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authorWolfram Sang <wsa@the-dreams.de>2017-12-02 23:32:13 +0100
committerWolfram Sang <wsa@the-dreams.de>2017-12-03 15:55:20 +0100
commitedef30980dc06bea547baefcfc8d910682b6e060 (patch)
tree2edc620174584101b8cda42f078bce9d0103204e /drivers/misc/eeprom/at24.c
parent66a7c84d677e8e4a5a2ef4afdb9bd52e1399a866 (diff)
parentd9bcd462daf34aebb8de9ad7f76de0198bb5a0f0 (diff)
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.
Diffstat (limited to 'drivers/misc/eeprom/at24.c')
-rw-r--r--drivers/misc/eeprom/at24.c19
1 files changed, 18 insertions, 1 deletions
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index e0b4b36ef010..305a7a464d09 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -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)