diff options
Diffstat (limited to 'security/security.c')
| -rw-r--r-- | security/security.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/security/security.c b/security/security.c index 5b2e0a15377d..7e118858b545 100644 --- a/security/security.c +++ b/security/security.c @@ -780,7 +780,9 @@ static int lsm_superblock_alloc(struct super_block *sb) * @id: LSM id * @flags: LSM defined flags * - * Fill all of the fields in a userspace lsm_ctx structure. + * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL + * simply calculate the required size to output via @utc_len and return + * success. * * Returns 0 on success, -E2BIG if userspace buffer is not large enough, * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. @@ -799,6 +801,10 @@ int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, goto out; } + /* no buffer - return success/0 and set @uctx_len to the req size */ + if (!uctx) + goto out; + nctx = kzalloc(nctx_len, GFP_KERNEL); if (nctx == NULL) { rc = -ENOMEM; |