Commit edef3098 authored by Wolfram Sang's avatar Wolfram Sang
Browse files

Merge tag 'at24-4.15-fixes-for-wolfram' of... 

Merge tag 'at24-4.15-fixes-for-wolfram' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into i2c/for-current

Please consider pulling the following fixes for v4.15. While it doesn't
fix any regression introduced in the v4.15 merge window, we have a
feature in at24 since linux v4.8 - reading the mac address block from
at24mac series - which turned out to be not working.

This pull request contains changes that fix it together with a patch
that hardens the read and write argument sanitization with
out-of-bounds checks that were missing.
parents 66a7c84d d9bcd462

drivers/misc/eeprom/at24.c

+18 −1
Original line number Diff line number Diff line
@@ -425,7 +425,8 @@ static ssize_t at24_eeprom_read_mac(struct at24_data *at24, char *buf, 
	memset(msg, 0, sizeof(msg));

	msg[0].addr = client->addr;

	msg[0].buf = addrbuf;

	addrbuf[0] = 0x90 + offset;

	/* EUI-48 starts from 0x9a, EUI-64 from 0x98 */

	addrbuf[0] = 0xa0 - at24->chip.byte_len + offset;

	msg[0].len = 1;

	msg[1].addr = client->addr;

	msg[1].flags = I2C_M_RD;
@@ -568,6 +569,9 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count) 
	if (unlikely(!count))

		return count;



	if (off + count > at24->chip.byte_len)

		return -EINVAL;



	client = at24_translate_offset(at24, &off);



	ret = pm_runtime_get_sync(&client->dev);
@@ -613,6 +617,9 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) 
	if (unlikely(!count))

		return -EINVAL;



	if (off + count > at24->chip.byte_len)

		return -EINVAL;



	client = at24_translate_offset(at24, &off);



	ret = pm_runtime_get_sync(&client->dev);
@@ -730,6 +737,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) 
		dev_warn(&client->dev,

			"page_size looks suspicious (no power of 2)!\n");



	/*

	 * REVISIT: the size of the EUI-48 byte array is 6 in at24mac402, while

	 * the call to ilog2() in AT24_DEVICE_MAGIC() rounds it down to 4.

	 *

	 * Eventually we'll get rid of the magic values altoghether in favor of

	 * real structs, but for now just manually set the right size.

	 */

	if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4)

		chip.byte_len = 6;



	/* Use I2C operations unless we're stuck with SMBus extensions. */

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {

		if (chip.flags & AT24_FLAG_ADDR16)

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