From d720024e94de4e8b7f10ee83c532926f3ad5d708 Mon Sep 17 00:00:00 2001 From: Michael LeMay Date: Thu, 22 Jun 2006 14:47:17 -0700 Subject: [PATCH] selinux: add hooks for key subsystem Introduce SELinux hooks to support the access key retention subsystem within the kernel. Incorporate new flask headers from a modified version of the SELinux reference policy, with support for the new security class representing retained keys. Extend the "key_alloc" security hook with a task parameter representing the intended ownership context for the key being allocated. Attach security information to root's default keyrings within the SELinux initialization routine. Has passed David's testsuite. Signed-off-by: Michael LeMay Signed-off-by: David Howells Signed-off-by: James Morris Acked-by: Chris Wright Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/dummy.c | 2 +- security/keys/key.c | 8 ++-- security/keys/keyring.c | 5 ++- security/keys/process_keys.c | 15 ++++--- security/keys/request_key.c | 6 ++- security/keys/request_key_auth.c | 2 +- security/selinux/hooks.c | 64 ++++++++++++++++++++++++++++ security/selinux/include/av_perm_to_string.h | 6 +++ security/selinux/include/av_permissions.h | 8 ++++ security/selinux/include/class_to_string.h | 1 + security/selinux/include/flask.h | 1 + security/selinux/include/objsec.h | 5 +++ 12 files changed, 106 insertions(+), 17 deletions(-) (limited to 'security') diff --git a/security/dummy.c b/security/dummy.c index 64f6da0f422..6de4a4a5eb1 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -860,7 +860,7 @@ static int dummy_setprocattr(struct task_struct *p, char *name, void *value, siz } #ifdef CONFIG_KEYS -static inline int dummy_key_alloc(struct key *key) +static inline int dummy_key_alloc(struct key *key, struct task_struct *ctx) { return 0; } diff --git a/security/keys/key.c b/security/keys/key.c index 3fdc49c6a02..14a15abb773 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -247,8 +247,8 @@ static inline void key_alloc_serial(struct key *key) * instantiate the key or discard it before returning */ struct key *key_alloc(struct key_type *type, const char *desc, - uid_t uid, gid_t gid, key_perm_t perm, - int not_in_quota) + uid_t uid, gid_t gid, struct task_struct *ctx, + key_perm_t perm, int not_in_quota) { struct key_user *user = NULL; struct key *key; @@ -318,7 +318,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, #endif /* let the security module know about the key */ - ret = security_key_alloc(key); + ret = security_key_alloc(key, ctx); if (ret < 0) goto security_error; @@ -822,7 +822,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, /* allocate a new key */ key = key_alloc(ktype, description, current->fsuid, current->fsgid, - perm, not_in_quota); + current, perm, not_in_quota); if (IS_ERR(key)) { key_ref = ERR_PTR(PTR_ERR(key)); goto error_3; diff --git a/security/keys/keyring.c b/security/keys/keyring.c index bffa924c1f8..1357207fc9d 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -240,13 +240,14 @@ static long keyring_read(const struct key *keyring, * allocate a keyring and link into the destination keyring */ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, - int not_in_quota, struct key *dest) + struct task_struct *ctx, int not_in_quota, + struct key *dest) { struct key *keyring; int ret; keyring = key_alloc(&key_type_keyring, description, - uid, gid, + uid, gid, ctx, (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL, not_in_quota); diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 217a0bef3c8..a50a91332fe 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -67,7 +67,8 @@ struct key root_session_keyring = { /* * allocate the keyrings to be associated with a UID */ -int alloc_uid_keyring(struct user_struct *user) +int alloc_uid_keyring(struct user_struct *user, + struct task_struct *ctx) { struct key *uid_keyring, *session_keyring; char buf[20]; @@ -76,7 +77,7 @@ int alloc_uid_keyring(struct user_struct *user) /* concoct a default session keyring */ sprintf(buf, "_uid_ses.