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authorJames Morris <jmorris@namei.org>2009-09-11 08:04:49 +1000
committerJames Morris <jmorris@namei.org>2009-09-11 08:04:49 +1000
commita3c8b97396ef42edfb845788ba6f53b2a93ce980 (patch)
tree530c5bdbc534618311dab3e0af245835af56db0f /include
parent74fca6a42863ffacaf7ba6f1936a9f228950f657 (diff)
parent9f0ab4a3f0fdb1ff404d150618ace2fa069bb2e1 (diff)
Merge branch 'next' into for-linus
Diffstat (limited to 'include')
-rw-r--r--include/linux/cred.h69
-rw-r--r--include/linux/key.h8
-rw-r--r--include/linux/keyctl.h1
-rw-r--r--include/linux/lsm_audit.h12
-rw-r--r--include/linux/sched.h3
-rw-r--r--include/linux/security.h154
-rw-r--r--include/linux/xattr.h1
7 files changed, 234 insertions, 14 deletions
diff --git a/include/linux/cred.h b/include/linux/cred.h
index 4fa999696310..24520a539c6f 100644
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -114,6 +114,13 @@ struct thread_group_cred {
*/
struct cred {
atomic_t usage;
+#ifdef CONFIG_DEBUG_CREDENTIALS
+ atomic_t subscribers; /* number of processes subscribed */
+ void *put_addr;
+ unsigned magic;
+#define CRED_MAGIC 0x43736564
+#define CRED_MAGIC_DEAD 0x44656144
+#endif
uid_t uid; /* real UID of the task */
gid_t gid; /* real GID of the task */
uid_t suid; /* saved UID of the task */
@@ -143,7 +150,9 @@ struct cred {
};
extern void __put_cred(struct cred *);
+extern void exit_creds(struct task_struct *);
extern int copy_creds(struct task_struct *, unsigned long);
+extern struct cred *cred_alloc_blank(void);
extern struct cred *prepare_creds(void);
extern struct cred *prepare_exec_creds(void);
extern struct cred *prepare_usermodehelper_creds(void);
@@ -158,6 +167,60 @@ extern int set_security_override_from_ctx(struct cred *, const char *);
extern int set_create_files_as(struct cred *, struct inode *);
extern void __init cred_init(void);
+/*
+ * check for validity of credentials
+ */
+#ifdef CONFIG_DEBUG_CREDENTIALS
+extern void __invalid_creds(const struct cred *, const char *, unsigned);
+extern void __validate_process_creds(struct task_struct *,
+ const char *, unsigned);
+
+static inline bool creds_are_invalid(const struct cred *cred)
+{
+ if (cred->magic != CRED_MAGIC)
+ return true;
+ if (atomic_read(&cred->usage) < atomic_read(&cred->subscribers))
+ return true;
+#ifdef CONFIG_SECURITY_SELINUX
+ if ((unsigned long) cred->security < PAGE_SIZE)
+ return true;
+ if ((*(u32*)cred->security & 0xffffff00) ==
+ (POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8))
+ return true;
+#endif
+ return false;
+}
+
+static inline void __validate_creds(const struct cred *cred,
+ const char *file, unsigned line)
+{
+ if (unlikely(creds_are_invalid(cred)))
+ __invalid_creds(cred, file, line);
+}
+
+#define validate_creds(cred) \
+do { \
+ __validate_creds((cred), __FILE__, __LINE__); \
+} while(0)
+
+#define validate_process_creds() \
+do { \
+ __validate_process_creds(current, __FILE__, __LINE__); \
+} while(0)
+
+extern void validate_creds_for_do_exit(struct task_struct *);
+#else
+static inline void validate_creds(const struct cred *cred)
+{
+}
+static inline void validate_creds_for_do_exit(struct task_struct *tsk)
+{
+}
+static inline void validate_process_creds(void)
+{
+}
+#endif
+
/**
* get_new_cred - Get a reference on a new set of credentials
* @cred: The new credentials to reference
@@ -186,7 +249,9 @@ static inline struct cred *get_new_cred(struct cred *cred)
*/
static inline const struct cred *get_cred(const struct cred *cred)
{
- return get_new_cred((struct cred *) cred);
+ struct cred *nonconst_cred = (struct cred *) cred;
+ validate_creds(cred);
+ return get_new_cred(nonconst_cred);
}
/**
@@ -204,7 +269,7 @@ static inline void put_cred(const struct cred *_cred)
{
struct cred *cred = (struct cred *) _cred;
- BUG_ON(atomic_read(&(cred)->usage) <= 0);
+ validate_creds(cred);
if (atomic_dec_and_test(&(cred)->usage))
__put_cred(cred);
}
diff --git a/include/linux/key.h b/include/linux/key.h
index e544f466d69a..cd50dfa1d4c2 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -129,7 +129,10 @@ struct key {
struct rw_semaphore sem; /* change vs change sem */
struct key_user *user; /* owner of this key */
void *security; /* security data for this key */
- time_t expiry; /* time at which key expires (or 0) */
