From 2a7dba391e5628ad665ce84ef9a6648da541ebab Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Tue, 1 Feb 2011 11:05:39 -0500 Subject: fs/vfs/security: pass last path component to LSM on inode creation SELinux would like to implement a new labeling behavior of newly created inodes. We currently label new inodes based on the parent and the creating process. This new behavior would also take into account the name of the new object when deciding the new label. This is not the (supposed) full path, just the last component of the path. This is very useful because creating /etc/shadow is different than creating /etc/passwd but the kernel hooks are unable to differentiate these operations. We currently require that userspace realize it is doing some difficult operation like that and than userspace jumps through SELinux hoops to get things set up correctly. This patch does not implement new behavior, that is obviously contained in a seperate SELinux patch, but it does pass the needed name down to the correct LSM hook. If no such name exists it is fine to pass NULL. Signed-off-by: Eric Paris --- include/linux/security.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index c642bb8b8f5a..05dd5a64aa76 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -315,6 +316,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * then it should return -EOPNOTSUPP to skip this processing. * @inode contains the inode structure of the newly created inode. * @dir contains the inode structure of the parent directory. + * @qstr contains the last path component of the new object * @name will be set to the allocated name suffix (e.g. selinux). * @value will be set to the allocated attribute value. * @len will be set to the length of the value. @@ -1435,7 +1437,8 @@ struct security_operations { int (*inode_alloc_security) (struct inode *inode); void (*inode_free_security) (struct inode *inode); int (*inode_init_security) (struct inode *inode, struct inode *dir, - char **name, void **value, size_t *len); + const struct qstr *qstr, char **name, + void **value, size_t *len); int (*inode_create) (struct inode *dir, struct dentry *dentry, int mode); int (*inode_link) (struct dentry *old_dentry, @@ -1696,7 +1699,8 @@ int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts); int security_inode_alloc(struct inode *inode); void security_inode_free(struct inode *inode); int security_inode_init_security(struct inode *inode, struct inode *dir, - char **name, void **value, size_t *len); + const struct qstr *qstr, char **name, + void **value, size_t *len); int security_inode_create(struct inode *dir, struct dentry *dentry, int mode); int security_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry); @@ -2023,6 +2027,7 @@ static inline void security_inode_free(struct inode *inode) static inline int security_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, char **name, void **value, size_t *len) -- cgit v1.2.3 From 4916ca401e3051dad326ddd69765bd0e3f32fb9b Mon Sep 17 00:00:00 2001 From: Lucian Adrian Grijincu Date: Tue, 1 Feb 2011 18:44:56 +0200 Subject: security: remove unused security_sysctl hook The only user for this hook was selinux. sysctl routes every call through /proc/sys/. Selinux and other security modules use the file system checks for sysctl too, so no need for this hook any more. Signed-off-by: Lucian Adrian Grijincu Signed-off-by: Eric Paris --- include/linux/security.h | 13 ------------- 1 file changed, 13 deletions(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index 05dd5a64aa76..14167f2eb35a 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1259,12 +1259,6 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @cap contains the capability . * @audit: Whether to write an audit message or not * Return 0 if the capability is granted for @tsk. - * @sysctl: - * Check permission before accessing the @table sysctl variable in the - * manner specified by @op. - * @table contains the ctl_table structure for the sysctl variable. - * @op contains the operation (001 = search, 002 = write, 004 = read). - * Return 0 if permission is granted. * @syslog: * Check permission before accessing the kernel message ring or changing * logging to the console. @@ -1385,7 +1379,6 @@ struct security_operations { const kernel_cap_t *permitted); int (*capable) (struct task_struct *tsk, const struct cred *cred, int cap, int audit); - int (*sysctl) (struct ctl_table *table, int op); int (*quotactl) (int cmds, int type, int id, struct super_block *sb); int (*quota_on) (struct dentry *dentry); int (*syslog) (int type); @@ -1668,7 +1661,6 @@ int security_capset(struct cred *new, const struct cred *old, int security_capable(int cap); int security_real_capable(struct task_struct *tsk, int cap); int security_real_capable_noaudit(struct task_struct *tsk, int cap); -int security_sysctl(struct ctl_table *table, int op); int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); @@ -1887,11 +1879,6 @@ int security_real_capable_noaudit(struct task_struct *tsk, int cap) return ret; } -static inline int security_sysctl(struct ctl_table *table, int op) -{ - return 0; -} - static inline int security_quotactl(int cmds, int type, int id, struct super_block *sb) { -- cgit v1.2.3 From 1e6d767924c74929c0cfe839ae8f37bcee9e544e Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Tue, 1 Feb 2011 13:50:58 +0000 Subject: time: Correct the *settime* parameters Both settimeofday() and clock_settime() promise with a 'const' attribute not to alter the arguments passed in. This patch adds the missing 'const' attribute into the various kernel functions implementing these calls. Signed-off-by: Richard Cochran Acked-by: John Stultz LKML-Reference: <20110201134417.545698637@linutronix.de> Signed-off-by: Thomas Gleixner --- include/linux/security.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index c642bb8b8f5a..c096aa6fca60 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_settime(const struct timespec *ts, const struct timezone *tz); 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); @@ -1387,7 +1387,7 @@ struct security_operations { int (*quotactl) (int cmds, int type, int id, struct super_block *sb); int (*quota_on) (struct dentry *dentry); int (*syslog) (int type); - int (*settime) (struct timespec *ts, struct timezone *tz); + int (*settime) (const struct timespec *ts, const struct timezone *tz); int (*vm_enough_memory) (struct mm_struct *mm, long pages); int (*bprm_set_creds) (struct linux_binprm *bprm); @@ -1669,7 +1669,7 @@ int security_sysctl(struct ctl_table *table, int op); int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); -int security_settime(struct timespec *ts, struct timezone *tz); +int security_settime(const struct timespec *ts, const struct timezone *tz); int security_vm_enough_memory(long pages); int security_vm_enough_memory_mm(struct mm_struct *mm, long pages); int security_vm_enough_memory_kern(long pages); @@ -1904,7 +1904,8 @@ static inline int security_syslog(int type) return 0; } -static inline int security_settime(struct timespec *ts, struct timezone *tz) +static inline int security_settime(const struct timespec *ts, + const struct timezone *tz) { return cap_settime(ts, tz); } -- cgit v1.2.3 From e33f770426674a565a188042caf3f974f8b3722d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 22 Feb 2011 18:13:15 -0800 Subject: xfrm: Mark flowi arg to security_xfrm_state_pol_flow_match() const. Signed-off-by: David S. Miller --- include/linux/security.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index b2b7f9749f5e..9b5f184a7f65 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1623,7 +1623,7 @@ struct security_operations { int (*xfrm_policy_lookup) (struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir); int (*xfrm_state_pol_flow_match) (struct xfrm_state *x, struct xfrm_policy *xp, - struct flowi *fl); + const struct flowi *fl); int (*xfrm_decode_session) (struct sk_buff *skb, u32 *secid, int ckall); #endif /* CONFIG_SECURITY_NETWORK_XFRM */ @@ -2761,7 +2761,8 @@ int security_xfrm_state_delete(struct xfrm_state *x); void security_xfrm_state_free(struct xfrm_state *x); int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir); int security_xfrm_state_pol_flow_match(struct xfrm_state *x, - struct xfrm_policy *xp, struct flowi *fl); + struct xfrm_policy *xp, + const struct flowi *fl); int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid); void security_skb_classify_flow(struct sk_buff *skb, struct flowi *fl); @@ -2813,7 +2814,7 @@ static inline int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_s } static inline int security_xfrm_state_pol_flow_match(struct xfrm_state *x, - struct xfrm_policy *xp, struct flowi *fl) + struct xfrm_policy *xp, const struct flowi *fl) { return 1; } -- cgit v1.2.3 From ff36fe2c845cab2102e4826c1ffa0a6ebf487c65 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Thu, 3 Mar 2011 16:09:14 -0500 Subject: LSM: Pass -o remount options to the LSM The VFS mount code passes the mount options to the LSM. The LSM will remove options it understands from the data and the VFS will then pass the remaining options onto the underlying filesystem. This is how options like the SELinux context= work. The problem comes in that -o remount never calls into LSM code. So if you include an LSM specific option it will get passed to the filesystem and will cause the remount to fail. An example of where this is a problem is the 'seclabel' option. The SELinux LSM hook will print this word in /proc/mounts if the filesystem is being labeled using xattrs. If you pass this word on mount it will be silently stripped and ignored. But if you pass this word on remount the LSM never gets called and it will be passed to the FS. The FS doesn't know what seclabel means and thus should fail the mount. For example an ext3 fs mounted over loop # mount -o loop /tmp/fs /mnt/tmp # cat /proc/mounts | grep /mnt/tmp /dev/loop0 /mnt/tmp ext3 rw,seclabel,relatime,errors=continue,barrier=0,data=ordered 0 0 # mount -o remount /mnt/tmp mount: /mnt/tmp not mounted already, or bad option # dmesg EXT3-fs (loop0): error: unrecognized mount option "seclabel" or missing value This patch passes the remount mount options to an new LSM hook. Signed-off-by: Eric Paris Reviewed-by: James Morris --- include/linux/security.