Commit 71d46f1f authored by Dan Carpenter's avatar Dan Carpenter Committed by Greg Kroah-Hartman
Browse files

eeprom: idt_89hpesx: uninitialized data in idt_dbgfs_csr_write() 



The simple_write_to_buffer() function will return positive/success if it
is able to write a single byte anywhere within the buffer.  However that
potentially leaves a lot of the buffer uninitialized.

In this code it's better to return 0 if the offset is non-zero.  This
code is not written to support partial writes.  And then return -EFAULT
if the buffer is not completely initialized.

Fixes: cfad6425 ("eeprom: Add IDT 89HPESx EEPROM/CSR driver")
Reviewed-by: default avatarSerge Semin <fancer.lancer@gmail.com>
Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/Ysg1Pu/nzSMe3r1q@kili


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2a3c8f8a

drivers/misc/eeprom/idt_89hpesx.c

+6 −2
Original line number Diff line number Diff line
@@ -909,14 +909,18 @@ static ssize_t idt_dbgfs_csr_write(struct file *filep, const char __user *ubuf, 
	u32 csraddr, csrval;

	char *buf;



	if (*offp)

		return 0;



	/* Copy data from User-space */

	buf = kmalloc(count + 1, GFP_KERNEL);

	if (!buf)

		return -ENOMEM;



	ret = simple_write_to_buffer(buf, count, offp, ubuf, count);

	if (ret < 0)

	if (copy_from_user(buf, ubuf, count)) {

		ret = -EFAULT;

		goto free_buf;

	}

	buf[count] = 0;



	/* Find position of colon in the buffer */