+ union {
+ time_t expiry; /* time at which key expires (or 0) */
+ time_t revoked_at; /* time at which key was revoked */
+ };
uid_t uid;
gid_t gid;
key_perm_t perm; /* access permissions */
@@ -275,6 +278,8 @@ static inline key_serial_t key_serial(struct key *key)
extern ctl_table key_sysctls[];
#endif
+extern void key_replace_session_keyring(void);
+
/*
* the userspace interface
*/
@@ -297,6 +302,7 @@ extern void key_init(void);
#define key_fsuid_changed(t) do { } while(0)
#define key_fsgid_changed(t) do { } while(0)
#define key_init() do { } while(0)
+#define key_replace_session_keyring() do { } while(0)
#endif /* CONFIG_KEYS */
#endif /* __KERNEL__ */
diff --git a/include/linux/keyctl.h b/include/linux/keyctl.h
index c0688eb72093..bd383f1944fb 100644
--- a/include/linux/keyctl.h
+++ b/include/linux/keyctl.h
@@ -52,5 +52,6 @@
#define KEYCTL_SET_TIMEOUT 15 /* set key timeout */
#define KEYCTL_ASSUME_AUTHORITY 16 /* assume request_key() authorisation */
#define KEYCTL_GET_SECURITY 17 /* get key security label */
+#define KEYCTL_SESSION_TO_PARENT 18 /* apply session keyring to parent process */
#endif /* _LINUX_KEYCTL_H */
diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h
index e461b2c3d711..190c37854870 100644
--- a/include/linux/lsm_audit.h
+++ b/include/linux/lsm_audit.h
@@ -33,6 +33,7 @@ struct common_audit_data {
#define LSM_AUDIT_DATA_IPC 4
#define LSM_AUDIT_DATA_TASK 5
#define LSM_AUDIT_DATA_KEY 6
+#define LSM_AUDIT_NO_AUDIT 7
struct task_struct *tsk;
union {
struct {
@@ -66,16 +67,19 @@ struct common_audit_data {
} key_struct;
#endif
} u;
- const char *function;
/* this union contains LSM specific data */
union {
+#ifdef CONFIG_SECURITY_SMACK
/* SMACK data */
struct smack_audit_data {
+ const char *function;
char *subject;
char *object;
char *request;
int result;
} smack_audit_data;
+#endif
+#ifdef CONFIG_SECURITY_SELINUX
/* SELinux data */
struct {
u32 ssid;
@@ -83,10 +87,12 @@ struct common_audit_data {
u16 tclass;
u32 requested;
u32 audited;
+ u32 denied;
struct av_decision *avd;
int result;
} selinux_audit_data;
- } lsm_priv;
+#endif
+ };
/* these callback will be implemented by a specific LSM */
void (*lsm_pre_audit)(struct audit_buffer *, void *);
void (*lsm_post_audit)(struct audit_buffer *, void *);
@@ -104,7 +110,7 @@ int ipv6_skb_to_auditdata(struct sk_buff *skb,
/* Initialize an LSM audit data structure. */
#define COMMON_AUDIT_DATA_INIT(_d, _t) \
{ memset((_d), 0, sizeof(struct common_audit_data)); \
- (_d)->type = LSM_AUDIT_DATA_##_t; (_d)->function = __func__; }
+ (_d)->type = LSM_AUDIT_DATA_##_t; }
void common_lsm_audit(struct common_audit_data *a);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 0f1ea4a66957..9304027673b0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1292,6 +1292,7 @@ struct task_struct {
struct mutex cred_guard_mutex; /* guard against foreign influences on
* credential calculations
* (notably. ptrace) */
+ struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
char comm[TASK_COMM_LEN]; /* executable name excluding path
- access with [gs]et_task_comm (which lock
@@ -2077,7 +2078,7 @@ static inline unsigned long wait_task_inactive(struct task_struct *p,
#define for_each_process(p) \
for (p = &init_task ; (p = next_task(p)) != &init_task ; )
-extern bool is_single_threaded(struct task_struct *);
+extern bool current_is_single_threaded(void);
/*
* Careful: do_each_thread/while_each_thread is a double loop so
diff --git a/include/linux/security.h b/include/linux/security.h
index 1f16eea2017b..d050b66ab9ef 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -53,7 +53,7 @@ struct audit_krule;
extern int cap_capable(struct task_struct *tsk, const struct cred *cred,
int cap, int audit);
extern int cap_settime(struct timespec *ts, struct timezone *tz);
-extern int cap_ptrace_may_access(struct task_struct *child, unsigned int mode);
+extern int cap_ptrace_access_check(struct task_struct *child, unsigned int mode);
extern int cap_ptrace_traceme(struct task_struct *parent);
extern int cap_capget(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted);
extern int cap_capset(struct cred *new, const struct cred *old,
@@ -653,6 +653,11 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* manual page for definitions of the @clone_flags.
