Commit b297f0a2 authored by Daniel Glöckner's avatar Daniel Glöckner Committed by Ben Hutchings

ima: accept previously set IMA_NEW_FILE

commit 1ac202e9 upstream.

Modifying the attributes of a file makes ima_inode_post_setattr reset
the IMA cache flags. So if the file, which has just been created,
is opened a second time before the first file descriptor is closed,
verification fails since the security.ima xattr has not been written
yet. We therefore have to look at the IMA_NEW_FILE even if the file
already existed.

With this patch there should no longer be an error when cat tries to
open testfile:

$ rm -f testfile
$ ( echo test >&3 ; touch testfile ; cat testfile ) 3>testfile

A file being new is no reason to accept that it is missing a digital
signature demanded by the policy.
Signed-off-by: default avatarDaniel Glöckner <dg@emlix.com>
Signed-off-by: default avatarMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
parent ad4b000f
...@@ -195,10 +195,11 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, ...@@ -195,10 +195,11 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
cause = "missing-hash"; cause = "missing-hash";
status = INTEGRITY_NOLABEL; status = INTEGRITY_NOLABEL;
if (opened & FILE_CREATED) { if (opened & FILE_CREATED)
iint->flags |= IMA_NEW_FILE; iint->flags |= IMA_NEW_FILE;
if ((iint->flags & IMA_NEW_FILE) &&
!(iint->flags & IMA_DIGSIG_REQUIRED))
status = INTEGRITY_PASS; status = INTEGRITY_PASS;
}
goto out; goto out;
} }
......
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