%u", user->uid); - session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0, NULL); + session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0, NULL); if (IS_ERR(session_keyring)) { ret = PTR_ERR(session_keyring); goto error; @@ -86,7 +87,7 @@ int alloc_uid_keyring(struct user_struct *user) * keyring */ sprintf(buf, "_uid.%u", user->uid); - uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0, + uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0, session_keyring); if (IS_ERR(uid_keyring)) { key_put(session_keyring); @@ -143,7 +144,7 @@ int install_thread_keyring(struct task_struct *tsk) sprintf(buf, "_tid.%u", tsk->pid); - keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL); + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error; @@ -177,7 +178,7 @@ int install_process_keyring(struct task_struct *tsk) if (!tsk->signal->process_keyring) { sprintf(buf, "_pid.%u", tsk->tgid); - keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL); + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error; @@ -217,7 +218,7 @@ static int install_session_keyring(struct task_struct *tsk, if (!keyring) { sprintf(buf, "_ses.%u", tsk->tgid); - keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL); + keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); } @@ -717,7 +718,7 @@ long join_session_keyring(const char *name) keyring = find_keyring_by_name(name, 0); if (PTR_ERR(keyring) == -ENOKEY) { /* not found - try and create a new one */ - keyring = keyring_alloc(name, tsk->uid, tsk->gid, 0, NULL); + keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk, 0, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error2; diff --git a/security/keys/request_key.c b/security/keys/request_key.c index f030a0ccbb9..eab66a06ca5 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -48,7 +48,8 @@ static int call_sbin_request_key(struct key *key, /* allocate a new session keyring */ sprintf(desc, "_req.%u", key->serial); - keyring = keyring_alloc(desc, current->fsuid, current->fsgid, 1, NULL); + keyring = keyring_alloc(desc, current->fsuid, current->fsgid, + current, 1, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error_alloc; @@ -137,7 +138,8 @@ static struct key *__request_key_construction(struct key_type *type, /* create a key and add it to the queue */ key = key_alloc(type, description, - current->fsuid, current->fsgid, KEY_POS_ALL, 0); + current->fsuid, current->fsgid, + current, KEY_POS_ALL, 0); if (IS_ERR(key)) goto alloc_failed; diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index cce6ba6b032..0ecc2e8d2bd 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -148,7 +148,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) sprintf(desc, "%x", target->serial); authkey = key_alloc(&key_type_request_key_auth, desc, - current->fsuid, current->fsgid, + current->fsuid, current->fsgid, current, KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH | KEY_USR_VIEW, 1); if (IS_ERR(authkey)) { diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 54adc9d31e9..524915dfda6 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4252,6 +4252,57 @@ static int selinux_setprocattr(struct task_struct *p, return size; } +#ifdef CONFIG_KEYS + +static int selinux_key_alloc(struct key *k, struct task_struct *tsk) +{ + struct task_security_struct *tsec = tsk->security; + struct key_security_struct *ksec; + + ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); + if (!ksec) + return -ENOMEM; + + ksec->obj = k; + ksec->sid = tsec->sid; + k->security = ksec; + + return 0; +} + +static void selinux_key_free(struct key *k) +{ + struct key_security_struct *ksec = k->security; + + k->security = NULL; + kfree(ksec); +} + +static int selinux_key_permission(key_ref_t key_ref, + struct task_struct *ctx, + key_perm_t perm) +{ + struct key *key; + struct task_security_struct *tsec; + struct key_security_struct *ksec; + + key = key_ref_to_ptr(key_ref); + + tsec = ctx->security; + ksec = key->security; + + /* if no specific permissions are requested, we skip the + permission check. No serious, additional covert channels + appear to be created. */ + if (perm == 0) + return 0; + + return avc_has_perm(tsec->sid, ksec->sid, + SECCLASS_KEY, perm, NULL); +} + +#endif + static struct security_operations selinux_ops = { .ptrace = selinux_ptrace, .capget = selinux_capget, @@ -4406,6 +4457,12 @@ static struct security_operations selinux_ops = { .xfrm_state_delete_security = selinux_xfrm_state_delete, .xfrm_policy_lookup = selinux_xfrm_policy_lookup, #endif + +#ifdef CONFIG_KEYS + .key_alloc = selinux_key_alloc, + .key_free = selinux_key_free, + .key_permission = selinux_key_permission, +#endif }; static __init int selinux_init(void) @@ -4441,6 +4498,13 @@ static __init int selinux_init(void) } else { printk(KERN_INFO "SELinux: Starting in permissive mode\n"); } + +#ifdef CONFIG_KEYS + /* Add security information to initial keyrings */ + security_key_alloc(&root_user_keyring, current); + security_key_alloc(&root_session_keyring, current); +#endif + return 0; } diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h index 70ee65a5881..bc020bde6c8 100644 --- a/security/selinux/include/av_perm_to_string.h +++ b/security/selinux/include/av_perm_to_string.h @@ -242,3 +242,9 @@ S_(SECCLASS_PACKET, PACKET__SEND, "send") S_(SECCLASS_PACKET, PACKET__RECV, "recv") S_(SECCLASS_PACKET, PACKET__RELABELTO, "relabelto") + S_(SECCLASS_KEY, KEY__VIEW, "view") + S_(SECCLASS_KEY, KEY__READ, "read") + S_(SECCLASS_KEY, KEY__WRITE, "write") + S_(SECCLASS_KEY, KEY__SEARCH, "search") + S_(SECCLASS_KEY, KEY__LINK, "link") + S_(SECCLASS_KEY, KEY__SETATTR, "setattr") diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h index 1d9cf3d306b..1205227a3a3 100644 --- a/security/selinux/include/av_permissions.h +++ b/security/selinux/include/av_permissions.h @@ -959,3 +959,11 @@ #define PACKET__SEND 0x00000001UL #define PACKET__RECV 0x00000002UL #define PACKET__RELABELTO 0x00000004UL + +#define KEY__VIEW 0x00000001UL +#define KEY__READ 0x00000002UL +#define KEY__WRITE 0x00000004UL +#define KEY__SEARCH 0x00000008UL +#define KEY__LINK 0x00000010UL +#define KEY__SETATTR 0x00000020UL + diff --git a/security/selinux/include/class_to_string.h b/security/selinux/include/class_to_string.h index 3aec75fee4f..24303b61309 100644 --- a/security/selinux/include/class_to_string.h +++ b/security/selinux/include/class_to_string.h @@ -60,3 +60,4 @@ S_("netlink_kobject_uevent_socket") S_("appletalk_socket") S_("packet") + S_("key") diff --git a/security/selinux/include/flask.h b/security/selinux/include/flask.h index a0eb9e281d1..95887aed2a6 100644 --- a/security/selinux/include/flask.h +++ b/security/selinux/include/flask.h @@ -62,6 +62,7 @@ #define SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET 55 #define SECCLASS_APPLETALK_SOCKET 56 #define SECCLASS_PACKET 57 +#define SECCLASS_KEY 58 /* * Security identifier indices for initial entities diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index 54c03077888..8f5547ad185 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -99,6 +99,11 @@ struct sk_security_struct { u32 peer_sid; /* SID of peer */ }; +struct key_security_struct { + struct key *obj; /* back pointer */ + u32 sid; /* SID of key */ +}; + extern unsigned int selinux_checkreqprot; #endif /* _SELINUX_OBJSEC_H_ */ -- cgit v1.2.3 From 04c567d9313e4927b9835361d8ac0318ce65af6b Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 22 Jun 2006 14:47:18 -0700 Subject: [PATCH] Keys: Fix race between two instantiators of a key Add a revocation notification method to the key type and calls it whilst the key's semaphore is still write-locked after setting the revocation flag. The patch then uses this to maintain a reference on the task_struct of the process that calls request_key() for as long as the authorisation key remains unrevoked. This fixes a potential race between two processes both of which have assumed the authority to instantiate a key (one may have forked the other for example). The problem is that there's no locking around the check for revocation of the auth key and the use of the task_struct it points to, nor does the auth key keep a reference on the task_struct. Access to the "context" pointer in the auth key must thenceforth be done with the auth key semaphore held. The revocation method is called with the