selinux: don't produce incorrect filename_trans_count

I thought I fixed the counting in filename_trans_read_helper() to count
the compat rule count correctly in the final version, but it's still
wrong. To really count the same thing as in the compat path, we'd need
to add up the cardinalities of stype bitmaps of all datums.

Since the kernel currently doesn't implement an ebitmap_cardinality()
function (and computing the proper count would just waste CPU cycles
anyway), just document that we use the field only in case of the old
format and stop updating it in filename_trans_read_helper().

Fixes: 430059024389 ("selinux: implement new format of filename transitions")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index ef8d5b46b05b25133e1268dd013dd2d1b55332a5..1c0041576643b0b473180db65d393b369f53258c 100644 (file)
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -2016,12 +2016,7 @@ static int filename_trans_read_helper(struct policydb *p, void *fp)
        if (rc)
                goto out;
 
-       rc = ebitmap_set_bit(&p->filename_trans_ttypes, ttype, 1);
-       if (rc)
-               return rc;
-
-       p->filename_trans_count += ndatum;
-       return 0;
+       return ebitmap_set_bit(&p->filename_trans_ttypes, ttype, 1);
 
 out:
        kfree(ft);
@@ -2051,7 +2046,7 @@ static int filename_trans_read(struct policydb *p, void *fp)
        nel = le32_to_cpu(buf[0]);
 
        if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
-               p->filename_trans_count = nel;
+               p->compat_filename_trans_count = nel;
                p->filename_trans = hashtab_create(filenametr_hash,
                                                   filenametr_cmp, (1 << 11));
                if (!p->filename_trans)
@@ -3568,7 +3563,7 @@ static int filename_trans_write(struct policydb *p, void *fp)
                return 0;
 
        if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
-               buf[0] = cpu_to_le32(p->filename_trans_count);
+               buf[0] = cpu_to_le32(p->compat_filename_trans_count);
                rc = put_entry(buf, sizeof(u32), 1, fp);
                if (rc)
                        return rc;

diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
index d3adb522d3f39f6a947e23cdff501c7abf81eec7..35dc6aa7904d56f66efc24ec836da9f59c562d17 100644 (file)
--- a/security/selinux/ss/policydb.h
+++ b/security/selinux/ss/policydb.h
@@ -270,7 +270,8 @@ struct policydb {
        struct ebitmap filename_trans_ttypes;
        /* actual set of filename_trans rules */
        struct hashtab *filename_trans;
-       u32 filename_trans_count;
+       /* only used if policyvers < POLICYDB_VERSION_COMP_FTRANS */
+       u32 compat_filename_trans_count;
 
        /* bools indexed by (value - 1) */
        struct cond_bool_datum **bool_val_to_struct;