[PATCH v38 05/39] proc: Use lsmids instead of lsm names for attrs
Casey Schaufler
casey at schaufler-ca.com
Tue Sep 27 19:53:47 UTC 2022
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 at 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 93f7e3d971e4..b2bda7d0619f 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 .
@@ -2727,7 +2728,7 @@ 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,
(char*)file->f_path.dentry->d_name.name,
&p);
put_task_struct(task);
@@ -2785,7 +2786,7 @@ 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);
@@ -2834,27 +2835,27 @@ 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 06a80f78433d..3f6f4a7a1498 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -87,7 +87,7 @@ 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 abdd151fc720..c4696f14daac 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -478,10 +478,9 @@ 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, char *name,
+int security_getprocattr(struct task_struct *p, int lsmid, 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);
@@ -1317,14 +1316,14 @@ 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,
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 14f22d9c9d84..af62f4c1cc89 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2075,26 +2075,25 @@ 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, char *name,
- char **value)
+int security_getprocattr(struct task_struct *p, int lsmid, 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);
}
--
2.37.3
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