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author | David Howells <dhowells@redhat.com> | 2009-09-02 09:13:40 +0100 |
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committer | James Morris <jmorris@namei.org> | 2009-09-02 21:29:01 +1000 |
commit | e0e817392b9acf2c98d3be80c233dddb1b52003d (patch) | |
tree | ee680c020039313c9f9c40ab3542bb30a7363381 /lib/Kconfig.debug | |
parent | ed6d76e4c32de0c2ad5f1d572b948ef49e465176 (diff) | |
download | linux-stable-e0e817392b9acf2c98d3be80c233dddb1b52003d.tar.gz linux-stable-e0e817392b9acf2c98d3be80c233dddb1b52003d.tar.bz2 linux-stable-e0e817392b9acf2c98d3be80c233dddb1b52003d.zip |
CRED: Add some configurable debugging [try #6]
Add a config option (CONFIG_DEBUG_CREDENTIALS) to turn on some debug checking
for credential management. The additional code keeps track of the number of
pointers from task_structs to any given cred struct, and checks to see that
this number never exceeds the usage count of the cred struct (which includes
all references, not just those from task_structs).
Furthermore, if SELinux is enabled, the code also checks that the security
pointer in the cred struct is never seen to be invalid.
This attempts to catch the bug whereby inode_has_perm() faults in an nfsd
kernel thread on seeing cred->security be a NULL pointer (it appears that the
credential struct has been previously released):
http://www.kerneloops.org/oops.php?number=252883
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'lib/Kconfig.debug')
-rw-r--r-- | lib/Kconfig.debug | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 12327b2bb785..fbb87cf138c5 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -653,6 +653,21 @@ config DEBUG_NOTIFIERS This is a relatively cheap check but if you care about maximum performance, say N. +config DEBUG_CREDENTIALS + bool "Debug credential management" + depends on DEBUG_KERNEL + help + Enable this to turn on some debug checking for credential + management. The additional code keeps track of the number of + pointers from task_structs to any given cred struct, and checks to + see that this number never exceeds the usage count of the cred + struct. + + Furthermore, if SELinux is enabled, this also checks that the + security pointer in the cred struct is never seen to be invalid. + + If unsure, say N. + # # Select this config option from the architecture Kconfig, if it # it is preferred to always offer frame pointers as a config |