diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2014-01-17 17:29:36 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-01-17 17:29:36 -0800
commit48ba620aab90f4c7e9bb002e2f30863a4ea0f915 (patch)
parent8f211b6ccc01d058fc6c6466c7815f2315130b2e (diff)
parent41301ae78a99ead04ea42672a1ab72c6f44cc81d (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull namespace fixes from Eric Biederman: "This is a set of 3 regression fixes. This fixes /proc/mounts when using "ip netns add <netns>" to display the actual mount point. This fixes a regression in clone that broke lxc-attach. This fixes a regression in the permission checks for mounting /proc that made proc unmountable if binfmt_misc was in use. Oops. My apologies for sending this pull request so late. Al Viro gave interesting review comments about the d_path fix that I wanted to address in detail before I sent this pull request. Unfortunately a bad round of colds kept from addressing that in detail until today. The executive summary of the review was: Al: Is patching d_path really sufficient? The prepend_path, d_path, d_absolute_path, and __d_path family of functions is a really mess. Me: Yes, patching d_path is really sufficient. Yes, the code is mess. No it is not appropriate to rewrite all of d_path for a regression that has existed for entirely too long already, when a two line change will do" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: vfs: Fix a regression in mounting proc fork: Allow CLONE_PARENT after setns(CLONE_NEWPID) vfs: In d_path don't call d_dname on a mount point
3 files changed, 8 insertions, 3 deletions
diff --git a/fs/dcache.c b/fs/dcache.c
index 6055d61811d..cb4a1069086 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -3061,8 +3061,13 @@ char *d_path(const struct path *path, char *buf, int buflen)
* thus don't need to be hashed. They also don't need a name until a
* user wants to identify the object in /proc/pid/fd/. The little hack
* below allows us to generate a name for these objects on demand:
+ *
+ * Some pseudo inodes are mountable. When they are mounted
+ * path->dentry == path->mnt->mnt_root. In that case don't call d_dname
+ * and instead have d_path return the mounted path.
- if (path->dentry->d_op && path->dentry->d_op->d_dname)
+ if (path->dentry->d_op && path->dentry->d_op->d_dname &&
+ (!IS_ROOT(path->dentry) || path->dentry != path->mnt->mnt_root))
return path->dentry->d_op->d_dname(path->dentry, buf, buflen);
diff --git a/fs/namespace.c b/fs/namespace.c
index ac2ce8a766e..be32ebccdeb 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2886,7 +2886,7 @@ bool fs_fully_visible(struct file_system_type *type)
struct inode *inode = child->mnt_mountpoint->d_inode;
if (!S_ISDIR(inode->i_mode))
goto next;
- if (inode->i_nlink != 2)
+ if (inode->i_nlink > 2)
goto next;
visible = true;
diff --git a/kernel/fork.c b/kernel/fork.c
index 5721f0e3f2d..dfa736c98d1 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1172,7 +1172,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
* do not allow it to share a thread group or signal handlers or
* parent with the forking task.
- if (clone_flags & (CLONE_SIGHAND | CLONE_PARENT)) {
+ if (clone_flags & CLONE_SIGHAND) {
if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) ||
(task_active_pid_ns(current) !=