Use the LSM ID number instead of the LSM name to identify which security module's attibute data should be shown in /proc/self/attr. The security_[gs]etprocattr() functions have been changed to expect the LSM ID. The change from a string comparison to an integer comparison in these functions will provide a minor performance improvement. Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Serge Hallyn <serge@xxxxxxxxxx> Reviewed-by: Mickael Salaun <mic@xxxxxxxxxxx> Reviewed-by: John Johansen <john.johansen@xxxxxxxxxxxxx> Cc: linux-fsdevel@xxxxxxxxxxxxxxx --- fs/proc/base.c | 29 +++++++++++++++-------------- fs/proc/internal.h | 2 +- include/linux/security.h | 11 +++++------ security/security.c | 15 +++++++-------- 4 files changed, 28 insertions(+), 29 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 9df3f4839662..42a02375fb5f 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -97,6 +97,7 @@ #include <linux/resctrl.h> #include <linux/cn_proc.h> #include <linux/ksm.h> +#include <uapi/linux/lsm.h> #include <trace/events/oom.h> #include "internal.h" #include "fd.h" @@ -146,10 +147,10 @@ struct pid_entry { NOD(NAME, (S_IFREG|(MODE)), \ NULL, &proc_single_file_operations, \ { .proc_show = show } ) -#define ATTR(LSM, NAME, MODE) \ +#define ATTR(LSMID, NAME, MODE) \ NOD(NAME, (S_IFREG|(MODE)), \ NULL, &proc_pid_attr_operations, \ - { .lsm = LSM }) + { .lsmid = LSMID }) /* * Count the number of hardlinks for the pid_entry table, excluding the . @@ -2730,7 +2731,7 @@ static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, if (!task) return -ESRCH; - length = security_getprocattr(task, PROC_I(inode)->op.lsm, + length = security_getprocattr(task, PROC_I(inode)->op.lsmid, file->f_path.dentry->d_name.name, &p); put_task_struct(task); @@ -2788,7 +2789,7 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, if (rv < 0) goto out_free; - rv = security_setprocattr(PROC_I(inode)->op.lsm, + rv = security_setprocattr(PROC_I(inode)->op.lsmid, file->f_path.dentry->d_name.name, page, count); mutex_unlock(¤t->signal->cred_guard_mutex); @@ -2837,27 +2838,27 @@ static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \ #ifdef CONFIG_SECURITY_SMACK static const struct pid_entry smack_attr_dir_stuff[] = { - ATTR("smack", "current", 0666), + ATTR(LSM_ID_SMACK, "current", 0666), }; LSM_DIR_OPS(smack); #endif #ifdef CONFIG_SECURITY_APPARMOR static const struct pid_entry apparmor_attr_dir_stuff[] = { - ATTR("apparmor", "current", 0666), - ATTR("apparmor", "prev", 0444), - ATTR("apparmor", "exec", 0666), + ATTR(LSM_ID_APPARMOR, "current", 0666), + ATTR(LSM_ID_APPARMOR, "prev", 0444), + ATTR(LSM_ID_APPARMOR, "exec", 0666), }; LSM_DIR_OPS(apparmor); #endif static const struct pid_entry attr_dir_stuff[] = { - ATTR(NULL, "current", 0666), - ATTR(NULL, "prev", 0444), - ATTR(NULL, "exec", 0666), - ATTR(NULL, "fscreate", 0666), - ATTR(NULL, "keycreate", 0666), - ATTR(NULL, "sockcreate", 0666), + ATTR(LSM_ID_UNDEF, "current", 0666), + ATTR(LSM_ID_UNDEF, "prev", 0444), + ATTR(LSM_ID_UNDEF, "exec", 0666), + ATTR(LSM_ID_UNDEF, "fscreate", 0666), + ATTR(LSM_ID_UNDEF, "keycreate", 0666), + ATTR(LSM_ID_UNDEF, "sockcreate", 0666), #ifdef CONFIG_SECURITY_SMACK DIR("smack", 0555, proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops), diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 9dda7e54b2d0..a889d9ef9584 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -92,7 +92,7 @@ union proc_op { int (*proc_show)(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *task); - const char *lsm; + int lsmid; }; struct proc_inode { diff --git a/include/linux/security.h b/include/linux/security.h index a20a4ceda6d9..b5fd3f7f4cd3 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -470,10 +470,9 @@ int security_sem_semctl(struct kern_ipc_perm *sma, int cmd); int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops, unsigned nsops, int alter); void security_d_instantiate(struct dentry *dentry, struct inode *inode); -int security_getprocattr(struct task_struct *p, const char *lsm, const char *name, +int security_getprocattr(struct task_struct *p, int lsmid, const char *name, char **value); -int security_setprocattr(const char *lsm, const char *name, void *value, - size_t size); +int security_setprocattr(int lsmid, const char *name, void *value, size_t size); int security_netlink_send(struct sock *sk, struct sk_buff *skb); int security_ismaclabel(const char *name); int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen); @@ -1332,14 +1331,14 @@ static inline void security_d_instantiate(struct dentry *dentry, struct inode *inode) { } -static inline int security_getprocattr(struct task_struct *p, const char *lsm, +static inline int security_getprocattr(struct task_struct *p, int lsmid, const char *name, char **value) { return -EINVAL; } -static inline int security_setprocattr(const char *lsm, char *name, - void *value, size_t size) +static inline int security_setprocattr(int lsmid, char *name, void *value, + size_t size) { return -EINVAL; } diff --git a/security/security.c b/security/security.c index 3c0342410531..82253294069c 100644 --- a/security/security.c +++ b/security/security.c @@ -3801,7 +3801,7 @@ EXPORT_SYMBOL(security_d_instantiate); /** * security_getprocattr() - Read an attribute for a task * @p: the task - * @lsm: LSM name + * @lsmid: LSM identification * @name: attribute name * @value: attribute value * @@ -3809,13 +3809,13 @@ EXPORT_SYMBOL(security_d_instantiate); * * Return: Returns the length of @value on success, a negative value otherwise. */ -int security_getprocattr(struct task_struct *p, const char *lsm, - const char *name, char **value) +int security_getprocattr(struct task_struct *p, int lsmid, const char *name, + char **value) { struct security_hook_list *hp; hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsmid->name)) + if (lsmid != 0 && lsmid != hp->lsmid->id) continue; return hp->hook.getprocattr(p, name, value); } @@ -3824,7 +3824,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm, /** * security_setprocattr() - Set an attribute for a task - * @lsm: LSM name + * @lsmid: LSM identification * @name: attribute name * @value: attribute value * @size: attribute value size @@ -3834,13 +3834,12 @@ int security_getprocattr(struct task_struct *p, const char *lsm, * * Return: Returns bytes written on success, a negative value otherwise. */ -int security_setprocattr(const char *lsm, const char *name, void *value, - size_t size) +int security_setprocattr(int lsmid, const char *name, void *value, size_t size) { struct security_hook_list *hp; hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsmid->name)) + if (lsmid != 0 && lsmid != hp->lsmid->id) continue; return hp->hook.setprocattr(name, value, size); } -- 2.41.0