From: Reinette Chatre Date: Wed, 19 Dec 2007 06:01:02 +0000 (-0800) Subject: ipw2200: prevent alloc of unspecified size on stack X-Git-Tag: v2.6.24-rc7~40^2~1^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=412e9e7800360ec93b6ba319b30666f6bfc721bd;p=linux-2.6 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 Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ipw2200.c b/drivers/net/wireless/ipw2200.c index 54f44e5473..38ce8ee8d6 100644 --- a/drivers/net/wireless/ipw2200.c +++ b/drivers/net/wireless/ipw2200.c @@ -1233,9 +1233,19 @@ static ssize_t show_event_log(struct device *d, { 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 @@ static ssize_t show_event_log(struct device *d, "\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; }