From: Michael LeMay Date: Mon, 26 Jun 2006 07:24:54 +0000 (-0700) Subject: [PATCH] keys: allocate key serial numbers randomly X-Git-Tag: v2.6.18-rc1~813 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e51f6d343789a4f0a2a7587ad7ec7746969d5c1c;p=pandora-kernel.git [PATCH] keys: allocate key serial numbers randomly Cause key_alloc_serial() to generate key serial numbers randomly rather than in linear sequence. Using an linear sequence permits a covert communication channel to be established, in which one process can communicate with another by creating or not creating new keys within a certain timeframe. The second process can probe for the expected next key serial number and judge its existence by the error returned. This is a problem as the serial number namespace is globally shared between all tasks, regardless of their context. For more information on this topic, this old TCSEC guide is recommended: http://www.radium.ncsc.mil/tpep/library/rainbow/NCSC-TG-030.html Signed-off-by: Michael LeMay Signed-off-by: James Morris Signed-off-by: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed