diff options
| author | Amitkumar Karwar <akarwar@marvell.com> | 2013-10-22 15:24:45 -0700 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2013-11-11 14:38:57 -0500 |
| commit | 2636c308fd720137d719c91da95adca2cd8f1c51 (patch) | |
| tree | bf60abf98eb45eb883656e2add8bee7acd989dfc | |
| parent | fe1c9a443e0d1e0af790883f091fb1c4f418bc8f (diff) | |
mwifiex: fix invalid memory access in mwifiex_ret_tx_rate_cfg()
As tlv_buf_len is decremented at the end of the loop, we may have
accessed invalid memory in the last iteration.
Modify the while condition and add a break statement at the
begining of the loop to fix the problem.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | drivers/net/wireless/mwifiex/sta_cmdresp.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/drivers/net/wireless/mwifiex/sta_cmdresp.c b/drivers/net/wireless/mwifiex/sta_cmdresp.c index 5edea4dd05a..2675ca7f8d1 100644 --- a/drivers/net/wireless/mwifiex/sta_cmdresp.c +++ b/drivers/net/wireless/mwifiex/sta_cmdresp.c @@ -274,17 +274,20 @@ static int mwifiex_ret_tx_rate_cfg(struct mwifiex_private *priv, struct host_cmd_ds_tx_rate_cfg *rate_cfg = &resp->params.tx_rate_cfg; struct mwifiex_rate_scope *rate_scope; struct mwifiex_ie_types_header *head; - u16 tlv, tlv_buf_len; + u16 tlv, tlv_buf_len, tlv_buf_left; u8 *tlv_buf; u32 i; - tlv_buf = ((u8 *)rate_cfg) + - sizeof(struct host_cmd_ds_tx_rate_cfg); - tlv_buf_len = le16_to_cpu(*(__le16 *) (tlv_buf + sizeof(u16))); + tlv_buf = ((u8 *)rate_cfg) + sizeof(struct host_cmd_ds_tx_rate_cfg); + tlv_buf_left = le16_to_cpu(resp->size) - S_DS_GEN - sizeof(*rate_cfg); - while (tlv_buf && tlv_buf_len > 0) { - tlv = (*tlv_buf); - tlv = tlv | (*(tlv_buf + 1) << 8); + while (tlv_buf_left >= sizeof(*head)) { + head = (struct mwifiex_ie_types_header *)tlv_buf; + tlv = le16_to_cpu(head->type); + tlv_buf_len = le16_to_cpu(head->len); + + if (tlv_buf_left < (sizeof(*head) + tlv_buf_len)) + break; switch (tlv) { case TLV_TYPE_RATE_SCOPE: @@ -304,9 +307,8 @@ static int mwifiex_ret_tx_rate_cfg(struct mwifiex_private *priv, /* Add RATE_DROP tlv here */ } - head = (struct mwifiex_ie_types_header *) tlv_buf; - tlv_buf += le16_to_cpu(head->len) + sizeof(*head); - tlv_buf_len -= le16_to_cpu(head->len); + tlv_buf += (sizeof(*head) + tlv_buf_len); + tlv_buf_left -= (sizeof(*head) + tlv_buf_len); } priv->is_data_rate_auto = mwifiex_is_rate_auto(priv); |