forked from luck/tmp_suning_uos_patched
879669961b
____call_usermodehelper() now erases any credentials set by the
subprocess_inf::init() function. The problem is that commit
17f60a7da1 ("capabilites: allow the application of capability limits
to usermode helpers") creates and commits new credentials with
prepare_kernel_cred() after the call to the init() function. This wipes
all keyrings after umh_keys_init() is called.
The best way to deal with this is to put the init() call just prior to
the commit_creds() call, and pass the cred pointer to init(). That
means that umh_keys_init() and suchlike can modify the credentials
_before_ they are published and potentially in use by the rest of the
system.
This prevents request_key() from working as it is prevented from passing
the session keyring it set up with the authorisation token to
/sbin/request-key, and so the latter can't assume the authority to
instantiate the key. This causes the in-kernel DNS resolver to fail
with ENOKEY unconditionally.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
122 lines
3.8 KiB
C
122 lines
3.8 KiB
C
#ifndef __LINUX_KMOD_H__
|
|
#define __LINUX_KMOD_H__
|
|
|
|
/*
|
|
* include/linux/kmod.h
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/sysctl.h>
|
|
|
|
#define KMOD_PATH_LEN 256
|
|
|
|
#ifdef CONFIG_MODULES
|
|
extern char modprobe_path[]; /* for sysctl */
|
|
/* modprobe exit status on success, -ve on error. Return value
|
|
* usually useless though. */
|
|
extern int __request_module(bool wait, const char *name, ...) \
|
|
__attribute__((format(printf, 2, 3)));
|
|
#define request_module(mod...) __request_module(true, mod)
|
|
#define request_module_nowait(mod...) __request_module(false, mod)
|
|
#define try_then_request_module(x, mod...) \
|
|
((x) ?: (__request_module(true, mod), (x)))
|
|
#else
|
|
static inline int request_module(const char *name, ...) { return -ENOSYS; }
|
|
static inline int request_module_nowait(const char *name, ...) { return -ENOSYS; }
|
|
#define try_then_request_module(x, mod...) (x)
|
|
#endif
|
|
|
|
|
|
struct cred;
|
|
struct file;
|
|
|
|
enum umh_wait {
|
|
UMH_NO_WAIT = -1, /* don't wait at all */
|
|
UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
|
|
UMH_WAIT_PROC = 1, /* wait for the process to complete */
|
|
};
|
|
|
|
struct subprocess_info {
|
|
struct work_struct work;
|
|
struct completion *complete;
|
|
char *path;
|
|
char **argv;
|
|
char **envp;
|
|
enum umh_wait wait;
|
|
int retval;
|
|
int (*init)(struct subprocess_info *info, struct cred *new);
|
|
void (*cleanup)(struct subprocess_info *info);
|
|
void *data;
|
|
};
|
|
|
|
/* Allocate a subprocess_info structure */
|
|
struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
|
|
char **envp, gfp_t gfp_mask);
|
|
|
|
/* Set various pieces of state into the subprocess_info structure */
|
|
void call_usermodehelper_setfns(struct subprocess_info *info,
|
|
int (*init)(struct subprocess_info *info, struct cred *new),
|
|
void (*cleanup)(struct subprocess_info *info),
|
|
void *data);
|
|
|
|
/* Actually execute the sub-process */
|
|
int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
|
|
|
|
/* Free the subprocess_info. This is only needed if you're not going
|
|
to call call_usermodehelper_exec */
|
|
void call_usermodehelper_freeinfo(struct subprocess_info *info);
|
|
|
|
static inline int
|
|
call_usermodehelper_fns(char *path, char **argv, char **envp,
|
|
enum umh_wait wait,
|
|
int (*init)(struct subprocess_info *info, struct cred *new),
|
|
void (*cleanup)(struct subprocess_info *), void *data)
|
|
{
|
|
struct subprocess_info *info;
|
|
gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
|
|
|
|
info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
|
|
|
|
if (info == NULL)
|
|
return -ENOMEM;
|
|
|
|
call_usermodehelper_setfns(info, init, cleanup, data);
|
|
|
|
return call_usermodehelper_exec(info, wait);
|
|
}
|
|
|
|
static inline int
|
|
call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
|
|
{
|
|
return call_usermodehelper_fns(path, argv, envp, wait,
|
|
NULL, NULL, NULL);
|
|
}
|
|
|
|
extern struct ctl_table usermodehelper_table[];
|
|
|
|
extern void usermodehelper_init(void);
|
|
|
|
extern int usermodehelper_disable(void);
|
|
extern void usermodehelper_enable(void);
|
|
extern bool usermodehelper_is_disabled(void);
|
|
|
|
#endif /* __LINUX_KMOD_H__ */
|