As part of the work to perform bounds checking on all memcpy() uses, replace the open-coded a deserialization of bytes out of memory into a trailing flexible array by using a flex_array.h helper to perform the allocation, bounds checking, and copying.
Cc: Johannes Berg <johan...@sipsolutions.net> Cc: "David S. Miller" <da...@davemloft.net> Cc: Jakub Kicinski <k...@kernel.org> Cc: Paolo Abeni <pab...@redhat.com> Cc: linux-wirel...@vger.kernel.org Cc: net...@vger.kernel.org Cc: Eric Dumazet <eduma...@google.com> Signed-off-by: Kees Cook <keesc...@chromium.org> --- net/wireless/core.h | 4 ++-- net/wireless/nl80211.c | 15 ++++----------- 2 files changed, 6 insertions(+), 13 deletions(-) diff --git a/net/wireless/core.h b/net/wireless/core.h index 3a7dbd63d8c6..899d111993c6 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -295,8 +295,8 @@ struct cfg80211_beacon_registration { struct cfg80211_cqm_config { u32 rssi_hyst; s32 last_rssi_event_value; - int n_rssi_thresholds; - s32 rssi_thresholds[]; + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(int, n_rssi_thresholds); + DECLARE_FLEX_ARRAY_ELEMENTS(s32, rssi_thresholds); }; void cfg80211_destroy_ifaces(struct cfg80211_registered_device *rdev); diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 945ed87d12e0..70df7132cce8 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -12096,21 +12096,14 @@ static int nl80211_set_cqm_rssi(struct genl_info *info, wdev_lock(wdev); if (n_thresholds) { - struct cfg80211_cqm_config *cqm_config; + struct cfg80211_cqm_config *cqm_config = NULL; - cqm_config = kzalloc(struct_size(cqm_config, rssi_thresholds, - n_thresholds), - GFP_KERNEL); - if (!cqm_config) { - err = -ENOMEM; + err = mem_to_flex_dup(&cqm_config, thresholds, n_thresholds, + GFP_KERNEL); + if (err) goto unlock; - } cqm_config->rssi_hyst = hysteresis; - cqm_config->n_rssi_thresholds = n_thresholds; - memcpy(cqm_config->rssi_thresholds, thresholds, - flex_array_size(cqm_config, rssi_thresholds, - n_thresholds)); wdev->cqm_config = cqm_config; } -- 2.32.0