target key semaphore held write-locked and the search of the context process's keyrings is done with the auth key semaphore read-locked. The check for the revocation state of the auth key just prior to searching it is done after the auth key is read-locked for the search. This ensures that the auth key can't be revoked between the check and the search. The revocation notification method is added so that the context task_struct can be released as soon as instantiation happens rather than waiting for the auth key to be destroyed, thus avoiding the unnecessary pinning of the requesting process. Signed-off-by: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/keys/key.c | 4 ++++ security/keys/process_keys.c | 42 +++++++++++++++++++++++-------------- security/keys/request_key_auth.c | 45 +++++++++++++++++++++++++++++++++++++++- 3 files changed, 74 insertions(+), 17 deletions(-) (limited to 'security') diff --git a/security/keys/key.c b/security/keys/key.c index 14a15abb773..51f85155738 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -907,6 +907,10 @@ void key_revoke(struct key *key) * it */ down_write(&key->sem); set_bit(KEY_FLAG_REVOKED, &key->flags); + + if (key->type->revoke) + key->type->revoke(key); + up_write(&key->sem); } /* end key_revoke() */ diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index a50a91332fe..4d9825f9962 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -391,6 +391,8 @@ key_ref_t search_process_keyrings(struct key_type *type, struct request_key_auth *rka; key_ref_t key_ref, ret, err; + might_sleep(); + /* we want to return -EAGAIN or -ENOKEY if any of the keyrings were * searchable, but we failed to find a key or we found a negative key; * otherwise we want to return a sample error (probably -EACCES) if @@ -496,27 +498,35 @@ key_ref_t search_process_keyrings(struct key_type *type, */ if (context->request_key_auth && context == current && - type != &key_type_request_key_auth && - key_validate(context->request_key_auth) == 0 + type != &key_type_request_key_auth ) { - rka = context->request_key_auth->payload.data; + /* defend against the auth key being revoked */ + down_read(&context->request_key_auth->sem); - key_ref = search_process_keyrings(type, description, match, - rka->context); + if (key_validate(context->request_key_auth) == 0) { + rka = context->request_key_auth->payload.data; - if (!IS_ERR(key_ref)) - goto found; + key_ref = search_process_keyrings(type, description, + match, rka->context); - switch (PTR_ERR(key_ref)) { - case -EAGAIN: /* no key */ - if (ret) + up_read(&context->request_key_auth->sem); + + if (!IS_ERR(key_ref)) + goto found; + + switch (PTR_ERR(key_ref)) { + case -EAGAIN: /* no key */ + if (ret) + break; + case -ENOKEY: /* negative key */ + ret = key_ref; break; - case -ENOKEY: /* negative key */ - ret = key_ref; - break; - default: - err = key_ref; - break; + default: + err = key_ref; + break; + } + } else { + up_read(&context->request_key_auth->sem); } } diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index 0ecc2e8d2bd..cb9817ced3f 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -20,6 +20,7 @@ static int request_key_auth_instantiate(struct key *, const void *, size_t); static void request_key_auth_describe(const struct key *, struct seq_file *); +static void request_key_auth_revoke(struct key *); static void request_key_auth_destroy(struct key *); static long request_key_auth_read(const struct key *, char __user *, size_t); @@ -31,6 +32,7 @@ struct key_type key_type_request_key_auth = { .def_datalen = sizeof(struct request_key_auth), .instantiate = request_key_auth_instantiate, .describe = request_key_auth_describe, + .revoke = request_key_auth_revoke, .destroy = request_key_auth_destroy, .read = request_key_auth_read, }; @@ -91,6 +93,24 @@ static long request_key_auth_read(const struct key *key, } /* end request_key_auth_read() */ +/*****************************************************************************/ +/* + * handle revocation of an authorisation token key + * - called with the key sem write-locked + */ +static void request_key_auth_revoke(struct key *key) +{ + struct request_key_auth *rka = key->payload.data; + + kenter("{%d}", key->serial); + + if (rka->context) { + put_task_struct(rka->context); + rka->context = NULL; + } + +} /* end request_key_auth_revoke() */ + /*****************************************************************************/ /* * destroy an instantiation authorisation token key @@ -101,6 +121,11 @@ static void request_key_auth_destroy(struct key *key) kenter("{%d}", key->serial); + if (rka->context) { + put_task_struct(rka->context); + rka->context = NULL; + } + key_put(rka->target_key); kfree(rka); @@ -131,14 +156,26 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) * another process */ if (current->request_key_auth) { /* it is - use that instantiation context here too */ + down_read(¤t->request_key_auth->sem); + + /* if the auth key has been revoked, then the key we're + * servicing is already instantiated */ + if (test_bit(KEY_FLAG_REVOKED, + ¤t->request_key_auth->flags)) + goto auth_key_revoked; + irka = current->request_key_auth->payload.data; rka->context = irka->context; rka->pid = irka->pid; + get_task_struct(rka->context); + + up_read(¤t->request_key_auth->sem); } else { /* it isn't - use this process as the context */ rka->context = current; rka->pid = current->pid; + get_task_struct(rka->context); } rka->target_key = key_get(target); @@ -161,9 +198,15 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info) if (ret < 0) goto error_inst; - kleave(" = {%d})", authkey->serial); + kleave(" = {%d}", authkey->serial); return authkey; +auth_key_revoked: + up_read(¤t->request_key_auth->sem); + kfree(rka); + kleave("= -EKEYREVOKED"); + return ERR_PTR(-EKEYREVOKED); + error_inst: key_revoke(authkey); key_put(authkey); -- cgit v1.2.3 From 454e2398be9b9fa30433fccc548db34d19aa9958 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 23 Jun 2006 02:02:57 -0700 Subject: [PATCH] VFS: Permit filesystem to override root dentry on mount Extend the get_sb() filesystem operation to take an extra argument that permits the VFS to pass in the target vfsmount that defines the mountpoint. The filesystem is then required to manually set the superblock and root dentry pointers. For most filesystems, this should be done with simple_set_mnt() which will set the superblock pointer and then set the root dentry to the superblock's s_root (as per the old default behaviour). The get_sb() op now returns an integer as there's now no need to return the superblock pointer. This patch permits a superblock to be implicitly shared amongst several mount points, such as can be done with NFS to avoid potential inode aliasing. In such a case, simple_set_mnt() would not be called, and instead the mnt_root and mnt_sb would be set directly. The patch also makes the following changes: (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount pointer argument and return an integer, so most filesystems have to change very little. (*) If one of the convenience function is not used, then get_sb() should normally call simple_set_mnt() to instantiate the vfsmount. This will always return 0, and so can be tail-called from get_sb(). (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the dcache upon superblock destruction rather than shrink_dcache_anon(). This is required because the superblock may now have multiple trees that aren't actually bound to s_root, but that still need to be cleaned up. The currently called functions assume that the whole tree is rooted at s_root, and that anonymous dentries are not the roots of trees which results in dentries being left unculled. However, with the way NFS superblock sharing are currently set to be implemented, these assumptions are violated: the root of the filesystem is simply a dummy dentry and inode (the real inode for '/' may well be inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries with child trees. [*] Anonymous until discovered from another tree. (*) The documentation has been adjusted, including the additional bit of changing ext2_* into foo_* in the documentation. [akpm@osdl.org: convert ipath_fs, do other stuff] Signed-off-by: David Howells