diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2010-05-26 14:43:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-27 09:12:45 -0700 |
| commit | 685bfd2c48bb3284d31e73ff3151c957d76deda9 (patch) | |
| tree | 177210787515f48c0eaad5216bd012f4a2fb2149 /security | |
| parent | 898b374af6f71041bd3bceebe257e564f3f1d458 (diff) | |
umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init()
call_usermodehelper_keys() uses call_usermodehelper_setkeys() to change
subprocess_info->cred in advance. Now that we have info->init() we can
change this code to set tgcred->session_keyring in context of execing
kernel thread.
Note: since currently call_usermodehelper_keys() is never called with
UMH_NO_WAIT, call_usermodehelper_keys()->key_get() and umh_keys_cleanup()
are not really needed, we could rely on install_session_keyring_to_cred()
which does key_get() on success.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'security')
| -rw-r--r-- | security/keys/internal.h | 1 | ||||
| -rw-r--r-- | security/keys/process_keys.c | 3 | ||||
| -rw-r--r-- | security/keys/request_key.c | 32 |
3 files changed, 34 insertions, 2 deletions
diff --git a/security/keys/internal.h b/security/keys/internal.h index 5d4402a1161a..38783dcf6c61 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -124,6 +124,7 @@ extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); extern int install_user_keyrings(void); extern int install_thread_keyring_to_cred(struct cred *); extern int install_process_keyring_to_cred(struct cred *); +extern int install_session_keyring_to_cred(struct cred *, struct key *); extern struct key *request_key_and_link(struct key_type *type, const char *description, diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 20a38fed61b1..6b8e4ff4cc68 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -216,8 +216,7 @@ static int install_process_keyring(void) /* * install a session keyring directly to a credentials struct */ -static int install_session_keyring_to_cred(struct cred *cred, - struct key *keyring) +int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) { unsigned long flags; struct key *old; diff --git a/security/keys/request_key.c b/security/keys/request_key.c index f656e9c069e3..f5ec9ac5d57c 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -58,6 +58,38 @@ void complete_request_key(struct key_construction *cons, int error) } EXPORT_SYMBOL(complete_request_key); +static int umh_keys_init(struct subprocess_info *info) +{ + struct cred *cred = (struct cred*)current_cred(); + struct key *keyring = info->data; + /* + * This is called in context of freshly forked kthread before + * kernel_execve(), we can just change our ->session_keyring. + */ + return install_session_keyring_to_cred(cred, keyring); +} + +static void umh_keys_cleanup(struct subprocess_info *info) +{ + struct key *keyring = info->data; + key_put(keyring); +} + +static int call_usermodehelper_keys(char *path, char **argv, char **envp, + struct key *session_keyring, enum umh_wait wait) +{ + gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL; + struct subprocess_info *info = + call_usermodehelper_setup(path, argv, envp, gfp_mask); + + if (!info) + return -ENOMEM; + + call_usermodehelper_setfns(info, umh_keys_init, umh_keys_cleanup, + key_get(session_keyring)); + return call_usermodehelper_exec(info, wait); +} + /* * request userspace finish the construction of a key * - execute "/sbin/request-key <op> <key> <uid> <gid> <keyring> <keyring> <keyring>" |