Patch "mwifiex: fix mwifiex_rdeeprom_read()" has been added to the 3.14-stable tree

Patch "mwifiex: fix mwifiex_rdeeprom_read()" has been added to the 3.14-stable tree

[gregkh]

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

    mwifiex: fix mwifiex_rdeeprom_read()

to the 3.14-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:
     mwifiex-fix-mwifiex_rdeeprom_read.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 1f9c6e1bc1ba5f8a10fcd6e99d170954d7c6d382 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 21 Sep 2015 19:19:53 +0300
Subject: mwifiex: fix mwifiex_rdeeprom_read()

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 1f9c6e1bc1ba5f8a10fcd6e99d170954d7c6d382 upstream.

There were several bugs here.

1)  The done label was in the wrong place so we didn't copy any
    information out when there was no command given.

2)  We were using PAGE_SIZE as the size of the buffer instead of
    "PAGE_SIZE - pos".

3)  snprintf() returns the number of characters that would have been
    printed if there were enough space.  If there was not enough space
    (and we had fixed the memory corruption bug #2) then it would result
    in an information leak when we do simple_read_from_buffer().  I've
    changed it to use scnprintf() instead.

I also removed the initialization at the start of the function, because
I thought it made the code a little more clear.

Fixes: 5e6e3a92b9a4 ('wireless: mwifiex: initial commit for Marvell mwifiex driver')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/wireless/mwifiex/debugfs.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/drivers/net/wireless/mwifiex/debugfs.c
+++ b/drivers/net/wireless/mwifiex/debugfs.c
@@ -637,7 +637,7 @@ mwifiex_rdeeprom_read(struct file *file,
 		(struct mwifiex_private *) file->private_data;
 	unsigned long addr = get_zeroed_page(GFP_KERNEL);
 	char *buf = (char *) addr;
-	int pos = 0, ret = 0, i;
+	int pos, ret, i;
 	u8 value[MAX_EEPROM_DATA];
 
 	if (!buf)
@@ -645,7 +645,7 @@ mwifiex_rdeeprom_read(struct file *file,
 
 	if (saved_offset == -1) {
 		/* No command has been given */
-		pos += snprintf(buf, PAGE_SIZE, "0");
+		pos = snprintf(buf, PAGE_SIZE, "0");
 		goto done;
 	}
 
@@ -654,17 +654,17 @@ mwifiex_rdeeprom_read(struct file *file,
 				  (u16) saved_bytes, value);
 	if (ret) {
 		ret = -EINVAL;
-		goto done;
+		goto out_free;
 	}
 
-	pos += snprintf(buf, PAGE_SIZE, "%d %d ", saved_offset, saved_bytes);
+	pos = snprintf(buf, PAGE_SIZE, "%d %d ", saved_offset, saved_bytes);
 
 	for (i = 0; i < saved_bytes; i++)
-		pos += snprintf(buf + strlen(buf), PAGE_SIZE, "%d ", value[i]);
-
-	ret = simple_read_from_buffer(ubuf, count, ppos, buf, pos);
+		pos += scnprintf(buf + pos, PAGE_SIZE - pos, "%d ", value[i]);
 
 done:
+	ret = simple_read_from_buffer(ubuf, count, ppos, buf, pos);
+out_free:
 	free_page(addr);
 	return ret;
 }


Patches currently in stable-queue which might be from dan.carpenter@oracle.com are

queue-3.14/irda-precedence-bug-in-irlmp_seq_hb_idx.patch
queue-3.14/mwifiex-fix-mwifiex_rdeeprom_read.patch