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:
struct probe_resp struct fils_discovery_data struct unsol_bcast_probe_resp_data Cc: Johannes Berg <johan...@sipsolutions.net> Cc: "David S. Miller" <da...@davemloft.net> Cc: Eric Dumazet <eduma...@google.com> Cc: Jakub Kicinski <k...@kernel.org> Cc: Paolo Abeni <pab...@redhat.com> Cc: linux-wirel...@vger.kernel.org Cc: net...@vger.kernel.org Signed-off-by: Kees Cook <keesc...@chromium.org> --- net/mac80211/cfg.c | 22 ++++++---------------- net/mac80211/ieee80211_i.h | 12 ++++++------ 2 files changed, 12 insertions(+), 22 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index f1d211e61e49..355edbf41707 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -867,20 +867,16 @@ ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata, const struct ieee80211_csa_settings *csa, const struct ieee80211_color_change_settings *cca) { - struct probe_resp *new, *old; + struct probe_resp *new = NULL, *old; if (!resp || !resp_len) return 1; old = sdata_dereference(sdata->u.ap.probe_resp, sdata); - new = kzalloc(sizeof(struct probe_resp) + resp_len, GFP_KERNEL); - if (!new) + if (mem_to_flex_dup(&new, resp, resp_len, GFP_KERNEL)) return -ENOMEM; - new->len = resp_len; - memcpy(new->data, resp, resp_len); - if (csa) memcpy(new->cntdwn_counter_offsets, csa->counter_offsets_presp, csa->n_counter_offsets_presp * @@ -898,7 +894,7 @@ ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata, static int ieee80211_set_fils_discovery(struct ieee80211_sub_if_data *sdata, struct cfg80211_fils_discovery *params) { - struct fils_discovery_data *new, *old = NULL; + struct fils_discovery_data *new = NULL, *old = NULL; struct ieee80211_fils_discovery *fd; if (!params->tmpl || !params->tmpl_len) @@ -909,11 +905,8 @@ static int ieee80211_set_fils_discovery(struct ieee80211_sub_if_data *sdata, fd->max_interval = params->max_interval; old = sdata_dereference(sdata->u.ap.fils_discovery, sdata); - new = kzalloc(sizeof(*new) + params->tmpl_len, GFP_KERNEL); - if (!new) + if (mem_to_flex_dup(&new, params->tmpl, params->tmpl_len, GFP_KERNEL)) return -ENOMEM; - new->len = params->tmpl_len; - memcpy(new->data, params->tmpl, params->tmpl_len); rcu_assign_pointer(sdata->u.ap.fils_discovery, new); if (old) @@ -926,17 +919,14 @@ static int ieee80211_set_unsol_bcast_probe_resp(struct ieee80211_sub_if_data *sdata, struct cfg80211_unsol_bcast_probe_resp *params) { - struct unsol_bcast_probe_resp_data *new, *old = NULL; + struct unsol_bcast_probe_resp_data *new = NULL, *old = NULL; if (!params->tmpl || !params->tmpl_len) return -EINVAL; old = sdata_dereference(sdata->u.ap.unsol_bcast_probe_resp, sdata); - new = kzalloc(sizeof(*new) + params->tmpl_len, GFP_KERNEL); - if (!new) + if (mem_to_flex_dup(&new, params->tmpl, params->tmpl_len, GFP_KERNEL)) return -ENOMEM; - new->len = params->tmpl_len; - memcpy(new->data, params->tmpl, params->tmpl_len); rcu_assign_pointer(sdata->u.ap.unsol_bcast_probe_resp, new); if (old) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index d4a7ba4a8202..2e9bbfb12c0d 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -263,21 +263,21 @@ struct beacon_data { struct probe_resp { struct rcu_head rcu_head; - int len; + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(int, len); u16 cntdwn_counter_offsets[IEEE80211_MAX_CNTDWN_COUNTERS_NUM]; - u8 data[]; + DECLARE_FLEX_ARRAY_ELEMENTS(u8, data); }; struct fils_discovery_data { struct rcu_head rcu_head; - int len; - u8 data[]; + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(int, len); + DECLARE_FLEX_ARRAY_ELEMENTS(u8, data); }; struct unsol_bcast_probe_resp_data { struct rcu_head rcu_head; - int len; - u8 data[]; + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(int, len); + DECLARE_FLEX_ARRAY_ELEMENTS(u8, data); }; struct ps_data { -- 2.32.0