ipw2200: prevent alloc of unspecified size on stack
if log_len is larger than 4K then we are killing the stack.
allocate on heap instead and limit size to what practically can
be used (PAGE_SIZE)
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ipw2200.c b/drivers/net/wireless/ipw2200.c
index 54f44e5..38ce8ee 100644
--- a/drivers/net/wireless/ipw2200.c
+++ b/drivers/net/wireless/ipw2200.c
@@ -1233,9 +1233,19 @@
{
struct ipw_priv *priv = dev_get_drvdata(d);
u32 log_len = ipw_get_event_log_len(priv);
- struct ipw_event log[log_len];
+ u32 log_size;
+ struct ipw_event *log;
u32 len = 0, i;
+ /* not using min() because of its strict type checking */
+ log_size = PAGE_SIZE / sizeof(*log) > log_len ?
+ sizeof(*log) * log_len : PAGE_SIZE;
+ log = kzalloc(log_size, GFP_KERNEL);
+ if (!log) {
+ IPW_ERROR("Unable to allocate memory for log\n");
+ return 0;
+ }
+ log_len = log_size / sizeof(*log);
ipw_capture_event_log(priv, log_len, log);
len += snprintf(buf + len, PAGE_SIZE - len, "%08X", log_len);
@@ -1244,6 +1254,7 @@
"\n%08X%08X%08X",
log[i].time, log[i].event, log[i].data);
len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+ kfree(log);
return len;
}