Patch "proc: fix -ESRCH error when writing to /proc/$pid/coredump_filter" has been added to the 4.3-stable tree

This is a note to let you know that I've just added the patch titled

proc: fix -ESRCH error when writing to /proc/$pid/coredump_filter

to the 4.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
proc-fix-esrch-error-when-writing-to-proc-pid-coredump_filter.patch
and it can be found in the queue-4.3 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Colin Ian King <[email protected]>
Date: Fri, 18 Dec 2015 14:22:01 -0800
Subject: proc: fix -ESRCH error when writing to /proc/$pid/coredump_filter

From: Colin Ian King <[email protected]>

commit 41a0c249cb8706a2efa1ab3d59466b23a27d0c8b upstream.

Writing to /proc/$pid/coredump_filter always returns -ESRCH because commit 774636e19ed51 ("proc: convert to kstrto*()/kstrto*_from_user()") removed the setting of ret after the get_proc_task call and incorrectly left it as -ESRCH. Instead, return 0 when successful.

Example breakage:

echo 0 > /proc/self/coredump_filter
bash: echo: write error: No such process

---
 fs/proc/base.c |    1 +
 1 file changed, 1 insertion(+)

@@ -2484,6 +2484,7 @@ static ssize_t proc_coredump_filter_writ
 	mm = get_task_mm(task);
 	if (!mm)
 		goto out_no_mm;
+	ret = 0;
 
 	for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
 		if (val & mask)

Patches currently in stable-queue which might be from [email protected] are

queue-4.3/proc-fix-esrch-error-when-writing-to-proc-pid-coredump_filter.patch