[merged] proc-dont-show-nonexistent-capabilities.patch removed from -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: proc: don't show nonexistent capabilities
has been removed from the -mm tree.  Its filename was
     proc-dont-show-nonexistent-capabilities.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Andrew Vagin <avagin@openvz.org>
Subject: proc: don't show nonexistent capabilities

Without this patch it is really hard to interpret a bounding set, if
CAP_LAST_CAP is unknown for a current kernel.

Non-existant capabilities can not be deleted from a bounding set with help
of prctl.

E.g.: Here are two examples without/with this patch.
CapBnd:	ffffffe0fdecffff
CapBnd:	00000000fdecffff

I suggest to hide non-existent capabilities. Here is two reasons.
* It's logically and easier for using.
* It helps to checkpoint-restore capabilities of tasks, because tasks
can be restored on another kernel, where CAP_LAST_CAP is bigger.

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Cc: Andrew G. Morgan <morgan@kernel.org>
Reviewed-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/array.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff -puN fs/proc/array.c~proc-dont-show-nonexistent-capabilities fs/proc/array.c
--- a/fs/proc/array.c~proc-dont-show-nonexistent-capabilities
+++ a/fs/proc/array.c
@@ -308,6 +308,10 @@ static void render_cap_t(struct seq_file
 	seq_putc(m, '\n');
 }
 
+/* Remove non-existent capabilities */
+#define NORM_CAPS(v) (v.cap[CAP_TO_INDEX(CAP_LAST_CAP)] &= \
+				CAP_TO_MASK(CAP_LAST_CAP + 1) - 1)
+
 static inline void task_cap(struct seq_file *m, struct task_struct *p)
 {
 	const struct cred *cred;
@@ -321,6 +325,11 @@ static inline void task_cap(struct seq_f
 	cap_bset	= cred->cap_bset;
 	rcu_read_unlock();
 
+	NORM_CAPS(cap_inheritable);
+	NORM_CAPS(cap_permitted);
+	NORM_CAPS(cap_effective);
+	NORM_CAPS(cap_bset);
+
 	render_cap_t(m, "CapInh:\t", &cap_inheritable);
 	render_cap_t(m, "CapPrm:\t", &cap_permitted);
 	render_cap_t(m, "CapEff:\t", &cap_effective);
_

Patches currently in -mm which might be from avagin@openvz.org are

origin.patch
fs-notify-add-procfs-fdinfo-helper-v7-fix.patch