2013-08-20 03:18:08

by Chen Gang

Subject: [PATCH] kernel/params.c: use scnprintf() instead of sprintf()

For some strings (e.g. version string), they are permitted to be larger
than PAGE_SIZE (although meaningless), so recommend to use scnprintf()
instead of sprintf().


Signed-off-by: Chen Gang <[email protected]>
---
kernel/params.c | 7 ++++---
1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/params.c b/kernel/params.c
index 1f228a3..4da300f 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -241,7 +241,8 @@ int parse_args(const char *doing,
} \
int param_get_##name(char *buffer, const struct kernel_param *kp) \
{ \
- return sprintf(buffer, format, *((type *)kp->arg)); \
+ return scnprintf(buffer, PAGE_SIZE, format, \
+ *((type *)kp->arg)); \
} \
struct kernel_param_ops param_ops_##name = { \
.set = param_set_##name, \
@@ -285,7 +286,7 @@ EXPORT_SYMBOL(param_set_charp);

int param_get_charp(char *buffer, const struct kernel_param *kp)
{
- return sprintf(buffer, "%s", *((char **)kp->arg));
+ return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
}
EXPORT_SYMBOL(param_get_charp);

@@ -827,7 +828,7 @@ ssize_t __modver_version_show(struct module_attribute *mattr,
struct module_version_attribute *vattr =
container_of(mattr, struct module_version_attribute, mattr);

- return sprintf(buf, "%s\n", vattr->version);
+ return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
}

extern const struct module_version_attribute *__start___modver[];
--
1.7.7.6

2013-08-21 01:17:50

by Rusty Russell

Subject: Re: [PATCH] kernel/params.c: use scnprintf() instead of sprintf()

Chen Gang <[email protected]> writes:

> For some strings (e.g. version string), they are permitted to be larger
> than PAGE_SIZE (although meaningless), so recommend to use scnprintf()
> instead of sprintf().

Applied.

Thanks,
Rusty.

>
> Signed-off-by: Chen Gang <[email protected]>
> ---
> kernel/params.c | 7 ++++---
> 1 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/params.c b/kernel/params.c
> index 1f228a3..4da300f 100644
> --- a/kernel/params.c
> +++ b/kernel/params.c
> @@ -241,7 +241,8 @@ int parse_args(const char *doing,
> } \
> int param_get_##name(char *buffer, const struct kernel_param *kp) \
> { \
> - return sprintf(buffer, format, *((type *)kp->arg)); \
> + return scnprintf(buffer, PAGE_SIZE, format, \
> + *((type *)kp->arg)); \
> } \
> struct kernel_param_ops param_ops_##name = { \
> .set = param_set_##name, \
> @@ -285,7 +286,7 @@ EXPORT_SYMBOL(param_set_charp);
>
> int param_get_charp(char *buffer, const struct kernel_param *kp)
> {
> - return sprintf(buffer, "%s", *((char **)kp->arg));
> + return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
> }
> EXPORT_SYMBOL(param_get_charp);
>
> @@ -827,7 +828,7 @@ ssize_t __modver_version_show(struct module_attribute *mattr,
> struct module_version_attribute *vattr =
> container_of(mattr, struct module_version_attribute, mattr);
>
> - return sprintf(buf, "%s\n", vattr->version);
> + return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
> }
>
> extern const struct module_version_attribute *__start___modver[];
> --
> 1.7.7.6

2013-08-21 02:05:47

by Chen Gang

Subject: Re: [PATCH] kernel/params.c: use scnprintf() instead of sprintf()

On 08/20/2013 02:05 PM, Rusty Russell wrote:
> Chen Gang <[email protected]> writes:
>
>> For some strings (e.g. version string), they are permitted to be larger
>> than PAGE_SIZE (although meaningless), so recommend to use scnprintf()
>> instead of sprintf().
>
> Applied.
>

Thanks.

> Thanks,
> Rusty.
>
>>
>> Signed-off-by: Chen Gang <[email protected]>
>> ---
>> kernel/params.c | 7 ++++---
>> 1 files changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/kernel/params.c b/kernel/params.c
>> index 1f228a3..4da300f 100644
>> --- a/kernel/params.c
>> +++ b/kernel/params.c
>> @@ -241,7 +241,8 @@ int parse_args(const char *doing,
>> } \
>> int param_get_##name(char *buffer, const struct kernel_param *kp) \
>> { \
>> - return sprintf(buffer, format, *((type *)kp->arg)); \
>> + return scnprintf(buffer, PAGE_SIZE, format, \
>> + *((type *)kp->arg)); \
>> } \
>> struct kernel_param_ops param_ops_##name = { \
>> .set = param_set_##name, \
>> @@ -285,7 +286,7 @@ EXPORT_SYMBOL(param_set_charp);
>>
>> int param_get_charp(char *buffer, const struct kernel_param *kp)
>> {
>> - return sprintf(buffer, "%s", *((char **)kp->arg));
>> + return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
>> }
>> EXPORT_SYMBOL(param_get_charp);
>>
>> @@ -827,7 +828,7 @@ ssize_t __modver_version_show(struct module_attribute *mattr,
>> struct module_version_attribute *vattr =
>> container_of(mattr, struct module_version_attribute, mattr);
>>
>> - return sprintf(buf, "%s\n", vattr->version);
>> + return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
>> }
>>
>> extern const struct module_version_attribute *__start___modver[];
>> --
>> 1.7.7.6
>
>


--
Chen Gang