As part of the work to perform bounds checking on all memcpy() uses, replace the open-coded a deserialization of bytes out of memory into a trailing flexible array by using a flex_array.h helper to perform the allocation, bounds checking, and copying. Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: Paolo Abeni <pabeni@xxxxxxxxxx> Cc: Yang Yingliang <yangyingliang@xxxxxxxxxx> Cc: netdev@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- include/net/mrp.h | 4 ++-- net/802/mrp.c | 9 +++------ 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/include/net/mrp.h b/include/net/mrp.h index 1c308c034e1a..211670bb46f2 100644 --- a/include/net/mrp.h +++ b/include/net/mrp.h @@ -91,8 +91,8 @@ struct mrp_attr { struct rb_node node; enum mrp_applicant_state state; u8 type; - u8 len; - unsigned char value[]; + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(u8, len); + DECLARE_FLEX_ARRAY_ELEMENTS(unsigned char, value); }; enum mrp_applications { diff --git a/net/802/mrp.c b/net/802/mrp.c index 35e04cc5390c..8b9b2e685a42 100644 --- a/net/802/mrp.c +++ b/net/802/mrp.c @@ -257,7 +257,7 @@ static struct mrp_attr *mrp_attr_create(struct mrp_applicant *app, const void *value, u8 len, u8 type) { struct rb_node *parent = NULL, **p = &app->mad.rb_node; - struct mrp_attr *attr; + struct mrp_attr *attr = NULL; int d; while (*p) { @@ -273,13 +273,10 @@ static struct mrp_attr *mrp_attr_create(struct mrp_applicant *app, return attr; } } - attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC); - if (!attr) - return attr; + if (mem_to_flex_dup(&attr, value, len, GFP_ATOMIC)) + return NULL; attr->state = MRP_APPLICANT_VO; attr->type = type; - attr->len = len; - memcpy(attr->value, value, len); rb_link_node(&attr->node, parent, p); rb_insert_color(&attr->node, &app->mad); -- 2.32.0