ratelimit: Fix data-races in ___ratelimit().
While reading rs->interval and rs->burst, they can be changed
concurrently via sysctl (e.g. net_ratelimit_state). Thus, we
need to add READ_ONCE() to their readers.
Fixes: 1da177e4c3
("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
61adf447e3
commit
6bae8ceb90
|
@ -26,10 +26,16 @@
|
|||
*/
|
||||
int ___ratelimit(struct ratelimit_state *rs, const char *func)
|
||||
{
|
||||
/* Paired with WRITE_ONCE() in .proc_handler().
|
||||
* Changing two values seperately could be inconsistent
|
||||
* and some message could be lost. (See: net_ratelimit_state).
|
||||
*/
|
||||
int interval = READ_ONCE(rs->interval);
|
||||
int burst = READ_ONCE(rs->burst);
|
||||
unsigned long flags;
|
||||
int ret;
|
||||
|
||||
if (!rs->interval)
|
||||
if (!interval)
|
||||
return 1;
|
||||
|
||||
/*
|
||||
|
@ -44,7 +50,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
|
|||
if (!rs->begin)
|
||||
rs->begin = jiffies;
|
||||
|
||||
if (time_is_before_jiffies(rs->begin + rs->interval)) {
|
||||
if (time_is_before_jiffies(rs->begin + interval)) {
|
||||
if (rs->missed) {
|
||||
if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE)) {
|
||||
printk_deferred(KERN_WARNING
|
||||
|
@ -56,7 +62,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
|
|||
rs->begin = jiffies;
|
||||
rs->printed = 0;
|
||||
}
|
||||
if (rs->burst && rs->burst > rs->printed) {
|
||||
if (burst && burst > rs->printed) {
|
||||
rs->printed++;
|
||||
ret = 1;
|
||||
} else {
|
||||
|
|
Loading…
Reference in New Issue