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index 14167f2eb35a..d11ac43ecc49 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -268,6 +268,12 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @orig the original mount data copied from userspace. * @copy copied data which will be passed to the security module. * Returns 0 if the copy was successful. + * @sb_remount: + * Extracts security system specifc mount options and verifys no changes + * are being made to those options. + * @sb superblock being remounted + * @data contains the filesystem-specific data. + * Return 0 if permission is granted. * @sb_umount: * Check permission before the @mnt file system is unmounted. * @mnt contains the mounted file system. @@ -1394,6 +1400,7 @@ struct security_operations { int (*sb_alloc_security) (struct super_block *sb); void (*sb_free_security) (struct super_block *sb); int (*sb_copy_data) (char *orig, char *copy); + int (*sb_remount) (struct super_block *sb, void *data); int (*sb_kern_mount) (struct super_block *sb, int flags, void *data); int (*sb_show_options) (struct seq_file *m, struct super_block *sb); int (*sb_statfs) (struct dentry *dentry); @@ -1676,6 +1683,7 @@ int security_bprm_secureexec(struct linux_binprm *bprm); int security_sb_alloc(struct super_block *sb); void security_sb_free(struct super_block *sb); int security_sb_copy_data(char *orig, char *copy); +int security_sb_remount(struct super_block *sb, void *data); int security_sb_kern_mount(struct super_block *sb, int flags, void *data); int security_sb_show_options(struct seq_file *m, struct super_block *sb); int security_sb_statfs(struct dentry *dentry); @@ -1955,6 +1963,11 @@ static inline int security_sb_copy_data(char *orig, char *copy) return 0; } +static inline int security_sb_remount(struct super_block *sb, void *data) +{ + return 0; +} + static inline int security_sb_kern_mount(struct super_block *sb, int flags, void *data) { return 0; -- cgit v1.2.3 From 3486740a4f32a6a466f5ac931654d154790ba648 Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Wed, 23 Mar 2011 16:43:17 -0700 Subject: userns: security: make capabilities relative to the user namespace - Introduce ns_capable to test for a capability in a non-default user namespace. - Teach cap_capable to handle capabilities in a non-default user namespace. The motivation is to get to the unprivileged creation of new namespaces. It looks like this gets us 90% of the way there, with only potential uid confusion issues left. I still need to handle getting all caps after creation but otherwise I think I have a good starter patch that achieves all of your goals. Changelog: 11/05/2010: [serge] add apparmor 12/14/2010: [serge] fix capabilities to created user namespaces Without this, if user serge creates a user_ns, he won't have capabilities to the user_ns he created. THis is because we were first checking whether his effective caps had the caps he needed and returning -EPERM if not, and THEN checking whether he was the creator. Reverse those checks. 12/16/2010: [serge] security_real_capable needs ns argument in !security case 01/11/2011: [serge] add task_ns_capable helper 01/11/2011: [serge] add nsown_capable() helper per Bastian Blank suggestion 02/16/2011: [serge] fix a logic bug: the root user is always creator of init_user_ns, but should not always have capabilities to it! Fix the check in cap_capable(). 02/21/2011: Add the required user_ns parameter to security_capable, fixing a compile failure. 02/23/2011: Convert some macros to functions as per akpm comments. Some couldn't be converted because we can't easily forward-declare them (they are inline if !SECURITY, extern if SECURITY). Add a current_user_ns function so we can use it in capability.h without #including cred.h. Move all forward declarations together to the top of the #ifdef __KERNEL__ section, and use kernel-doc format. 02/23/2011: Per dhowells, clean up comment in cap_capable(). 