path: root/security
diff options
authorMimi Zohar <zohar@linux.vnet.ibm.com>2011-01-03 14:59:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-03 16:36:33 -0800
commit867c20265459d30a01b021a9c1e81fb4c5832aa9 (patch)
tree7873555d6a0e100fb1faa90da6e6366a430c3403 /security
parent03ed6a3aa600c48593c3984812fda2d5945ddb46 (diff)
ima: fix add LSM rule bug
If security_filter_rule_init() doesn't return a rule, then not everything is as fine as the return code implies. This bug only occurs when the LSM (eg. SELinux) is disabled at runtime. Adding an empty LSM rule causes ima_match_rules() to always succeed, ignoring any remaining rules. default IMA TCB policy: # PROC_SUPER_MAGIC dont_measure fsmagic=0x9fa0 # SYSFS_MAGIC dont_measure fsmagic=0x62656572 # DEBUGFS_MAGIC dont_measure fsmagic=0x64626720 # TMPFS_MAGIC dont_measure fsmagic=0x01021994 # SECURITYFS_MAGIC dont_measure fsmagic=0x73636673 < LSM specific rule > dont_measure obj_type=var_log_t measure func=BPRM_CHECK measure func=FILE_MMAP mask=MAY_EXEC measure func=FILE_CHECK mask=MAY_READ uid=0 Thus without the patch, with the boot parameters 'tcb selinux=0', adding the above 'dont_measure obj_type=var_log_t' rule to the default IMA TCB measurement policy, would result in nothing being measured. The patch prevents the default TCB policy from being replaced. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: David Safford <safford@watson.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'security')
1 files changed, 2 insertions, 0 deletions
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index aef8c0a923ab..d661afbe474c 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -253,6 +253,8 @@ static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry,
result = security_filter_rule_init(entry->lsm[lsm_rule].type,
Audit_equal, args,
+ if (!entry->lsm[lsm_rule].rule)
+ return -EINVAL;
return result;

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