Convert the kernel_ask_as hooks to use the lsm_export structure instead of a u32 secid. There is some scaffolding involved that will be removed when security_kernel_ask_as() is updated. Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> --- include/linux/lsm_hooks.h | 4 ++-- security/security.c | 15 ++++++++++++++- security/selinux/hooks.c | 17 ++++++++++++++--- security/smack/smack_lsm.c | 12 +++++++++++- 4 files changed, 41 insertions(+), 7 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 544671f44dfa..85b8217ce2f2 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -578,7 +578,7 @@ * @kernel_act_as: * Set the credentials for a kernel service to act as (subjective context). * @new points to the credentials to be modified. - * @secid specifies the security ID to be set + * @l specifies the security data to be set * The current task must be the one that nominated @secid. * Return 0 if successful. * @kernel_create_files_as: @@ -1606,7 +1606,7 @@ union security_list_options { gfp_t gfp); void (*cred_transfer)(struct cred *new, const struct cred *old); void (*cred_getsecid)(const struct cred *c, struct lsm_export *l); - int (*kernel_act_as)(struct cred *new, u32 secid); + int (*kernel_act_as)(struct cred *new, struct lsm_export *l); int (*kernel_create_files_as)(struct cred *new, struct inode *inode); int (*kernel_module_request)(char *kmod_name); int (*kernel_load_data)(enum kernel_load_data_id id); diff --git a/security/security.c b/security/security.c index 802557ff6f60..3a766755b722 100644 --- a/security/security.c +++ b/security/security.c @@ -742,6 +742,15 @@ static inline void lsm_export_secid(struct lsm_export *data, u32 *secid) } } +static inline void lsm_export_to_all(struct lsm_export *data, u32 secid) +{ + data->selinux = secid; + data->smack = secid; + data->apparmor = secid; + data->flags = LSM_EXPORT_SELINUX | LSM_EXPORT_SMACK | + LSM_EXPORT_APPARMOR; +} + /* Security operations */ int security_binder_set_context_mgr(struct task_struct *mgr) @@ -1647,7 +1656,11 @@ EXPORT_SYMBOL(security_cred_getsecid); int security_kernel_act_as(struct cred *new, u32 secid) { - return call_int_hook(kernel_act_as, 0, new, secid); + struct lsm_export data = { .flags = LSM_EXPORT_NONE }; + + lsm_export_to_all(&data, secid); + + return call_int_hook(kernel_act_as, 0, new, &data); } int security_kernel_create_files_as(struct cred *new, struct inode *inode) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index c82108793fb5..8d4334f68a65 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -222,6 +222,14 @@ static inline void selinux_export_secid(struct lsm_export *l, u32 secid) l->flags |= LSM_EXPORT_SELINUX; } +static inline void selinux_import_secid(struct lsm_export *l, u32 *secid) +{ + if (l->flags | LSM_EXPORT_SELINUX) + *secid = l->selinux; + else + *secid = SECSID_NULL; +} + /* * get the security ID of a set of credentials */ @@ -3773,19 +3781,22 @@ static void selinux_cred_getsecid(const struct cred *c, struct lsm_export *l) * set the security data for a kernel service * - all the creation contexts are set to unlabelled */ -static int selinux_kernel_act_as(struct cred *new, u32 secid) +static int selinux_kernel_act_as(struct cred *new, struct lsm_export *l) { struct task_security_struct *tsec = selinux_cred(new); + u32 nsid; u32 sid = current_sid(); int ret; + selinux_import_secid(l, &nsid); + ret = avc_has_perm(&selinux_state, - sid, secid, + sid, nsid, SECCLASS_KERNEL_SERVICE, KERNEL_SERVICE__USE_AS_OVERRIDE, NULL); if (ret == 0) { - tsec->sid = secid; + tsec->sid = nsid; tsec->create_sid = 0; tsec->keycreate_sid = 0; tsec->sockcreate_sid = 0; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 13ac3045a388..da85d607d40a 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -475,6 +475,14 @@ static inline void smack_export_secid(struct lsm_export *l, u32 secid) l->flags |= LSM_EXPORT_SMACK; } +static inline void smack_import_secid(struct lsm_export *l, u32 *secid) +{ + if (l->flags | LSM_EXPORT_SMACK) + *secid = l->smack; + else + *secid = 0; +} + /* * LSM hooks. * We he, that is fun! @@ -1997,10 +2005,12 @@ static void smack_cred_getsecid(const struct cred *cred, struct lsm_export *l) * * Set the security data for a kernel service. */ -static int smack_kernel_act_as(struct cred *new, u32 secid) +static int smack_kernel_act_as(struct cred *new, struct lsm_export *l) { + u32 secid; struct task_smack *new_tsp = smack_cred(new); + smack_import_secid(l, &secid); new_tsp->smk_task = smack_from_secid(secid); return 0; } -- 2.19.1