diff options
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/fs/namei.c b/fs/namei.c index 89a612e392eb..7720fbd5277b 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -536,8 +536,8 @@ static int unlazy_walk(struct nameidata *nd, struct dentry *dentry) * a reference at this point. */ BUG_ON(!IS_ROOT(dentry) && dentry->d_parent != parent); - BUG_ON(!parent->d_count); - parent->d_count++; + BUG_ON(!parent->d_lockref.count); + parent->d_lockref.count++; spin_unlock(&dentry->d_lock); } spin_unlock(&parent->d_lock); @@ -3327,7 +3327,7 @@ void dentry_unhash(struct dentry *dentry) { shrink_dcache_parent(dentry); spin_lock(&dentry->d_lock); - if (dentry->d_count == 1) + if (dentry->d_lockref.count == 1) __d_drop(dentry); spin_unlock(&dentry->d_lock); } @@ -3671,11 +3671,15 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) return -EINVAL; /* - * Using empty names is equivalent to using AT_SYMLINK_FOLLOW - * on /proc/self/fd/<fd>. + * To use null names we require CAP_DAC_READ_SEARCH + * This ensures that not everyone will be able to create + * handlink using the passed filedescriptor. */ - if (flags & AT_EMPTY_PATH) + if (flags & AT_EMPTY_PATH) { + if (!capable(CAP_DAC_READ_SEARCH)) + return -ENOENT; how = LOOKUP_EMPTY; + } if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; |