Bug 60514 - mac80211/cfg.c: station info not initialized in ieee80211_get_et_stats
Summary: mac80211/cfg.c: station info not initialized in ieee80211_get_et_stats
Status: CLOSED CODE_FIX
Alias: None
Product: Networking
Classification: Unclassified
Component: Wireless (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: networking_wireless@kernel-bugs.osdl.org
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2013-07-05 05:35 UTC by Mikko Rapeli
Modified: 2013-11-13 16:31 UTC (History)
2 users (show)

See Also:
Kernel Version: 3.10 it seems
Tree: Mainline
Regression: No


Attachments

Description Mikko Rapeli 2013-07-05 05:35:16 UTC
Coverity CID 1016544 shows:

579static void ieee80211_get_et_stats(struct wiphy *wiphy,
 580                                   struct net_device *dev,
 581                                   struct ethtool_stats *stats,
 582                                   u64 *data)
 583{
 584        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 585        struct ieee80211_chanctx_conf *chanctx_conf;
 586        struct ieee80211_channel *channel;
 587        struct sta_info *sta;
 588        struct ieee80211_local *local = sdata->local;
    	1. var_decl: Declaring variable "sinfo" without initializer.
 589        struct station_info sinfo;
 590        struct survey_info survey;
 591        int i, q;
 592#define STA_STATS_SURVEY_LEN 7
 593
 594        memset(data, 0, sizeof(u64) * STA_STATS_LEN);
 595
 596#define ADD_STA_STATS(sta)                              \
 597        do {                                            \
 598                data[i++] += sta->rx_packets;           \
 599                data[i++] += sta->rx_bytes;             \
 600                data[i++] += sta->wep_weak_iv_count;    \
 601                data[i++] += sta->num_duplicates;       \
 602                data[i++] += sta->rx_fragments;         \
 603                data[i++] += sta->rx_dropped;           \
 604                                                        \
 605                data[i++] += sinfo.tx_packets;          \
 606                data[i++] += sinfo.tx_bytes;            \
 607                data[i++] += sta->tx_fragments;         \
 608                data[i++] += sta->tx_filtered_count;    \
 609                data[i++] += sta->tx_retry_failed;      \
 610                data[i++] += sta->tx_retry_count;       \
 611                data[i++] += sta->beacon_loss_count;    \
 612        } while (0)
 613
 614        /* For Managed stations, find the single station based on BSSID
 615         * and use that.  For interface types, iterate through all available
 616         * stations and add stats for any station that is assigned to this
 617         * network device.
 618         */
 619
 620        mutex_lock(&local->sta_mtx);
 621
    	2. Condition "sdata->vif.type == NL80211_IFTYPE_STATION", taking false branch
 622        if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 623                sta = sta_info_get_bss(sdata, sdata->u.mgd.bssid);
 624
 625                if (!(sta && !WARN_ON(sta->sdata->dev != dev)))
 626                        goto do_survey;
 627
 628                sinfo.filled = 0;
 629                sta_set_sinfo(sta, &sinfo);
 630
 631                i = 0;
 632                ADD_STA_STATS(sta);
 633
 634                data[i++] = sta->sta_state;
 635
 636
 637                if (sinfo.filled & STATION_INFO_TX_BITRATE)
 638                        data[i] = 100000 *
 639                                cfg80211_calculate_bitrate(&sinfo.txrate);
 640                i++;
 641                if (sinfo.filled & STATION_INFO_RX_BITRATE)
 642                        data[i] = 100000 *
 643                                cfg80211_calculate_bitrate(&sinfo.rxrate);
 644                i++;
 645
 646                if (sinfo.filled & STATION_INFO_SIGNAL_AVG)
 647                        data[i] = (u8)sinfo.signal_avg;
 648                i++;
 649        } else {
    	3. Condition "&sta->list != &local->sta_list", taking true branch
    	6. Condition "&sta->list != &local->sta_list", taking true branch
    	9. Condition "&sta->list != &local->sta_list", taking true branch
 650                list_for_each_entry(sta, &local->sta_list, list) {
 651                        /* Make sure this station belongs to the proper dev */
    	4. Condition "sta->sdata->dev != dev", taking true branch
    	7. Condition "sta->sdata->dev != dev", taking true branch
    	10. Condition "sta->sdata->dev != dev", taking false branch
 652                        if (sta->sdata->dev != dev)
    	5. Continuing loop
    	8. Continuing loop
 653                                continue;
 654
 655                        i = 0;
    	CID 1016544 (2) (#1-2 of 2): Uninitialized scalar variable (UNINIT) [select issue]
    	11. uninit_use: Using uninitialized value "sinfo.tx_packets".
 656                        ADD_STA_STATS(sta);
/net/mac80211/cfg.c
596#define ADD_STA_STATS(sta)                              \
597        do {                                            \
598                data[i++] += sta->rx_packets;           \
599                data[i++] += sta->rx_bytes;             \
600                data[i++] += sta->wep_weak_iv_count;    \
601                data[i++] += sta->num_duplicates;       \
602                data[i++] += sta->rx_fragments;         \
603                data[i++] += sta->rx_dropped;           \
604                                                        \
605                data[i++] += sinfo.tx_packets;          \
606                data[i++] += sinfo.tx_bytes;            \
607                data[i++] += sta->tx_fragments;         \
608                data[i++] += sta->tx_filtered_count;    \
609                data[i++] += sta->tx_retry_failed;      \
610                data[i++] += sta->tx_retry_count;       \
611                data[i++] += sta->beacon_loss_count;    \
612        } while (0)
 657                }
 658        }

Fix could perhaps be just:

--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -592,6 +592,7 @@ static void ieee80211_get_et_stats(struct wiphy *wiphy,
 #define STA_STATS_SURVEY_LEN 7
 
        memset(data, 0, sizeof(u64) * STA_STATS_LEN);
+       memset(&sinfo, 0, sizeof(sinfo));
 
 #define ADD_STA_STATS(sta)                             \
        do {                                            \
Comment 1 Johannes Berg 2013-07-08 08:47:13 UTC
Fixed, thanks.

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