From 0f7e4c33eb2c40b1e9cc24d2eab6de5921bc619c Mon Sep 17 00:00:00 2001 From: Kohei Kaigai Date: Thu, 26 May 2011 14:59:25 -0400 Subject: selinux: fix case of names with whitespace/multibytes on /selinux/create I submit the patch again, according to patch submission convension. This patch enables to accept percent-encoded object names as forth argument of /selinux/create interface to avoid possible bugs when we give an object name including whitespace or multibutes. E.g) if and when a userspace object manager tries to create a new object named as "resolve.conf but fake", it shall give this name as the forth argument of the /selinux/create. But sscanf() logic in kernel space fetches only the part earlier than the first whitespace. In this case, selinux may unexpectedly answer a default security context configured to "resolve.conf", but it is bug. Although I could not test this patch on named TYPE_TRANSITION rules actually, But debug printk() message seems to me the logic works correctly. I assume the libselinux provides an interface to apply this logic transparently, so nothing shall not be changed from the viewpoint of application. Signed-off-by: KaiGai Kohei Signed-off-by: Eric Paris --- security/selinux/selinuxfs.c | 37 ++++++++++++++++++++++++++++++++++++- 1 file changed, 36 insertions(+), 1 deletion(-) (limited to 'security') diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index fde4e9d..1948904 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -29,6 +29,7 @@ #include #include #include +#include /* selinuxfs pseudo filesystem for exporting the security policy API. Based on the proc code and the fs/nfsd/nfsctl.c code. */ @@ -751,6 +752,14 @@ out: return length; } +static inline int hexcode_to_int(int code) { + if (code == '\0' || !isxdigit(code)) + return -1; + if (isdigit(code)) + return code - '0'; + return tolower(code) - 'a' + 10; +} + static ssize_t sel_write_create(struct file *file, char *buf, size_t size) { char *scon = NULL, *tcon = NULL; @@ -785,8 +794,34 @@ static ssize_t sel_write_create(struct file *file, char *buf, size_t size) nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf); if (nargs < 3 || nargs > 4) goto out; - if (nargs == 4) + if (nargs == 4) { + /* + * If and when the name of new object to be queried contains + * either whitespace or multibyte characters, they shall be + * encoded based on the percentage-encoding rule. + * If not encoded, the sscanf logic picks up only left-half + * of the supplied name; splitted by a whitespace unexpectedly. + */ + char *r, *w; + int c1, c2; + + r = w = namebuf; + do { + c1 = *r++; + if (c1 == '+') + c1 = ' '; + else if (c1 == '%') { + if ((c1 = hexcode_to_int(*r++)) < 0) + goto out; + if ((c2 = hexcode_to_int(*r++)) < 0) + goto out; + c1 = (c1 << 4) | c2; + } + *w++ = c1; + } while (c1 != '\0'); + objname = namebuf; + } length = security_context_to_sid(scon, strlen(scon) + 1, &ssid); if (length) -- cgit v1.1 From 4e78c724d47e2342aa8fde61f6b8536f662f795f Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Mon, 13 Jun 2011 13:49:11 +0900 Subject: TOMOYO: Fix oops in tomoyo_mount_acl(). In tomoyo_mount_acl() since 2.6.36, kern_path() was called without checking dev_name != NULL. As a result, an unprivileged user can trigger oops by issuing mount(NULL, "/", "ext3", 0, NULL) request. Fix this by checking dev_name != NULL before calling kern_path(dev_name). Signed-off-by: Tetsuo Handa Cc: stable@kernel.org Signed-off-by: James Morris --- security/tomoyo/mount.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'security') diff --git a/security/tomoyo/mount.c b/security/tomoyo/mount.c index 162a864..9fc2e15 100644 --- a/security/tomoyo/mount.c +++ b/security/tomoyo/mount.c @@ -138,7 +138,7 @@ static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name, } if (need_dev) { /* Get mount point or device file. */ - if (kern_path(dev_name, LOOKUP_FOLLOW, &path)) { + if (!dev_name || kern_path(dev_name, LOOKUP_FOLLOW, &path)) { error = -ENOENT; goto out; } -- cgit v1.1 From ded509880f6a0213b09f8ae7bef84acb16eaccbf Mon Sep 17 00:00:00 2001 From: "Roy.Li" Date: Fri, 20 May 2011 10:38:06 +0800 Subject: SELinux: skip file_name_trans_write() when policy downgraded. When policy version is less than POLICYDB_VERSION_FILENAME_TRANS, skip file_name_trans_write(). Signed-off-by: Roy.Li Signed-off-by: Eric Paris --- security/selinux/ss/policydb.