e51f6d3437
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 <mdlemay@epoch.ncsc.mil> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| Makefile | ||
| compat.c | ||
| internal.h | ||
| key.c | ||
| keyctl.c | ||
| keyring.c | ||
| permission.c | ||
| proc.c | ||
| process_keys.c | ||
| request_key.c | ||
| request_key_auth.c | ||
| user_defined.c | ||