Bug#381905: linux-kernel-headers: NGROUPS_MAX doesn't match the kernel and causes test failures
Package: linux-kernel-headers
Version: 2.5.999-test7-bk-17
Severity: important
The setgroups test from the ltp (Linux Test Project
<http://ltp.sourceforge.net/>) testsuite has unexpected behavior on Debian
Sarge. The test fails reporting that setgroups() call succeeded when trying
to set more groups that NGROUPS_MAX.
We have tracked this down to a mismatch in the definitions of NGROUPS_MAX
between the 2.6.8 Debian kernel and the linux-kernel-headers package.
The linux-kernel-headers package defines this value as 32, while the
kernel defines it as 65535. When the test tries to retrieve this
maximum value using the sysconf() call, it gets the value of 32 that
was retrieved from glibc and specified by /usr/include/linux/limits.h,
which is part of the linux-kernel-headers package. The test then tries
to issue a setgroups() call with the number of groups set to NGROUPS_MAX+1 (33)
which is less then the kernel maximum (65535), and thus the call succeeds
when it should really fail.
It is important to specify proper limits for this. This is a request to set
NGROUPS_MAX to 65535, so it matches the kernel, in linux-kernel-headers
package.
-- System Information:
Debian Release: 3.1
Architecture: ia64
Kernel: Linux 2.6.8-3-mckinley-smp
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)
-- no debconf information
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