DEBIAN-CVE-2026-80634

In the Linux kernel, the following vulnerability has been resolved:  netfilter: flowtable: avoid numencaps underflow on bridge VLAN untag  The DEVPATHBRVLANUNTAG case post-decrements info->numencaps inside WARNONONCE(). numencaps is u8, so if it's already 0 the decrement still happens and wraps it to 255. The break only leaves the inner switch -- a later path entry can set info->indev back to a real device, and we end up returning with numencaps == 255.  nftdevforwardpath() then walks info.encap[] (size 2) up to numencaps, which means an OOB stack read and a bogus count copied into the route descriptor.  Should only happen on a malformed bridge path stack, hence the WARN, but worth handling sanely. Move the decrement out of the WARN.  [ While at this, remove the WARNONONCE since this can only happen   with a buggy bridge path stack --pablo ].