In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net: xps: reject an out of range traffic class<\/p>\n
Only the entries below dev->num_tc are valid in dev->tc_to_txq[], and
\ndev->prio_tc_map[] may only name classes below it. netdev_set_num_tc()
\nlowers dev->num_tc without touching either array.<\/p>\n
netdev_txq_to_tc() walks all TC_MAX_QUEUE slots and
\nnetdev_get_prio_tc_map() returns the entry as it stands, so a leftover
\nentry is handed out as a traffic class >= dev->num_tc. Taking that
\nclass from netdev_txq_to_tc(), __netif_set_xps_queue() rejects only a
\nnegative one and indexes an XPS map sized for dev->num_tc classes:<\/p>\n
\ttci = j * num_tc + tc;
\n\tRCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);<\/p>\n
attr_map[] holds nr_ids * num_tc entries and j runs over the ids named
\nin the mask, so a class that is not below num_tc pushes tci past the end
\nof the map for the last ids and the store overruns it.<\/p>\n
Any caller that lowers num_tc leaves such entries behind, and
\nmqprio_destroy() tears down with netdev_set_num_tc(dev, 0) rather than
\nnetdev_reset_tc(). After mqprio with 8 classes then 1, tc_to_txq[1..7]
\nstill describe txq 1..7. The splat is from an XPS write to txq 2 on a
\nveth with 8 rx queues: attr_map[] has 8 * 1 entries, tci = j + 2, and
\nj == 6 stores one past the end of the 88-byte map:<\/p>\n
BUG: KASAN: slab-out-of-bounds in __netif_set_xps_queue (net\/core\/dev.c:2954)
\n Write of size 8 at addr ffff88813016bc58 by task xps_oob\/634
\n __netif_set_xps_queue (net\/core\/dev.c:2954)
\n xps_rxqs_store (net\/core\/net-sysfs.c:1880)
\n netdev_queue_attr_store (net\/core\/net-sysfs.c:1390)
\n Allocated by task 634:
\n __kmalloc_noprof (mm\/slub.c:5439)
\n __netif_set_xps_queue (net\/core\/dev.c:2937)
\n The buggy address is located 0 bytes to the right of
\n allocated 88-byte region [ffff88813016bc00, ffff88813016bc58)<\/p>\n
Reject a class the map has no room for.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
net: xps: reject an out of range traffic class<\/p>\n
Only the entries below dev->num_tc are valid in dev->tc_to_txq[], and
\ndev->prio_tc_<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-41039","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/41039","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=41039"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=41039"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=41039"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}