From 307ac652e9fb6f7757a5018e43b64bf05c9ac544 Mon Sep 17 00:00:00 2001 From: Zhou Qingyang Date: Mon, 13 Dec 2021 11:53:07 +0200 Subject: [PATCH] ath11k: Fix a NULL pointer dereference in ath11k_mac_op_hw_scan() [ Upstream commit eccd25136386a04ebf46a64f3a34e8e0fab6d9e1 ] In ath11k_mac_op_hw_scan(), the return value of kzalloc() is directly used in memcpy(), which may lead to a NULL pointer dereference on failure of kzalloc(). Fix this bug by adding a check of arg.extraie.ptr. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_ATH11K=m show no new warnings, and our static analyzer no longer warns about this code. Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Signed-off-by: Zhou Qingyang Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20211202155348.71315-1-zhou1615@umn.edu Signed-off-by: Sasha Levin --- drivers/net/wireless/ath/ath11k/mac.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c index 9dfa77389c4d..f8f973ef150e 100644 --- a/drivers/net/wireless/ath/ath11k/mac.c +++ b/drivers/net/wireless/ath/ath11k/mac.c @@ -2580,9 +2580,12 @@ static int ath11k_mac_op_hw_scan(struct ieee80211_hw *hw, arg.scan_id = ATH11K_SCAN_ID; if (req->ie_len) { + arg.extraie.ptr = kmemdup(req->ie, req->ie_len, GFP_KERNEL); + if (!arg.extraie.ptr) { + ret = -ENOMEM; + goto exit; + } arg.extraie.len = req->ie_len; - arg.extraie.ptr = kzalloc(req->ie_len, GFP_KERNEL); - memcpy(arg.extraie.ptr, req->ie, req->ie_len); } if (req->n_ssids) {