[PATCH AUTOSEL 5.13 13/19] connector: send event on write to /proc/[pid]/comm

Sasha Levin
2021-09-13T22:36:28Z

From: Ohhoon Kwon <ohoono.kwon@samsung.com>

[ Upstream commit c2f273ebd89a79ed87ef1025753343e327b99ac9 ]

While comm change event via prctl has been reported to proc connector by
'commit f786ecba4158 ("connector: add comm change event report to proc
connector")', connector listeners were missing comm changes by explicit
writes on /proc/[pid]/comm.

Let explicit writes on /proc/[pid]/comm report to proc connector.

Link: https://lkml.kernel.org/r/20210701133458epcms1p68e9eb9bd0eee8903ba26679a37d9d960@epcms1p6
Signed-off-by: Ohhoon Kwon <ohoono.kwon@samsung.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/proc/base.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index a0a2fc1c9da2..641389868deb 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -95,6 +95,7 @@
#include <linux/posix-timers.h>
#include <linux/time_namespace.h>
#include <linux/resctrl.h>
+#include <linux/cn_proc.h>
#include <trace/events/oom.h>
#include "internal.h"
#include "fd.h"
@@ -1674,8 +1675,10 @@ static ssize_t comm_write(struct file *file, const char __user *buf,
if (!p)
return -ESRCH;

- if (same_thread_group(current, p))
+ if (same_thread_group(current, p)) {
set_task_comm(p, buffer);
+ proc_comm_connector(p);
+ }
else
count = -EINVAL;

--
2.30.2