@@ -660,7 +660,7 @@ mwifiex_rdeeprom_read(struct file *file, char __user *ubuf,
(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)
@@ -668,7 +668,7 @@ mwifiex_rdeeprom_read(struct file *file, char __user *ubuf,
if (saved_offset == -1) {
/* No command has been given */
- pos += snprintf(buf, PAGE_SIZE, "0");
+ pos = snprintf(buf, PAGE_SIZE, "0");
goto done;
}
@@ -677,17 +677,17 @@ mwifiex_rdeeprom_read(struct file *file, char __user *ubuf,
(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;
}
This is a note to let you know that I have just added a patch titled mwifiex: fix mwifiex_rdeeprom_read() to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt21. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 1c47fa1b074af20a51b998a9065cf8f5d9264c46 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() 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: Luis Henriques <luis.henriques@canonical.com> --- drivers/net/wireless/mwifiex/debugfs.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)