openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 

Pull key handling bugfix from James Morris:
 "Fix a race between keyctl_read() and keyctl_revoke()"

* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  KEYS: Fix race between read and revoke
This commit is contained in:
Linus Torvalds 2015-12-28 10:35:19 -08:00
parent 74bf8efb5f b4a1b4f504
commit 2c7143d4f5
1 changed files with 9 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
security/keys/keyctl.c
View File

@ -751,17 +751,17 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
/* the key is probably readable - now try to read it */ /* the key is probably readable - now try to read it */
can_read_key: can_read_key:
ret = key_validate(key);
if (ret == 0) {
ret = -EOPNOTSUPP; ret = -EOPNOTSUPP;
if (key->type->read) { if (key->type->read) {
/* read the data with the semaphore held (since we /* Read the data with the semaphore held (since we might sleep)
* might sleep) */ * to protect against the key being updated or revoked.
*/
down_read(&key->sem); down_read(&key->sem);
ret = key_validate(key);
if (ret == 0)
ret = key->type->read(key, buffer, buflen); ret = key->type->read(key, buffer, buflen);
up_read(&key->sem); up_read(&key->sem);
} }
}
error2: error2:
key_put(key); key_put(key);