The cred_prepared bprm flag has a misleading name. It has nothing to do
with the bprm_prepare_cred hook, and actually tracks if bprm_set_creds has
been called. Rename this flag and improve its comment.

Cc: David Howells <dhowe...@redhat.com>
Cc: John Johansen <john.johan...@canonical.com>
Cc: Paul Moore <p...@paul-moore.com>
Cc: Stephen Smalley <s...@tycho.nsa.gov>
Cc: Casey Schaufler <ca...@schaufler-ca.com>
Cc: James Morris <james.l.mor...@oracle.com>
Signed-off-by: Kees Cook <keesc...@chromium.org>
Acked-by: John Johansen <john.johan...@canonical.com>
Acked-by: James Morris <james.l.mor...@oracle.com>
Acked-by: Paul Moore <p...@paul-moore.com>
Acked-by: Serge Hallyn <se...@hallyn.com>
---
 fs/binfmt_flat.c           | 2 +-
 fs/exec.c                  | 2 +-
 include/linux/binfmts.h    | 8 ++++++--
 security/apparmor/domain.c | 2 +-
 security/selinux/hooks.c   | 2 +-
 security/smack/smack_lsm.c | 2 +-
 security/tomoyo/tomoyo.c   | 2 +-
 7 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 2edcefc0a294..a722530cc468 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -885,7 +885,7 @@ static int load_flat_shared_library(int id, struct lib_info 
*libs)
         * as we're past the point of no return and are dealing with shared
         * libraries.
         */
-       bprm.cred_prepared = 1;
+       bprm.called_set_creds = 1;
 
        res = prepare_binprm(&bprm);
 
diff --git a/fs/exec.c b/fs/exec.c
index 72934df68471..cedae1620d2f 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1527,7 +1527,7 @@ int prepare_binprm(struct linux_binprm *bprm)
        retval = security_bprm_set_creds(bprm);
        if (retval)
                return retval;
-       bprm->cred_prepared = 1;
+       bprm->called_set_creds = 1;
 
        memset(bprm->buf, 0, BINPRM_BUF_SIZE);
        return kernel_read(bprm->file, 0, bprm->buf, BINPRM_BUF_SIZE);
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index 05488da3aee9..3cd98e8bc9dc 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -25,8 +25,12 @@ struct linux_binprm {
        struct mm_struct *mm;
        unsigned long p; /* current top of mem */
        unsigned int
-               cred_prepared:1,/* true if creds already prepared (multiple
-                                * preps happen for interpreters) */
+               /*
+                * True after the bprm_set_creds hook has been called once
+                * (multiple calls can be made via prepare_binprm() for
+                * binfmt_script/misc).
+                */
+               called_set_creds:1,
                cap_effective:1;/* true if has elevated effective capabilities,
                                 * false if not; except for init which inherits
                                 * its parent's caps anyway */
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index 001e133a3c8c..878407e023e3 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -350,7 +350,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
        const char *name = NULL, *info = NULL;
        int error = 0;
 
-       if (bprm->cred_prepared)
+       if (bprm->called_set_creds)
                return 0;
 
        ctx = cred_ctx(bprm->cred);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index e67a526d1f30..5d4051541518 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2328,7 +2328,7 @@ static int selinux_bprm_set_creds(struct linux_binprm 
*bprm)
 
        /* SELinux context only depends on initial program or script and not
         * the script interpreter */
-       if (bprm->cred_prepared)
+       if (bprm->called_set_creds)
                return 0;
 
        old_tsec = current_security();
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 658f5d8c7e76..7d4b2e221124 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -917,7 +917,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm)
        struct superblock_smack *sbsp;
        int rc;
 
-       if (bprm->cred_prepared)
+       if (bprm->called_set_creds)
                return 0;
 
        isp = inode->i_security;
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 130b4fa4f65f..d25b705360e0 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -76,7 +76,7 @@ static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
         * Do only if this function is called for the first time of an execve
         * operation.
         */
-       if (bprm->cred_prepared)
+       if (bprm->called_set_creds)
                return 0;
 #ifndef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER
        /*
-- 
2.7.4

Reply via email to