Certain operations in Linux kernel before 2.2.19 on the x86 architecture copy the wrong number of bytes, which might allow attackers to modify memory, aka "User access asm bug on x86."
https://www.debian.org/security/2001/dsa-047
http://www.redhat.com/support/errata/RHSA-2001-047.html
http://www.linux.org.uk/VERSION/relnotes.2219.html
http://marc.info/?l=bugtraq&m=99013830726309&w=2
http://marc.info/?l=bugtraq&m=98775114228203&w=2
http://marc.info/?l=bugtraq&m=98759029811377&w=2
http://marc.info/?l=bugtraq&m=98684172109474&w=2
http://marc.info/?l=bugtraq&m=98653252326445&w=2