* @clone_flags contains the flags indicating what should be shared.
* Return 0 if permission is granted.
+ * @cred_alloc_blank:
+ * @cred points to the credentials.
+ * @gfp indicates the atomicity of any memory allocations.
+ * Only allocate sufficient memory and attach to @cred such that
+ * cred_transfer() will not get ENOMEM.
* @cred_free:
* @cred points to the credentials.
* Deallocate and clear the cred->security field in a set of credentials.
@@ -665,6 +670,10 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* @new points to the new credentials.
* @old points to the original credentials.
* Install a new set of credentials.
+ * @cred_transfer:
+ * @new points to the new credentials.
+ * @old points to the original credentials.
+ * Transfer data from original creds to new creds
* @kernel_act_as:
* Set the credentials for a kernel service to act as (subjective context).
* @new points to the credentials to be modified.
@@ -678,6 +687,10 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* @inode points to the inode to use as a reference.
* The current task must be the one that nominated @inode.
* Return 0 if successful.
+ * @kernel_module_request:
+ * Ability to trigger the kernel to automatically upcall to userspace for
+ * userspace to load a kernel module with the given name.
+ * Return 0 if successful.
* @task_setuid:
* Check permission before setting one or more of the user identity
* attributes of the current process. The @flags parameter indicates
@@ -994,6 +1007,17 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* Sets the connection's peersid to the secmark on skb.
* @req_classify_flow:
* Sets the flow's sid to the openreq sid.
+ * @tun_dev_create:
+ * Check permissions prior to creating a new TUN device.
+ * @tun_dev_post_create:
+ * This hook allows a module to update or allocate a per-socket security
+ * structure.
+ * @sk contains the newly created sock structure.
+ * @tun_dev_attach:
+ * Check permissions prior to attaching to a persistent TUN device. This
+ * hook can also be used by the module to update any security state
+ * associated with the TUN device's sock structure.
+ * @sk contains the existing sock structure.
*
* Security hooks for XFRM operations.
*
@@ -1088,6 +1112,13 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* Return the length of the string (including terminating NUL) or -ve if
* an error.
* May also return 0 (and a NULL buffer pointer) if there is no label.
+ * @key_session_to_parent:
+ * Forcibly assign the session keyring from a process to its parent
+ * process.
+ * @cred: Pointer to process's credentials
+ * @parent_cred: Pointer to parent process's credentials
+ * @keyring: Proposed new session keyring
+ * Return 0 if permission is granted, -ve error otherwise.
*
* Security hooks affecting all System V IPC operations.
*
@@ -1229,7 +1260,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* @alter contains the flag indicating whether changes are to be made.
* Return 0 if permission is granted.
*
- * @ptrace_may_access:
+ * @ptrace_access_check:
* Check permission before allowing the current process to trace the
* @child process.
* Security modules may also want to perform a process tracing check
@@ -1244,7 +1275,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* Check that the @parent process has sufficient permission to trace the
* current process before allowing the current process to present itself
* to the @parent process for tracing.
- * The parent process will still have to undergo the ptrace_may_access
+ * The parent process will still have to undergo the ptrace_access_check
* checks before it is allowed to trace this one.
* @parent contains the task_struct structure for debugger process.
* Return 0 if permission is granted.
@@ -1351,12 +1382,47 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* audit_rule_init.
* @rule contains the allocated rule
*
+ * @inode_notifysecctx:
+ * Notify the security module of what the security context of an inode
+ * should be. Initializes the incore security context managed by the
+ * security module for this inode. Example usage: NFS client invokes
+ * this hook to initialize the security context in its incore inode to the
+ * value provided by the server for the file when the server returned the
+ * file's attributes to the client.
+ *
+ * Must be called with inode->i_mutex locked.
