korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-28 22:54:05 +08:00
Code Issues Packages Projects Releases Wiki Activity

cipso: Fix data-races around sysctl.

Browse Source 
While reading cipso sysctl variables, they can be changed concurrently.
So, we need to add READ_ONCE() to avoid data-races.

Fixes: 446fda4f26 ("[NetLabel]: CIPSOv4 engine")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Kuniyuki Iwashima 2022-07-06 16:40:01 -07:00 committed by David S. Miller
parent 310731e2f1
commit dd44f04b92
2 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Documentation/networking/ip-sysctl.rst
View File

@ -1085,7 +1085,7 @@ cipso_cache_enable - BOOLEAN
cipso_cache_bucket_size - INTEGER
The CIPSO label cache consists of a fixed size hash table with each
hash bucket containing a number of cache entries. This variable limits
the number of entries in each hash bucket; the larger the value the
the number of entries in each hash bucket; the larger the value is, the
more CIPSO label mappings that can be cached. When the number of
entries in a given hash bucket reaches this limit adding new entries
causes the oldest entry in the bucket to be removed to make room.

12
net/ipv4/cipso_ipv4.c
View File

@ -239,7 +239,7 @@ static int cipso_v4_cache_check(const unsigned char *key,
struct cipso_v4_map_cache_entry *prev_entry = NULL;
u32 hash;
if (!cipso_v4_cache_enabled)
if (!READ_ONCE(cipso_v4_cache_enabled))
return -ENOENT;
hash = cipso_v4_map_cache_hash(key, key_len);
@ -296,13 +296,14 @@ static int cipso_v4_cache_check(const unsigned char *key,
int cipso_v4_cache_add(const unsigned char *cipso_ptr,
const struct netlbl_lsm_secattr *secattr)
{
int bkt_size = READ_ONCE(cipso_v4_cache_bucketsize);
int ret_val = -EPERM;
u32 bkt;
struct cipso_v4_map_cache_entry *entry = NULL;
struct cipso_v4_map_cache_entry *old_entry = NULL;
u32 cipso_ptr_len;
if (!cipso_v4_cache_enabled || cipso_v4_cache_bucketsize <= 0)
if (!READ_ONCE(cipso_v4_cache_enabled) || bkt_size <= 0)
return 0;
cipso_ptr_len = cipso_ptr[1];
@ -322,7 +323,7 @@ int cipso_v4_cache_add(const unsigned char *cipso_ptr,
bkt = entry->hash & (CIPSO_V4_CACHE_BUCKETS - 1);
spin_lock_bh(&cipso_v4_cache[bkt].lock);
if (cipso_v4_cache[bkt].size < cipso_v4_cache_bucketsize) {
if (cipso_v4_cache[bkt].size < bkt_size) {
list_add(&entry->list, &cipso_v4_cache[bkt].list);
cipso_v4_cache[bkt].size += 1;
} else {
@ -1199,7 +1200,8 @@ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
/* This will send packets using the "optimized" format when
* possible as specified in section 3.4.2.6 of the
* CIPSO draft. */
if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10)
if (READ_ONCE(cipso_v4_rbm_optfmt) && ret_val > 0 &&
ret_val <= 10)
tag_len = 14;
else
tag_len = 4 + ret_val;
@ -1603,7 +1605,7 @@ int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
* all the CIPSO validations here but it doesn't
* really specify _exactly_ what we need to validate
* ... so, just make it a sysctl tunable. */
if (cipso_v4_rbm_strictvalid) {
if (READ_ONCE(cipso_v4_rbm_strictvalid)) {
if (cipso_v4_map_lvl_valid(doi_def,
tag[3]) < 0) {
err_offset = opt_iter + 3;