalid kernel ptr to string kfuncs should always return -EFAULT */
> SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault1(void *ctx) { return bpf_strcmp(invalid_kern_ptr, "hello"); }
> SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault2(void *ctx) { return bpf_strcmp("hello", invalid_kern_ptr); }
> +SEC("syscall") __retval(-EFAULT) int test_strcasecmp_pagefault1(void *ctx) { return bpf_strcasecmp(invalid_kern_ptr, "HELLO"); }
> +SEC("syscall") __retval(-EFAULT) int test_strcasecmp_pagefault2(void *ctx) { return bpf_strcasecmp("HELLO", invalid_kern_ptr); }
> SEC("syscall") __retval(-EFAULT) int test_strchr_pagefault(void *ctx) { return bpf_strchr(invalid_kern_ptr, 'a'); }
> SEC("syscall") __retval(-EFAULT) int test_strchrnul_pagefault(void *ctx) { return bpf_strchrnul(invalid_kern_ptr, 'a'); }
> SEC("syscall") __retval(-EFAULT) int test_strnchr_pagefault(void *ctx) { return bpf_strnchr(invalid_kern_ptr, 1, 'a'); }
> diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_success.c b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
> index 46697f381878..67830456637b 100644
> --- a/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
> +++ b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c
> @@ -12,6 +12,11 @@ char str[] = "hello world";
> /* Functional tests */
> __test(0) int test_strcmp_eq(void *ctx) { return bpf_strcmp(str, "hello world"); }
> __test(1) int test_strcmp_neq(void *ctx) { return bpf_strcmp(str, "hello"); }
> +__test(0) int test_strcasecmp_eq1(void *ctx) { return bpf_strcasecmp(str, "hello world"); }
> +__test(0) int test_strcasecmp_eq2(void *ctx) { return bpf_strcasecmp(str, "HELLO WORLD"); }
> +__test(0) int test_strcasecmp_eq3(void *ctx) { return bpf_strcasecmp(str, "HELLO world"); }
> +__test(1) int test_strcasecmp_neq1(void *ctx) { return bpf_strcasecmp(str, "hello"); }
> +__test(1) int test_strcasecmp_neq2(void *ctx) { return bpf_strcasecmp(str, "HELLO"); }
> __test(1) int test_strchr_found(void *ctx) { return bpf_strchr(str, 'e'); }
> __test(11) int test_strchr_null(void *ctx) { return bpf_strchr(str, '\0'); }
> __test(-ENOENT) int test_strchr_notfound(void *ctx) { return bpf_strchr(str, 'x'); }
Missing a test for returning -E2BIG in
tools/testing/selftests/bpf/progs/string_kfuncs_failure2.c.
Viktor
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc
2025-09-02 7:08 ` Viktor Malik
@ 2025-09-02 7:14 ` Rong Tao
0 siblings, 0 replies; 5+ messages in thread
From: Rong Tao @ 2025-09-02 7:14 UTC (permalink / raw)
To: Viktor Malik, andrii, ast
Cc: Rong Tao, Daniel Borkmann, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, John Fastabend, KP Singh,
Stanislav Fomichev, Hao Luo, Jiri Olsa, Mykola Lysenko,
Shuah Khan,
open list:BPF [GENERAL] (Safe Dynamic Programs and Tools),
open list, open list:KERNEL SELFTEST FRAMEWORK
On 9/2/25 15:08, Viktor Malik wrote:
> On 9/2/25 08:17, Rong Tao wrote:
>> From: Rong Tao <rongtao@cestc.cn>
>>
>> bpf_strcasecmp() function performs same like bpf_strcmp() except ignoring
>> the case of the characters.
>>
>> Signed-off-by: Rong Tao <rongtao@cestc.cn>
>> ---
>> kernel/bpf/helpers.c | 56 +++++++++++++++++++++++++++++++++-----------
>> 1 file changed, 42 insertions(+), 14 deletions(-)
>>
>> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
>> index 401b4932cc49..e807a708e5fc 100644
>> --- a/kernel/bpf/helpers.c
>> +++ b/kernel/bpf/helpers.c
>> @@ -3349,20 +3349,7 @@ __bpf_kfunc void __bpf_trap(void)
>> * __get_kernel_nofault instead of plain dereference to make them safe.
