forked from luck/tmp_suning_uos_patched
net: Define usercopy region in struct proto slab cache
In support of usercopy hardening, this patch defines a region in the struct proto slab cache in which userspace copy operations are allowed. Some protocols need to copy objects to/from userspace, and they can declare the region via their proto structure with the new usersize and useroffset fields. Initially, if no region is specified (usersize == 0), the entire field is marked as whitelisted. This allows protocols to be whitelisted in subsequent patches. Once all protocols have been annotated, the full-whitelist default can be removed. This region is known as the slab cache's usercopy region. Slab caches can now check that each dynamically sized copy operation involving cache-managed memory falls entirely within the slab's usercopy region. This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY whitelisting code in the last public patch of grsecurity/PaX based on my understanding of the code. Changes or omissions from the original code are mine and don't reflect the original grsecurity/PaX code. Signed-off-by: David Windsor <dave@nullcore.net> [kees: adjust commit log, split off per-proto patches] [kees: add logic for by-default full-whitelist] Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
parent
0afe76e88c
commit
30c2c9f158
|
@ -1112,6 +1112,8 @@ struct proto {
|
|||
struct kmem_cache *slab;
|
||||
unsigned int obj_size;
|
||||
slab_flags_t slab_flags;
|
||||
size_t useroffset; /* Usercopy region offset */
|
||||
size_t usersize; /* Usercopy region size */
|
||||
|
||||
struct percpu_counter *orphan_count;
|
||||
|
||||
|
|
|
@ -3151,8 +3151,12 @@ static int req_prot_init(const struct proto *prot)
|
|||
int proto_register(struct proto *prot, int alloc_slab)
|
||||
{
|
||||
if (alloc_slab) {
|
||||
prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
|
||||
prot->slab = kmem_cache_create_usercopy(prot->name,
|
||||
prot->obj_size, 0,
|
||||
SLAB_HWCACHE_ALIGN | prot->slab_flags,
|
||||
prot->usersize ? prot->useroffset : 0,
|
||||
prot->usersize ? prot->usersize
|
||||
: prot->obj_size,
|
||||
NULL);
|
||||
|
||||
if (prot->slab == NULL) {
|
||||
|
|
Loading…
Reference in New Issue
Block a user