wlan: Fix buffer overwrite problem in GETBAND
If (len + 1) is greater than priv_data.total_len then copy_to_user
results in writing more data than the buffer can hold.
Fix this by writing mininum of (len + 1) and priv_data.total_len.
CRs-Fixed: 865589
Change-Id: I134d21c1c73d4b1287aef7f78a59d18539c9d3dc
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index 5258e06..2c165a9 100755
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -2748,8 +2748,8 @@
TRACE_CODE_HDD_GETBAND_IOCTL,
pAdapter->sessionId, band));
len = scnprintf(extra, sizeof(extra), "%s %d", command, band);
- if (copy_to_user(priv_data.buf, &extra, len + 1))
- {
+ len = VOS_MIN(priv_data.total_len, len + 1);
+ if (copy_to_user(priv_data.buf, &extra, len)) {
VOS_TRACE( VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
"%s: failed to copy data to user buffer", __func__);
ret = -EFAULT;