Candidate: CVE-2007-5500
References: 
 http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.23.y.git;a=commitdiff;h=36ef66c5d137b9a31fd8c35d236fb9e26ef74f97
Description: 
 wait_task_stopped: Check p->exit_state instead of TASK_TRACED
Ubuntu-Description: 
 Scott James Remnant discovered that the waitid function could be made
 to hang the system.  A local attacker could execute a specially crafted
 program which would leave the system unresponsive, resulting in a denial
 of service.
Notes: 
 kees> 2.6.15 does not actually lock up -- it just spins in userspace
 jmm> This was introduced with commit 14bf01bb0599c89fc7f426d20353b76e12555308
 jmm> 2.6.14 is the first major release to be affected, marking earlier versions N/A
Bugs: 
upstream: released (2.6.23.8)
linux-2.6: released (2.6.23-1)
2.6.18-etch-security: released (2.6.18.dfsg.1-13etch5) [bugfix/wait_task_stopped-hang.patch]
2.6.8-sarge-security: N/A
2.4.27-sarge-security: N/A
2.6.15-dapper-security: released (2.6.15-29.61)
2.6.17-edgy-security: released (2.6.17.1-12.42)
2.6.20-feisty-security: released (2.6.20-16.33)
2.6.22-gutsy-security: released (2.6.22-14.47)