Acked-by: Al Viro Cc: Nathan Scott Cc: Roland Dreier Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/inode.c | 8 ++++---- security/selinux/selinuxfs.c | 7 ++++--- 2 files changed, 8 insertions(+), 7 deletions(-) (limited to 'security') diff --git a/security/inode.c b/security/inode.c index 0f77b022366..e6fc29ac856 100644 --- a/security/inode.c +++ b/security/inode.c @@ -135,11 +135,11 @@ static int fill_super(struct super_block *sb, void *data, int silent) return simple_fill_super(sb, SECURITYFS_MAGIC, files); } -static struct super_block *get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data) +static int get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, + void *data, struct vfsmount *mnt) { - return get_sb_single(fs_type, flags, data, fill_super); + return get_sb_single(fs_type, flags, data, fill_super, mnt); } static struct file_system_type fs_type = { diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 2e73d3279f2..7029bbc9bef 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -1345,10 +1345,11 @@ err: goto out; } -static struct super_block *sel_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) +static int sel_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data, + struct vfsmount *mnt) { - return get_sb_single(fs_type, flags, data, sel_fill_super); + return get_sb_single(fs_type, flags, data, sel_fill_super, mnt); } static struct file_system_type sel_fs_type = { -- cgit v1.2.3 From 726c334223180e3c0197cc980a432681370d4baf Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 23 Jun 2006 02:02:58 -0700 Subject: [PATCH] VFS: Permit filesystem to perform statfs with a known root dentry Give the statfs superblock operation a dentry pointer rather than a superblock pointer. This complements the get_sb() patch. That reduced the significance of sb->s_root, allowing NFS to place a fake root there. However, NFS does require a dentry to use as a target for the statfs operation. This permits the root in the vfsmount to be used instead. linux/mount.h has been added where necessary to make allyesconfig build successfully. Interest has also been expressed for use with the FUSE and XFS filesystems. Signed-off-by: David Howells Acked-by: Al Viro Cc: Nathan Scott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/dummy.c | 2 +- security/selinux/hooks.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'security') diff --git a/security/dummy.c b/security/dummy.c index 6de4a4a5eb1..c98d553984e 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -191,7 +191,7 @@ static int dummy_sb_kern_mount (struct super_block *sb, void *data) return 0; } -static int dummy_sb_statfs (struct super_block *sb) +static int dummy_sb_statfs (struct dentry *dentry) { return 0; } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 524915dfda6..093efba4d9b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1903,13 +1903,13 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data) return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); } -static int selinux_sb_statfs(struct super_block *sb) +static int selinux_sb_statfs(struct dentry *dentry) { struct avc_audit_data ad; AVC_AUDIT_DATA_INIT(&ad,FS); - ad.u.fs.dentry = sb->s_root; - return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); + ad.u.fs.dentry = dentry->d_sb->s_root; + return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); } static int selinux_mount(char * dev_name, -- cgit v1.2.3 From 03e68060636e05989ea94bcb671ab633948f328c Mon Sep 17 00:00:00 2001 From: James Morris Date: Fri, 23 Jun 2006 02:03:58 -0700 Subject: [PATCH] lsm: add task_setioprio hook Implement an LSM hook for setting a task's IO priority, similar to the hook for setting a tasks's nice value. A previous version of this LSM hook was included in an older version of multiadm by Jan Engelhardt, although I don't recall it being submitted upstream. Also included is the corresponding SELinux hook, which re-uses the setsched permission in the proccess class. Signed-off-by: James Morris Acked-by: Stephen Smalley Cc: Jan Engelhardt Cc: Chris Wright Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/dummy.c | 6 ++++++ security/selinux/hooks.c | 6 ++++++ 2 files changed, 12 insertions(+) (limited to 'security') diff --git a/security/dummy.c b/security/dummy.c index c98d553984e..879a98523b1 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -516,6 +516,11 @@ static int dummy_task_setnice (struct task_struct *p, int nice) return 0; } +static int dummy_task_setioprio (struct task_struct *p, int ioprio) +{ + return 0; +} + static int dummy_task_setrlimit (unsigned int resource, struct rlimit *new_rlim) { return 0; @@ -972,6 +977,7 @@ void security_fixup_ops (struct security_operations *ops) set_to_dummy_if_null(ops, task_getsid); set_to_dummy_if_null(ops, task_setgroups); set_to_dummy_if_null(ops, task_setnice); + set_to_dummy_if_null(ops, task_setioprio); set_to_dummy_if_null(ops, task_setrlimit); set_to_dummy_if_null(ops, task_setscheduler); set_to_dummy_if_null(ops, task_getscheduler); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 093efba4d9b..9dcf298921d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2645,6 +2645,11 @@ static int selinux_task_setnice(struct task_struct *p, int nice) return task_has_perm(current,p, PROCESS__SETSCHED); } +static int selinux_task_setioprio(struct task_struct *p, int ioprio) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) { struct rlimit *old_rlim = current->signal->rlim + resource; @@ -4383,6 +4388,7 @@ static struct security_operations selinux_ops = { .task_getsid = selinux_task_getsid, .task_setgroups = selinux_task_setgroups, .task_setnice = selinux_task_setnice, + .task_setioprio = selinux_task_setioprio, .task_setrlimit = selinux_task_setrlimit, .task_setscheduler = selinux_task_setscheduler, .task_getscheduler = selinux_task_getscheduler, -- cgit v1.2.3 From 35601547baf92d984b6e59cf3583649da04baea5 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Fri, 23 Jun 2006 02:04:01 -0700 Subject: [PATCH] SELinux: add task_movememory hook This patch adds new security hook, task_movememory, to be called when memory owened by a task is to be moved (e.g. when migrating pages to a this hook is identical to the setscheduler implementation, but a separate hook introduced to allow this check to be specialized in the future if necessary. Since the last posting, the hook has been renamed following feedback from Christoph Lameter. Signed-off-by: David Quigley Acked-by: Stephen Smalley Signed-off-by: James Morris Cc: Christoph Lameter Cc: Andi Kleen Acked-by: Chris Wright Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/dummy.c | 6 ++++++ security/selinux/hooks.c | 6 ++++++ 2 files changed, 12 insertions(+) (limited to 'security') diff --git a/security/dummy.c b/security/dummy.c index 879a98523b1..c3c5493581e 100644 --- a/security/dummy.c +++ b/security/dummy.c @@ -537,6 +537,11 @@ static int dummy_task_getscheduler (struct task_struct *p) return 0; } +static int dummy_task_movememory (struct task_struct *p) +{ + return 0; +} + static int dummy_task_wait (struct task_struct *p) { return 0; @@ -981,6 +986,7 @@ void security_fixup_ops (struct security_operations *ops) set_to_dummy_if_null(ops, task_setrlimit); set_to_dummy_if_null(ops, task_setscheduler); set_to_dummy_if_null(ops, task_getscheduler); + set_to_dummy_if_null(ops, task_movememory); set_to_dummy_if_null(ops, task_wait); set_to_dummy_if_null(ops, task_kill); set_to_dummy_if_null(ops, task_prctl); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9dcf298921d..79c16e31c88 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2679,6 +2679,11 @@ static int selinux_task_getscheduler(struct task_struct *p) return task_has_perm(current, p, PROCESS__GETSCHED); } +static int selinux_task_movememory(struct task_struct *p) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) { u32 perm; @@ -4392,6 +4397,7 @@ static struct security_operations selinux_ops = { .task_setrlimit = selinux_task_setrlimit, .task_setscheduler = selinux_task_setscheduler, .task_getscheduler = selinux_task_getscheduler, + .task_movememory = selinux_task_movememory, .task_kill = selinux_task_kill, .task_wait = selinux_task_wait, .task_prctl = selinux_task_prctl, -- cgit v1.2.3