In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
inet: frags: invalidate queues before flushing them<\/p>\n
fqdir_pre_exit() flushes the skbs from incomplete queues without
\nchanging their completion state. A fragment which found a queue before
\nhigh_thresh was cleared can then acquire the queue lock and reuse stale
\nreassembly metadata. A queue concurrently killed after fqdir->dead is
\nset can instead become INET_FRAG_COMPLETE|INET_FRAG_HASH_DEAD while
\nstill holding its old skbs; skipping it because it is complete leaves
\nthose references behind until asynchronous fqdir teardown.<\/p>\n
For IPv6, stale metadata can make ip6_frag_reasm() use the old
\nnhoffset with a new skb and access memory out of bounds. The resulting
\nheap corruption can be leveraged for local privilege escalation when
\nunprivileged network namespaces are available. Unflushed fragments can
\nalso keep conntrack references alive after the conntrack per-net
\ncleanup point.<\/p>\n
Kill each incomplete queue, then flush every queue still owned by the
\ndying rhashtable. HASH_DEAD identifies that ownership, while complete
\nqueues without it are already owned by another destroy path and must be
\nleft alone. Releasing a timer reference removed by inet_frag_kill() is
\ndeferred to inet_frag_putn(), after the queue lock is dropped.<\/p>\n
KASAN report:<\/p>\n
BUG: KASAN: slab-out-of-bounds in ipv6_frag_rcv (net\/ipv6\/reassembly.c:289 (discriminator 2) net\/ipv6\/reassembly.c:229 (discriminator 2) net\/ipv6\/reassembly.c:391 (discriminator 2))
\n Write of size 1 at addr ff110001039c6e00 by task poc\/771
\n Call Trace:
\n ? ipv6_frag_rcv (net\/ipv6\/reassembly.c:289 (discriminator 2) net\/ipv6\/reassembly.c:229 (discriminator 2) net\/ipv6\/reassembly.c:391 (discriminator 2))
\n ipv6_frag_rcv (net\/ipv6\/reassembly.c:289 (discriminator 2) net\/ipv6\/reassembly.c:229 (discriminator 2) net\/ipv6\/reassembly.c:391 (discriminator 2))
\n ip6_protocol_deliver_rcu (net\/ipv6\/ip6_input.c:479 (discriminator 5))
\n ip6_input_finish (net\/ipv6\/ip6_input.c:534)
\n ipv6_rcv (include\/net\/dst.h:480 (discriminator 3) net\/ipv6\/ip6_input.c:119 (discriminator 3) net\/ipv6\/ip6_input.c:109 (discriminator 3) include\/linux\/netfilter.h:325 (discriminator 3) include\/linux\/netfilter.h:319 (discriminator 3) net\/ipv6\/ip6_input.c:351 (discriminator 3))
\n packet_sendmsg (net\/packet\/af_packet.c:3110 net\/packet\/af_packet.c:3142)
\n __x64_sys_sendmmsg (net\/socket.c:2883 net\/socket.c:2880 net\/socket.c:2880)
\n The buggy address belongs to the object at ff110001039c6b40
\n which belongs to the cache skbuff_small_head of size 704
\n The buggy address is located 0 bytes to the right of
\n allocated 704-byte region [ff110001039c6b40, ff110001039c6e00)<\/p>\n
BUG: KASAN: slab-out-of-bounds in ip6_protocol_deliver_rcu (net\/ipv6\/ip6_input.c:423 (discriminator 1))
\n Read of size 1 at addr ff110001039c6e08 by task poc\/771
\n Call Trace:
\n ? ip6_protocol_deliver_rcu (net\/ipv6\/ip6_input.c:423 (discriminator 1))
\n ip6_protocol_deliver_rcu (net\/ipv6\/ip6_input.c:423 (discriminator 1))
\n ip6_input_finish (net\/ipv6\/ip6_input.c:534)
\n ipv6_rcv (include\/net\/dst.h:480 (discriminator 3) net\/ipv6\/ip6_input.c:119 (discriminator 3) net\/ipv6\/ip6_input.c:109 (discriminator 3) include\/linux\/netfilter.h:325 (discriminator 3) include\/linux\/netfilter.h:319 (discriminator 3) net\/ipv6\/ip6_input.c:351 (discriminator 3))
\n packet_sendmsg (net\/packet\/af_packet.c:3110 net\/packet\/af_packet.c:3142)
\n __x64_sys_sendmmsg (net\/socket.c:2883 net\/socket.c:2880 net\/socket.c:2880)
\n packet_sendmsg (net\/packet\/af_packet.c:2959 net\/packet\/af_packet.c:3053 net\/packet\/af_packet.c:3142)
\n __x64_sys_sendmmsg (net\/socket.c:2883 net\/socket.c:2880 net\/socket.c:2880)
\n The buggy address belongs to the object at ff110001039c6b40
\n which belongs to the cache skbuff_small_head of size 704
\n The buggy address is located 8 bytes to the right of
\n allocated 704-byte region [ff110001039c6b40, ff110001039c6e00)<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
inet: frags: invalidate queues before flushing them<\/p>\n
fqdir_pre_exit() flushes the skbs from incomplete queues without
\nchanging thei<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-29034","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/29034","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=29034"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=29034"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=29034"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}