02/23/2011: Per akpm, remove unreachable 'return -EPERM' in cap_capable. (Original written and signed off by Eric; latest, modified version acked by him) [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: export current_user_ns() for ecryptfs] [serge.hallyn@canonical.com: remove unneeded extra argument in selinux's task_has_capability] Signed-off-by: Eric W. Biederman Signed-off-by: Serge E. Hallyn Acked-by: "Eric W. Biederman" Acked-by: Daniel Lezcano Acked-by: David Howells Cc: James Morris Signed-off-by: Serge E. Hallyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/security.h | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index 56cac520d014..ca02f1716736 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -47,13 +47,14 @@ struct ctl_table; struct audit_krule; +struct user_namespace; /* * These functions are in security/capability.c and are used * as the default capabilities functions */ extern int cap_capable(struct task_struct *tsk, const struct cred *cred, - int cap, int audit); + struct user_namespace *ns, int cap, int audit); extern int cap_settime(const struct timespec *ts, const struct timezone *tz); extern int cap_ptrace_access_check(struct task_struct *child, unsigned int mode); extern int cap_ptrace_traceme(struct task_struct *parent); @@ -1262,6 +1263,7 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * credentials. * @tsk contains the task_struct for the process. * @cred contains the credentials to use. + * @ns contains the user namespace we want the capability in * @cap contains the capability . * @audit: Whether to write an audit message or not * Return 0 if the capability is granted for @tsk. @@ -1384,7 +1386,7 @@ struct security_operations { const kernel_cap_t *inheritable, const kernel_cap_t *permitted); int (*capable) (struct task_struct *tsk, const struct cred *cred, - int cap, int audit); + struct user_namespace *ns, int cap, int audit); int (*quotactl) (int cmds, int type, int id, struct super_block *sb); int (*quota_on) (struct dentry *dentry); int (*syslog) (int type); @@ -1665,9 +1667,12 @@ int security_capset(struct cred *new, const struct cred *old, const kernel_cap_t *effective, const kernel_cap_t *inheritable, const kernel_cap_t *permitted); -int security_capable(const struct cred *cred, int cap); -int security_real_capable(struct task_struct *tsk, int cap); -int security_real_capable_noaudit(struct task_struct *tsk, int cap); +int security_capable(struct user_namespace *ns, const struct cred *cred, + int cap); +int security_real_capable(struct task_struct *tsk, struct user_namespace *ns, + int cap); +int security_real_capable_noaudit(struct task_struct *tsk, + struct user_namespace *ns, int cap); int security_quotactl(int cmds, int type, int id, struct super_block *sb); int security_quota_on(struct dentry *dentry); int security_syslog(int type); @@ -1860,28 +1865,29 @@ static inline int security_capset(struct cred *new, return cap_capset(new, old, effective, inheritable, permitted); } -static inline int security_capable(const struct cred *cred, int cap) +static inline int security_capable(struct user_namespace *ns, + const struct cred *cred, int cap) { - return cap_capable(current, cred, cap, SECURITY_CAP_AUDIT); + return cap_capable(current, cred, ns, cap, SECURITY_CAP_AUDIT); } -static inline int security_real_capable(struct task_struct *tsk, int cap) +static inline int security_real_capable(struct task_struct *tsk, struct user_namespace *ns, int cap) { int ret; rcu_read_lock(); - ret = cap_capable(tsk, __task_cred(tsk), cap, SECURITY_CAP_AUDIT); + ret = cap_capable(tsk, __task_cred(tsk), ns, cap, SECURITY_CAP_AUDIT); rcu_read_unlock(); return ret; } static inline -int security_real_capable_noaudit(struct task_struct *tsk, int cap) +int security_real_capable_noaudit(struct task_struct *tsk, struct user_namespace *ns, int cap) { int ret; rcu_read_lock(); - ret = cap_capable(tsk, __task_cred(tsk), cap, + ret = cap_capable(tsk, __task_cred(tsk), ns, cap, SECURITY_CAP_NOAUDIT); rcu_read_unlock(); return ret; -- cgit v1.2.3 From 8c9e80ed276fc4b9c9fadf29d8bf6b3576112f1a Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Thu, 21 Apr 2011 17:23:19 -0700 Subject: SECURITY: Move exec_permission RCU checks into security modules Right now all RCU walks fall back to reference walk when CONFIG_SECURITY is enabled, even though just the standard capability module is active. This is because security_inode_exec_permission unconditionally fails RCU walks. Move this decision to the low level security module. This requires passing the RCU flags down the security hook. This way at least the capability module and a few easy cases in selinux/smack work with RCU walks with CONFIG_SECURITY=y Signed-off-by: Andi Kleen Acked-by: Eric Paris Signed-off-by: Linus Torvalds --- include/linux/security.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index ca02f1716736..8ce59ef3e5af 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1456,7 +1456,7 @@ struct security_operations { struct inode *new_dir, struct dentry *new_dentry); int (*inode_readlink) (struct dentry *dentry); int (*inode_follow_link) (struct dentry *dentry, struct nameidata *nd); - int (*inode_permission) (struct inode *inode, int mask); + int (*inode_permission) (struct inode *inode, int mask, unsigned flags); int (*inode_setattr) (struct dentry *dentry, struct iattr *attr); int (*inode_getattr) (struct vfsmount *mnt, struct dentry *dentry); int (*inode_setxattr) (struct dentry *dentry, const char *name, -- cgit v1.2.3