Add a kstrndup function, modelled on strndup. Like strndup this returns a string copied into its own allocated memory, but it copies no more than the specified number of bytes from the source. Remove private strndup() from irda code. Signed-off-by: Jeremy Fitzhardinge Cc: Chris Wright Cc: Andrew Morton Cc: Randy Dunlap Cc: YOSHIFUJI Hideaki Cc: Akinobu Mita Cc: Arnaldo Carvalho de Melo Cc: Al Viro Cc: Panagiotis Issaris --- include/linux/string.h | 1 + mm/util.c | 30 +++++++++++++++++++++++++++--- net/irda/irias_object.c | 43 +++++-------------------------------------- 3 files changed, 33 insertions(+), 41 deletions(-) =================================================================== --- a/include/linux/string.h +++ b/include/linux/string.h @@ -105,6 +105,7 @@ extern void * memchr(const void *,int,__ #endif extern char *kstrdup(const char *s, gfp_t gfp); +extern char *kstrndup(const char *s, size_t len, gfp_t gfp); extern void *kmemdup(const void *src, size_t len, gfp_t gfp); #ifdef __cplusplus =================================================================== --- a/mm/util.c +++ b/mm/util.c @@ -18,9 +18,8 @@ void *__kzalloc(size_t size, gfp_t flags } EXPORT_SYMBOL(__kzalloc); -/* +/** * kstrdup - allocate space for and copy an existing string - * * @s: the string to duplicate * @gfp: the GFP mask used in the kmalloc() call when allocating memory */ @@ -39,6 +38,32 @@ char *kstrdup(const char *s, gfp_t gfp) return buf; } EXPORT_SYMBOL(kstrdup); + +/** + * kstrndup - allocate space for and copy an existing string + * @s: the string to duplicate + * @max: read at most @max chars from @s + * @gfp: the GFP mask used in the kmalloc() call when allocating memory + */ +char *kstrndup(const char *s, size_t max, gfp_t gfp) +{ + size_t len; + char *buf; + + if (!s) + return NULL; + + len = strlen(s); + if (len > max) + len = max; + buf = kmalloc_track_caller(len+1, gfp); + if (buf) { + memcpy(buf, s, len); + buf[len] = '\0'; + } + return buf; +} +EXPORT_SYMBOL(kstrndup); /** * kmemdup - duplicate region of memory @@ -60,7 +85,6 @@ EXPORT_SYMBOL(kmemdup); /* * strndup_user - duplicate an existing string from user space - * * @s: The string to duplicate * @n: Maximum number of bytes to copy, including the trailing NUL. */ =================================================================== --- a/net/irda/irias_object.c +++ b/net/irda/irias_object.c @@ -36,39 +36,6 @@ hashbin_t *irias_objects; */ struct ias_value irias_missing = { IAS_MISSING, 0, 0, 0, {0}}; -/* - * Function strndup (str, max) - * - * My own kernel version of strndup! - * - * Faster, check boundary... Jean II - */ -static char *strndup(char *str, size_t max) -{ - char *new_str; - int len; - - /* Check string */ - if (str == NULL) - return NULL; - /* Check length, truncate */ - len = strlen(str); - if(len > max) - len = max; - - /* Allocate new string */ - new_str = kmalloc(len + 1, GFP_ATOMIC); - if (new_str == NULL) { - IRDA_WARNING("%s: Unable to kmalloc!\n", __FUNCTION__); - return NULL; - } - - /* Copy and truncate */ - memcpy(new_str, str, len); - new_str[len] = '\0'; - - return new_str; -} /* * Function ias_new_object (name, id) @@ -90,7 +57,7 @@ struct ias_object *irias_new_object( cha } obj->magic = IAS_OBJECT_MAGIC; - obj->name = strndup(name, IAS_MAX_CLASSNAME); + obj->name = kstrndup(name, IAS_MAX_CLASSNAME, GFP_ATOMIC); if (!obj->name) { IRDA_WARNING("%s(), Unable to allocate name!\n", __FUNCTION__); @@ -360,7 +327,7 @@ void irias_add_integer_attrib(struct ias } attrib->magic = IAS_ATTRIB_MAGIC; - attrib->name = strndup(name, IAS_MAX_ATTRIBNAME); + attrib->name = kstrndup(name, IAS_MAX_ATTRIBNAME, GFP_ATOMIC); /* Insert value */ attrib->value = irias_new_integer_value(value); @@ -404,7 +371,7 @@ void irias_add_octseq_attrib(struct ias_ } attrib->magic = IAS_ATTRIB_MAGIC; - attrib->name = strndup(name, IAS_MAX_ATTRIBNAME); + attrib->name = kstrndup(name, IAS_MAX_ATTRIBNAME, GFP_ATOMIC); attrib->value = irias_new_octseq_value( octets, len); if (!attrib->name || !attrib->value) { @@ -446,7 +413,7 @@ void irias_add_string_attrib(struct ias_ } attrib->magic = IAS_ATTRIB_MAGIC; - attrib->name = strndup(name, IAS_MAX_ATTRIBNAME); + attrib->name = kstrndup(name, IAS_MAX_ATTRIBNAME, GFP_ATOMIC); attrib->value = irias_new_string_value(value); if (!attrib->name || !attrib->value) { @@ -506,7 +473,7 @@ struct ias_value *irias_new_string_value value->type = IAS_STRING; value->charset = CS_ASCII; - value->t.string = strndup(string, IAS_MAX_STRING); + value->t.string = kstrndup(string, IAS_MAX_STRING, GFP_ATOMIC); if (!value->t.string) { IRDA_WARNING("%s: Unable to kmalloc!\n", __FUNCTION__); kfree(value); -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/