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'security') diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 102e9ec..d246aca 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -3222,6 +3222,9 @@ static int filename_trans_write(struct policydb *p, void *fp) __le32 buf[1]; int rc; + if (p->policyvers < POLICYDB_VERSION_FILENAME_TRANS) + return 0; + nel = 0; rc = hashtab_map(p->filename_trans, hashtab_cnt, &nel); if (rc) -- cgit v1.1 From 879669961b11e7f40b518784863a259f735a72bf Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 17 Jun 2011 11:25:59 +0100 Subject: KEYS/DNS: Fix ____call_usermodehelper() to not lose the session keyring ____call_usermodehelper() now erases any credentials set by the subprocess_inf::init() function. The problem is that commit 17f60a7da150 ("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 Acked-by: Eric Paris Tested-by: Jeff Layton Signed-off-by: Linus Torvalds --- security/keys/request_key.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'security') diff --git a/security/keys/request_key.c b/security/keys/request_key.c index d31862e..8e319a4 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -71,9 +71,8 @@ EXPORT_SYMBOL(complete_request_key); * This is called in context of freshly forked kthread before kernel_execve(), * so we can simply install the desired session_keyring at this point. */ -static int umh_keys_init(struct subprocess_info *info) +static int umh_keys_init(struct subprocess_info *info, struct cred *cred) { - struct cred *cred = (struct cred*)current_cred(); struct key *keyring = info->data; return install_session_keyring_to_cred(cred, keyring); -- cgit v1.1 From 482e0cd3dbaa70f2a2bead4b5f2c0d203ef654ba Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 19 Jun 2011 13:01:04 -0400 Subject: devcgroup_inode_permission: take "is it a device node" checks to inlined wrapper inode_permission() calls devcgroup_inode_permission() and almost all such calls are _not_ for device nodes; let's at least keep the common path straight... Signed-off-by: Al Viro --- security/device_cgroup.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) (limited to 'security') diff --git a/security/device_cgroup.c b/security/device_cgroup.c index cd1f779..1be6826 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -474,17 +474,11 @@ struct cgroup_subsys devices_subsys = { .subsys_id = devices_subsys_id, }; -int devcgroup_inode_permission(struct inode *inode, int mask) +int __devcgroup_inode_permission(struct inode *inode, int mask) { struct dev_cgroup *dev_cgroup; struct dev_whitelist_item *wh; - dev_t device = inode->i_rdev; - if (!device) - return 0; - if (!S_ISBLK(inode->i_mode) && !S_ISCHR(inode->i_mode)) - return 0; - rcu_read_lock(); dev_cgroup = task_devcgroup(current); -- cgit v1.1 From b1d7dd80aadb9042e83f9778b484a2f92e0b04d4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 21 Jun 2011 14:32:05 +0100 Subject: KEYS: Fix error handling in construct_key_and_link() Fix error handling in construct_key_and_link(). If construct_alloc_key() returns an error, it shouldn't pass out through the normal path as the key_serial() called by the kleave() statement will oops when it gets an error code in the pointer: BUG: unable to handle kernel paging request at ffffffffffffff84 IP: [] request_key_and_link+0x4d7/0x52f .. Call Trace: [] request_key+0x41/0x75 [] cifs_get_spnego_key+0x206/0x226 [cifs] [] CIFS_SessSetup+0x511/0x1234 [cifs] [] cifs_setup_session+0x90/0x1ae [cifs] [] cifs_get_smb_ses+0x34b/0x40f [cifs] [] cifs_mount+0x13f/0x504 [cifs] [] cifs_do_mount+0xc4/0x672 [cifs] [] mount_fs+0x69/0x155 [] vfs_kern_mount+0x63/0xa0 [] do_kern_mount+0x4d/0xdf [] do_mount+0x63c/0x69f [] sys_mount+0x88/0xc2 [] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells Acked-by: Jeff Layton Signed-off-by: Linus Torvalds --- security/keys/request_key.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'security') diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 8e319a4..8246532 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -469,7 +469,7 @@ static struct key *construct_key_and_link(struct key_type *type, } else if (ret == -EINPROGRESS) { ret = 0; } else { - key = ERR_PTR(ret); + goto couldnt_alloc_key; } key_put(dest_keyring); @@ -479,6 +479,7 @@ static struct key *construct_key_and_link(struct key_type *type, construction_failed: key_negate_and_link(key, key_negative_timeout, NULL, NULL); key_put(key); +couldnt_alloc_key: key_put(dest_keyring); kleave(" = %d", ret); return ERR_PTR(ret); -- cgit v1.1