Convert the inode_getsecid hooks to use the lsm_export structure instead of a u32 secid. There is some scaffolding involved that will be removed when security_inode_getsecid() is updated. Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> --- include/linux/lsm_hooks.h | 4 ++-- include/linux/security.h | 5 +++++ security/security.c | 35 ++++++++++++++++++++++++++++++++++- security/selinux/hooks.c | 21 ++++++++++++++++----- security/smack/smack_lsm.c | 13 +++++++++++-- 5 files changed, 68 insertions(+), 10 deletions(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index f19751dc53be..ff97f57a87bb 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -409,7 +409,7 @@ * @inode_getsecid: * Get the secid associated with the node. * @inode contains a pointer to the inode. - * @secid contains a pointer to the location where result will be saved. + * @data contains a pointer to the location where result will be saved. * In case of failure, @secid will be set to zero. * @inode_copy_up: * A file is about to be copied up from lower layer to upper layer of @@ -1556,7 +1556,7 @@ union security_list_options { int flags); int (*inode_listsecurity)(struct inode *inode, char *buffer, size_t buffer_size); - void (*inode_getsecid)(struct inode *inode, u32 *secid); + void (*inode_getsecid)(struct inode *inode, struct lsm_export *data); int (*inode_copy_up)(struct dentry *src, struct cred **new); int (*inode_copy_up_xattr)(const char *name); diff --git a/include/linux/security.h b/include/linux/security.h index a79fe8ef9d84..785d21c81dea 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -85,6 +85,11 @@ struct lsm_export { #define LSM_EXPORT_SMACK 0x02 #define LSM_EXPORT_APPARMOR 0x04 +static inline void lsm_export_init(struct lsm_export *l) +{ + memset(l, 0, sizeof(*l)); +} + /* These functions are in security/commoncap.c */ extern int cap_capable(const struct cred *cred, struct user_namespace *ns, int cap, unsigned int opts); diff --git a/security/security.c b/security/security.c index 750b1b63edbb..5bee7e0b0bf3 100644 --- a/security/security.c +++ b/security/security.c @@ -708,6 +708,36 @@ int lsm_superblock_alloc(struct super_block *sb) RC; \ }) +/** + * lsm_export_secid - pull the useful secid out of a lsm_export + * @data: the containing data structure + * @secid: where to put the one that matters. + * + * Shim that will disappear when all lsm_export conversions are done. + */ +static inline void lsm_export_secid(struct lsm_export *data, u32 *secid) +{ + switch (data->flags) { + case LSM_EXPORT_NONE: + *secid = 0; + break; + case LSM_EXPORT_SELINUX: + *secid = data->selinux; + break; + case LSM_EXPORT_SMACK: + *secid = data->smack; + break; + case LSM_EXPORT_APPARMOR: + *secid = data->apparmor; + break; + default: + pr_warn("%s flags=0x%u - not a valid set\n", __func__, + data->flags); + *secid = 0; + break; + } +} + /* Security operations */ int security_binder_set_context_mgr(struct task_struct *mgr) @@ -1375,7 +1405,10 @@ EXPORT_SYMBOL(security_inode_listsecurity); void security_inode_getsecid(struct inode *inode, u32 *secid) { - call_void_hook(inode_getsecid, inode, secid); + struct lsm_export data = { .flags = LSM_EXPORT_NONE }; + + call_void_hook(inode_getsecid, inode, &data); + lsm_export_secid(&data, secid); } int security_inode_copy_up(struct dentry *src, struct cred **new) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 54b8a42ed3a3..cbf7bf3fa4af 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -211,6 +211,15 @@ static void cred_init_security(void) tsec->osid = tsec->sid = SECINITSID_KERNEL; } +/* + * Set the SELinux secid in an lsm_export structure + */ +static inline void selinux_export_secid(struct lsm_export *l, u32 secid) +{ + l->selinux = secid; + l->flags |= LSM_EXPORT_SELINUX; +} + /* * get the security ID of a set of credentials */ @@ -3212,15 +3221,16 @@ static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t return len; } -static void selinux_inode_getsecid(struct inode *inode, u32 *secid) +static void selinux_inode_getsecid(struct inode *inode, struct lsm_export *l) { struct inode_security_struct *isec = inode_security_novalidate(inode); - *secid = isec->sid; + + selinux_export_secid(l, isec->sid); } static int selinux_inode_copy_up(struct dentry *src, struct cred **new) { - u32 sid; + struct lsm_export l; struct task_security_struct *tsec; struct cred *new_creds = *new; @@ -3232,8 +3242,9 @@ static int selinux_inode_copy_up(struct dentry *src, struct cred **new) tsec = selinux_cred(new_creds); /* Get label from overlay inode and set it in create_sid */ - selinux_inode_getsecid(d_inode(src), &sid); - tsec->create_sid = sid; + lsm_export_init(&l); + selinux_inode_getsecid(d_inode(src), &l); + tsec->create_sid = l.selinux; *new = new_creds; return 0; } diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index d748c709f31a..a9277a942ca2 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -464,6 +464,15 @@ static int smk_ptrace_rule_check(struct task_struct *tracer, return rc; } +/* + * Set the Smack secid in an lsm_export structure + */ +static inline void smack_export_secid(struct lsm_export *l, u32 secid) +{ + l->smack = secid; + l->flags |= LSM_EXPORT_SMACK; +} + /* * LSM hooks. * We he, that is fun! @@ -1394,11 +1403,11 @@ static int smack_inode_listsecurity(struct inode *inode, char *buffer, * @inode: inode to extract the info from * @secid: where result will be saved */ -static void smack_inode_getsecid(struct inode *inode, u32 *secid) +static void smack_inode_getsecid(struct inode *inode, struct lsm_export *l) { struct smack_known *skp = smk_of_inode(inode); - *secid = skp->smk_secid; + smack_export_secid(l, skp->smk_secid); } /* -- 2.17.0