>> */
>>
>> -/**
>> - * bpf_strcmp - Compare two strings
>> - * @s1__ign: One string
>> - * @s2__ign: Another string
>> - *
>> - * Return:
>> - * * %0 - Strings are equal
>> - * * %-1 - @s1__ign is smaller
>> - * * %1 - @s2__ign is smaller
>> - * * %-EFAULT - Cannot read one of the strings
>> - * * %-E2BIG - One of strings is too large
>> - * * %-ERANGE - One of strings is outside of kernel address space
>> - */
>> -__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
>> +int __bpf_strcasecmp(const char *s1__ign, const char *s2__ign, bool ignore_case)
> No need to use the `__ign` suffix here.
Viktor, Thanks for your review, i'll submit v2 soon.
Rong Tao
>
> Otherwise LGTM. I guess that it could be useful in some applications.
>
> Viktor
>
>> {
>> char c1, c2;
>> int i;
>> @@ -3376,6 +3363,10 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
>> for (i = 0; i < XATTR_SIZE_MAX; i++) {
>> __get_kernel_nofault(&c1, s1__ign, char, err_out);
>> __get_kernel_nofault(&c2, s2__ign, char, err_out);
>> + if (ignore_case) {
>> + c1 = tolower(c1);
>> + c2 = tolower(c2);
>> + }
>> if (c1 != c2)
>> return c1 < c2 ? -1 : 1;
>> if (c1 == '\0')
>> @@ -3388,6 +3379,42 @@ __bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
>> return -EFAULT;
>> }
>>
>> +/**
>> + * bpf_strcmp - Compare two strings
>> + * @s1__ign: One string
>> + * @s2__ign: Another string
>> + *
>> + * Return:
>> + * * %0 - Strings are equal
>> + * * %-1 - @s1__ign is smaller
>> + * * %1 - @s2__ign is smaller
>> + * * %-EFAULT - Cannot read one of the strings
>> + * * %-E2BIG - One of strings is too large
>> + * * %-ERANGE - One of strings is outside of kernel address space
>> + */
>> +__bpf_kfunc int bpf_strcmp(const char *s1__ign, const char *s2__ign)
>> +{
>> + return __bpf_strcasecmp(s1__ign, s2__ign, false);
>> +}
>> +
>> +/**
>> + * bpf_strcasecmp - Compare two strings, ignoring the case of the characters
>> + * @s1__ign: One string
>> + * @s2__ign: Another string
>> + *
>> + * Return:
>> + * * %0 - Strings are equal
>> + * * %-1 - @s1__ign is smaller
>> + * * %1 - @s2__ign is smaller
>> + * * %-EFAULT - Cannot read one of the strings
>> + * * %-E2BIG - One of strings is too large
>> + * * %-ERANGE - One of strings is outside of kernel address space
>> + */
>> +__bpf_kfunc int bpf_strcasecmp(const char *s1__ign, const char *s2__ign)
>> +{
>> + return __bpf_strcasecmp(s1__ign, s2__ign, true);
>> +}
>> +
>> /**
>> * bpf_strnchr - Find a character in a length limited string
>> * @s__ign: The string to be searched
>> @@ -3832,6 +3859,7 @@ BTF_ID_FLAGS(func, bpf_iter_dmabuf_destroy, KF_ITER_DESTROY | KF_SLEEPABLE)
>> #endif
>> BTF_ID_FLAGS(func, __bpf_trap)
>> BTF_ID_FLAGS(func, bpf_strcmp);
>> +BTF_ID_FLAGS(func, bpf_strcasecmp);
>> BTF_ID_FLAGS(func, bpf_strchr);
>> BTF_ID_FLAGS(func, bpf_strchrnul);
>> BTF_ID_FLAGS(func, bpf_strnchr);
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2025-09-02 7:14 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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[not found] <cover.1756793624.git.rongtao@cestc.cn>
2025-09-02 6:17 ` [PATCH bpf-next 1/2] bpf: add bpf_strcasecmp kfunc Rong Tao
2025-09-02 7:08 ` Viktor Malik
2025-09-02 7:14 ` Rong Tao
2025-09-02 6:18 ` [PATCH bpf-next 2/2] selftests/bpf: Test kfunc bpf_strcasecmp Rong Tao
2025-09-02 7:12 ` Viktor Malik
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