+ *
+ * @inode we wish to set the security context of.
+ * @ctx contains the string which we wish to set in the inode.
+ * @ctxlen contains the length of @ctx.
+ *
+ * @inode_setsecctx:
+ * Change the security context of an inode. Updates the
+ * incore security context managed by the security module and invokes the
+ * fs code as needed (via __vfs_setxattr_noperm) to update any backing
+ * xattrs that represent the context. Example usage: NFS server invokes
+ * this hook to change the security context in its incore inode and on the
+ * backing filesystem to a value provided by the client on a SETATTR
+ * operation.
+ *
+ * Must be called with inode->i_mutex locked.
+ *
+ * @dentry contains the inode we wish to set the security context of.
+ * @ctx contains the string which we wish to set in the inode.
+ * @ctxlen contains the length of @ctx.
+ *
+ * @inode_getsecctx:
+ * Returns a string containing all relavent security context information
+ *
+ * @inode we wish to set the security context of.
+ * @ctx is a pointer in which to place the allocated security context.
+ * @ctxlen points to the place to put the length of @ctx.
* This is the main security structure.
*/
struct security_operations {
char name[SECURITY_NAME_MAX + 1];
- int (*ptrace_may_access) (struct task_struct *child, unsigned int mode);
+ int (*ptrace_access_check) (struct task_struct *child, unsigned int mode);
int (*ptrace_traceme) (struct task_struct *parent);
int (*capget) (struct task_struct *target,
kernel_cap_t *effective,
@@ -1483,12 +1549,15 @@ struct security_operations {
int (*dentry_open) (struct file *file, const struct cred *cred);
int (*task_create) (unsigned long clone_flags);
+ int (*cred_alloc_blank) (struct cred *cred, gfp_t gfp);
void (*cred_free) (struct cred *cred);
int (*cred_prepare)(struct cred *new, const struct cred *old,
gfp_t gfp);
void (*cred_commit)(struct cred *new, const struct cred *old);
+ void (*cred_transfer)(struct cred *new, const struct cred *old);
int (*kernel_act_as)(struct cred *new, u32 secid);
int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
+ int (*kernel_module_request)(void);
int (*task_setuid) (uid_t id0, uid_t id1, uid_t id2, int flags);
int (*task_fix_setuid) (struct cred *new, const struct cred *old,
int flags);
@@ -1556,6 +1625,10 @@ struct security_operations {
int (*secctx_to_secid) (const char *secdata, u32 seclen, u32 *secid);
void (*release_secctx) (char *secdata, u32 seclen);
+ int (*inode_notifysecctx)(struct inode *inode, void *ctx, u32 ctxlen);
+ int (*inode_setsecctx)(struct dentry *dentry, void *ctx, u32 ctxlen);
+ int (*inode_getsecctx)(struct inode *inode, void **ctx, u32 *ctxlen);
+
#ifdef CONFIG_SECURITY_NETWORK
int (*unix_stream_connect) (struct socket *sock,
struct socket *other, struct sock *newsk);
@@ -1592,6 +1665,9 @@ struct security_operations {
void (*inet_csk_clone) (struct sock *newsk, const struct request_sock *req);
void (*inet_conn_established) (struct sock *sk, struct sk_buff *skb);
void (*req_classify_flow) (const struct request_sock *req, struct flowi *fl);
+ int (*tun_dev_create)(void);
+ void (*tun_dev_post_create)(struct sock *sk);
+ int (*tun_dev_attach)(struct sock *sk);
#endif /* CONFIG_SECURITY_NETWORK */
#ifdef CONFIG_SECURITY_NETWORK_XFRM
@@ -1620,6 +1696,9 @@ struct security_operations {
const struct cred *cred,
key_perm_t perm);
int (*key_getsecurity)(struct key *key, char **_buffer);
+ int (*key_session_to_parent)(const struct cred *cred,
+ const struct cred *parent_cred,
+ struct key *key);
#endif /* CONFIG_KEYS */
#ifdef CONFIG_AUDIT
@@ -1637,7 +1716,7 @@ extern int security_module_enable(struct security_operations *ops);
extern int register_security(struct security_operations *ops);
/* Security operations */
-int security_ptrace_may_access(struct task_struct *child, unsigned int mode);
+int security_ptrace_access_check(struct task_struct *child, unsigned int mode);
int security_ptrace_traceme(struct task_struct *parent);
int security_capget(struct task_struct *target,
kernel_cap_t *effective,
@@ -1736,11 +1815,14 @@ int security_file_send_sigiotask(struct task_struct *tsk,
int security_file_receive(struct file *file);
int security_dentry_open(struct file *file, const struct cred *cred);
int security_task_create(unsigned long clone_flags);
+int security_cred_alloc_blank(struct cred *cred, gfp_t gfp);
void security_cred_free(struct cred *cred);
