[PATCH v3 4/9] proc: Use lsmids instead of lsm names for attrs
From: Casey Schaufler <casey@schaufler-ca.com>
Date: 2022-11-23 20:19:00
Also in:
linux-security-module, lkml
Subsystem:
filesystems (vfs and infrastructure), proc filesystem, security subsystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
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@schaufler-ca.com> --- fs/proc/base.c | 29 +++++++++++++++-------------- fs/proc/internal.h | 2 +- include/linux/security.h | 11 +++++------ security/security.c | 11 +++++------ 4 files changed, 26 insertions(+), 27 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9e479d7d202b..e3dfcb9d68f2 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c@@ -96,6 +96,7 @@ #include <linux/time_namespace.h> #include <linux/resctrl.h> #include <linux/cn_proc.h> +#include <uapi/linux/lsm.h> #include <trace/events/oom.h> #include "internal.h" #include "fd.h"
@@ -145,10 +146,10 @@ 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_INVALID, "current", 0666), + ATTR(LSM_ID_INVALID, "prev", 0444), + ATTR(LSM_ID_INVALID, "exec", 0666), + ATTR(LSM_ID_INVALID, "fscreate", 0666), + ATTR(LSM_ID_INVALID, "keycreate", 0666), + ATTR(LSM_ID_INVALID, "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 b701d0207edf..18db9722c81b 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 5b7d486ae1f3..ed2aae04db3b 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h@@ -482,10 +482,9 @@ 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);
@@ -1326,14 +1325,14 @@ 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 6e8ed58423d7..7d6e4f788f93 100644
--- a/security/security.c
+++ b/security/security.c@@ -2082,26 +2082,25 @@ void security_d_instantiate(struct dentry *dentry, struct inode *inode) } EXPORT_SYMBOL(security_d_instantiate); -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->lsm)) + if (lsmid != LSM_ID_INVALID && lsmid != hp->lsmid->id) continue; return hp->hook.getprocattr(p, name, value); } return LSM_RET_DEFAULT(getprocattr); } -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->lsm)) + if (lsmid != LSM_ID_INVALID && lsmid != hp->lsmid->id) continue; return hp->hook.setprocattr(name, value, size); }
--
2.38.1