Description · from the CVE record
In the Linux kernel, the following vulnerability has been resolved:
vxlan: use pskb_network_may_pull() in route_shortcircuit()
route_shortcircuit() currently calls pskb_may_pull(skb, sizeof(struct iphdr))
(or ipv6hdr), which checks if bytes are available starting from skb->data.
However, in vxlan_xmit(), skb->data points to the MAC header, so
skb_network_offset(skb) is ETH_HLEN (14 bytes). Using pskb_may_pull(skb, 20)
only checks 20 bytes from skb->data (which is 14 bytes MAC header + 6 bytes of
IP header), leaving the rest of the IP header potentially un-pulled in non-linear
frags. Subsequent dereferences of ip_hdr(skb)->daddr can read beyond the pulled
linear buffer length.
Fix this by using pskb_network_may_pull(), which adds skb_network_offset(skb) to
the length check to ensure the full network header is present in the linear buffer.
Affected
ProductAffectedFixed inSource
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < c419af4924c1593500a40519730ed98575d04a3ec419af4924c1593500a40519730ed98575d04a3eCNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < 6bd0a3a1b5744166946f0c551a6665c3b46b05e46bd0a3a1b5744166946f0c551a6665c3b46b05e4CNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < 214ba43faf106cb06cd3dd30999c5c809c868b53214ba43faf106cb06cd3dd30999c5c809c868b53CNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < 42887be7c4cf283cce02cd0fb6411221167c8b6c42887be7c4cf283cce02cd0fb6411221167c8b6cCNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < aa0d31376d574ac858a40078431a77127bf04ee4aa0d31376d574ac858a40078431a77127bf04ee4CNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < ee799977d7941dbfb11049e17edd9eaf4f8820f7ee799977d7941dbfb11049e17edd9eaf4f8820f7CNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < 4f3f96e771a20263635bb5e1307c112d613b4bbd4f3f96e771a20263635bb5e1307c112d613b4bbdCNA
Linuxe4f67addf158f98f8197e08974966b18480dc751 – < 26bb2dd0a8839617e2c79ffbbe1923f8e4bab9fb26bb2dd0a8839617e2c79ffbbe1923f8e4bab9fbCNA
Linux3.8–CNA
by Kastro