[PATCH 01/26] audit: make filetype matching consistent with other filters

Eric Paris
2011-11-17T22:02:44Z

Every other filter that matches part of the inodes list collected by audit
will match against any of the inodes on that list. The filetype matching
however had a strange way of doing things. It allowed userspace to
indicated if it should match on the first of the second name collected by
the kernel. Name collection ordering seems like a kernel internal and
making userspace rules get that right just seems like a bad idea. As it
turns out the userspace audit writers had no idea it was doing this and
thus never overloaded the value field. The kernel always checked the first
name collected which for the tested rules was always correct.

This patch just makes the filetype matching like the major, minor, inode,
and LSM rules in that it will match against any of the names collected. It
also changes the rule validation to reject the old unused rule types.

Noone new it was there. Noone used it. Why keep around the extra code?

Signed-off-by: Eric Paris <eparis@redhat.com>
---

kernel/auditfilter.c | 4 ++--
kernel/auditsc.c | 19 +++++++++----------
2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index f8277c8..d94dde8 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -385,7 +385,7 @@ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
goto exit_free;
break;
case AUDIT_FILETYPE:
- if ((f->val & ~S_IFMT) > S_IFMT)
+ if (f->val & ~S_IFMT)
goto exit_free;
break;
case AUDIT_INODE:
@@ -536,7 +536,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
goto exit_free;
break;
case AUDIT_FILETYPE:
- if ((f->val & ~S_IFMT) > S_IFMT)
+ if (f->val & ~S_IFMT)
goto exit_free;
break;
default:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 47b7fc1..dc8e5f0 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -305,21 +305,20 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
}
}

-static int audit_match_filetype(struct audit_context *ctx, int which)
+static int audit_match_filetype(struct audit_context *ctx, int val)
{
- unsigned index = which & ~S_IFMT;
- mode_t mode = which & S_IFMT;
+ int index;
+ mode_t mode = (mode_t)val;

if (unlikely(!ctx))
return 0;

- if (index >= ctx->name_count)
- return 0;
- if (ctx->names[index].ino == -1)
- return 0;
- if ((ctx->names[index].mode ^ mode) & S_IFMT)
- return 0;
- return 1;
+ for (index = 0; index < ctx->name_count; index++) {
+ if ((ctx->names[index].ino != -1) &&
+ ((ctx->names[index].mode & S_IFMT) == mode))
+ return 1;
+ }
+ return 0;
}

/*