int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
void security_commit_creds(struct cred *new, const struct cred *old);
+void security_transfer_creds(struct cred *new, const struct cred *old);
int security_kernel_act_as(struct cred *new, u32 secid);
int security_kernel_create_files_as(struct cred *new, struct inode *inode);
+int security_kernel_module_request(void);
int security_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags);
int security_task_fix_setuid(struct cred *new, const struct cred *old,
int flags);
@@ -1796,6 +1878,9 @@ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
void security_release_secctx(char *secdata, u32 seclen);
+int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
+int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
+int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
#else /* CONFIG_SECURITY */
struct security_mnt_opts {
};
@@ -1818,10 +1903,10 @@ static inline int security_init(void)
return 0;
}
-static inline int security_ptrace_may_access(struct task_struct *child,
+static inline int security_ptrace_access_check(struct task_struct *child,
unsigned int mode)
{
- return cap_ptrace_may_access(child, mode);
+ return cap_ptrace_access_check(child, mode);
}
static inline int security_ptrace_traceme(struct task_struct *parent)
@@ -2266,6 +2351,11 @@ static inline int security_task_create(unsigned long clone_flags)
return 0;
}
+static inline int security_cred_alloc_blank(struct cred *cred, gfp_t gfp)
+{
+ return 0;
+}
+
static inline void security_cred_free(struct cred *cred)
{ }
@@ -2281,6 +2371,11 @@ static inline void security_commit_creds(struct cred *new,
{
}
+static inline void security_transfer_creds(struct cred *new,
+ const struct cred *old)
+{
+}
+
static inline int security_kernel_act_as(struct cred *cred, u32 secid)
{
return 0;
@@ -2292,6 +2387,11 @@ static inline int security_kernel_create_files_as(struct cred *cred,
return 0;
}
+static inline int security_kernel_module_request(void)
+{
+ return 0;
+}
+
static inline int security_task_setuid(uid_t id0, uid_t id1, uid_t id2,
int flags)
{
@@ -2537,6 +2637,19 @@ static inline int security_secctx_to_secid(const char *secdata,
static inline void security_release_secctx(char *secdata, u32 seclen)
{
}
+
+static inline int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
+{
+ return -EOPNOTSUPP;
+}
+static inline int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
+{
+ return -EOPNOTSUPP;
+}
+static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+{
+ return -EOPNOTSUPP;
+}
#endif /* CONFIG_SECURITY */
#ifdef CONFIG_SECURITY_NETWORK
@@ -2575,6 +2688,9 @@ void security_inet_csk_clone(struct sock *newsk,
const struct request_sock *req);
void security_inet_conn_established(struct sock *sk,
struct sk_buff *skb);
+int security_tun_dev_create(void);
+void security_tun_dev_post_create(struct sock *sk);
+int security_tun_dev_attach(struct sock *sk);
#else /* CONFIG_SECURITY_NETWORK */
static inline int security_unix_stream_connect(struct socket *sock,
@@ -2725,6 +2841,20 @@ static inline void security_inet_conn_established(struct sock *sk,
struct sk_buff *skb)
{
}
+
+static inline int security_tun_dev_create(void)
+{
+ return 0;
+}
+
+static inline void security_tun_dev_post_create(struct sock *sk)
+{
+}
+
+static inline int security_tun_dev_attach(struct sock *sk)
+{
+ return 0;
+}
#endif /* CONFIG_SECURITY_NETWORK */
#ifdef CONFIG_SECURITY_NETWORK_XFRM
@@ -2881,6 +3011,9 @@ void security_key_free(struct key *key);
int security_key_permission(key_ref_t key_ref,
const struct cred *cred, key_perm_t perm);
int security_key_getsecurity(struct key *key, char **_buffer);
+int security_key_session_to_parent(const struct cred *cred,
+ const struct cred *parent_cred,
+ struct key *key);
#else
@@ -2908,6 +3041,13 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer)
return 0;
}
+static inline int security_key_session_to_parent(const struct cred *cred,
+ const struct cred *parent_cred,
+ struct key *key)
+{
+ return 0;
+}
+
#endif
#endif /* CONFIG_KEYS */
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index d131e352cfe1..5c84af8c5f6f 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -49,6 +49,7 @@ struct xattr_handler {
ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
+int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
int vfs_removexattr(struct dentry *, const char *);