In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drop_monitor: fix out-of-bounds write in reset_per_cpu_data()<\/p>\n
In reset_per_cpu_data(), al is computed as:<\/p>\n
al = sizeof(struct net_dm_alert_msg);
\n al += dm_hit_limit * sizeof(struct net_dm_drop_point);
\n al += sizeof(struct nlattr);<\/p>\n
skb = genlmsg_new(al, GFP_KERNEL);
\n …
\n nla = nla_reserve(skb, NLA_UNSPEC, sizeof(struct net_dm_alert_msg));
\n …
\n msg = nla_data(nla);
\n memset(msg, 0, al);<\/p>\n
Because al includes sizeof(struct nlattr) (the 4-byte attribute header),
\ngenlmsg_new() allocates al bytes of tailroom starting at nla.
\nHowever, msg points to nla_data(nla), which is located
\nsizeof(struct nlattr) bytes past nla. Calling memset(msg, 0, al)
\ntherefore writes al bytes starting from msg, exceeding the allocated
\nbuffer by sizeof(struct nlattr) (4 bytes) and corrupting
\nskb_shared_info.<\/p>\n
Fix this by letting al represent only the payload length, allocating
\nthe skb with genlmsg_new(nla_total_size(al), GFP_KERNEL), and zeroing
\nal bytes from msg.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drop_monitor: fix out-of-bounds write in reset_per_cpu_data()<\/p>\n
In reset_per_cpu_data(), al is computed as:<\/p>\n
al = sizeof(struct <\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-39090","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/39090","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=39090"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=39090"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=39090"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}