From 002345925e6c45861f60db6f4fc6236713fd8847 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Feb 2010 15:36:43 -0800 Subject: syslog: distinguish between /proc/kmsg and syscalls This allows the LSM to distinguish between syslog functions originating from /proc/kmsg access and direct syscalls. By default, the commoncaps will now no longer require CAP_SYS_ADMIN to read an opened /proc/kmsg file descriptor. For example the kernel syslog reader can now drop privileges after opening /proc/kmsg, instead of staying privileged with CAP_SYS_ADMIN. MAC systems that implement security_syslog have unchanged behavior. Signed-off-by: Kees Cook Acked-by: Serge Hallyn Acked-by: John Johansen Signed-off-by: James Morris --- security/selinux/hooks.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9a2ee845e9d4..a4862a0730fa 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -76,6 +76,7 @@ #include #include #include +#include #include "avc.h" #include "objsec.h" @@ -2049,11 +2050,11 @@ static int selinux_quota_on(struct dentry *dentry) return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); } -static int selinux_syslog(int type) +static int selinux_syslog(int type, bool from_file) { int rc; - rc = cap_syslog(type); + rc = cap_syslog(type, from_file); if (rc) return rc; -- cgit v1.2.3 From d78ca3cd733d8a2c3dcd88471beb1a15d973eed8 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Feb 2010 15:37:13 -0800 Subject: syslog: use defined constants instead of raw numbers Right now the syslog "type" action are just raw numbers which makes the source difficult to follow. This patch replaces the raw numbers with defined constants for some level of sanity. Signed-off-by: Kees Cook Acked-by: John Johansen Acked-by: Serge Hallyn Signed-off-by: James Morris --- security/selinux/hooks.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a4862a0730fa..6b36ce2eef2e 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2059,20 +2059,21 @@ static int selinux_syslog(int type, bool from_file) return rc; switch (type) { - case 3: /* Read last kernel messages */ - case 10: /* Return size of the log buffer */ + case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ + case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ rc = task_has_system(current, SYSTEM__SYSLOG_READ); break; - case 6: /* Disable logging to console */ - case 7: /* Enable logging to console */ - case 8: /* Set level of messages printed to console */ + case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ + case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ + /* Set level of messages printed to console */ + case SYSLOG_ACTION_CONSOLE_LEVEL: rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); break; - case 0: /* Close log */ - case 1: /* Open log */ - case 2: /* Read from log */ - case 4: /* Read/clear last kernel messages */ - case 5: /* Clear ring buffer */ + case SYSLOG_ACTION_CLOSE: /* Close log */ + case SYSLOG_ACTION_OPEN: /* Open log */ + case SYSLOG_ACTION_READ: /* Read from log */ + case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ + case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ default: rc = task_has_system(current, SYSTEM__SYSLOG_MOD); break; -- cgit v1.2.3 From 189b3b1c89761054fee3438f063d7f257306e2d8 Mon Sep 17 00:00:00 2001 From: "wzt.wzt@gmail.com" Date: Tue, 23 Feb 2010 23:15:28 +0800 Subject: Security: add static to security_ops and default_security_ops variable Enhance the security framework to support resetting the active security module. This eliminates the need for direct use of the security_ops and default_security_ops variables outside of security.c, so make security_ops and default_security_ops static. Also remove the secondary_ops variable as a cleanup since there is no use for that. secondary_ops was originally used by SELinux to call the "secondary" security module (capability or dummy), but that was replaced by direct calls to capability and the only remaining use is to save and restore the original security ops pointer value if SELinux is disabled by early userspace based on /etc/selinux/config. Further, if we support this directly in the security framework, then we can just use &default_security_ops for this purpose since that is now available. Signed-off-by: Zhitong Wang Acked-by: Stephen Smalley Signed-off-by: James Morris --- security/selinux/hooks.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 6b36ce2eef2e..dc7660074b99 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -126,13 +126,6 @@ __setup("selinux=", selinux_enabled_setup); int selinux_enabled = 1; #endif - -/* - * Minimal support for a secondary security module, - * just to allow the use of the capability module. - */ -static struct security_operations *secondary_ops; - /* Lists of inode and superblock security structures initialized before the policy was loaded. */ static LIST_HEAD(superblock_security_head); @@ -5674,9 +5667,6 @@ static __init int selinux_init(void) 0, SLAB_PANIC, NULL); avc_init(); - secondary_ops = security_ops; - if (!secondary_ops) - panic("SELinux: No initial security operations\n"); if (register_security(&selinux_ops)) panic("SELinux: Unable to register with kernel.\n"); @@ -5837,8 +5827,7 @@ int selinux_disable(void) selinux_disabled = 1; selinux_enabled = 0; - /* Reset security_ops to the secondary module, dummy or capability. */ - security_ops = secondary_ops; + reset_security_ops(); /* Try to destroy the avc node cache */ avc_disable(); -- cgit v1.2.3 From ef57471a73b67a7b65fd8708fd55c77cb7c619af Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 26 Feb 2010 01:56:16 +0000 Subject: SELinux: Make selinux_kernel_create_files_as() shouldn't just always return 0 Make selinux_kernel_create_files_as() return an error when it gets one, rather than unconditionally returning 0. Without this, cachefiles doesn't return an error if the SELinux policy doesn't let it create files with the label of the directory at the base of the cache. Signed-off-by: David Howells Signed-off-by: James Morris --- security/selinux/hooks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index dc7660074b99..5feecb41009d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3329,7 +3329,7 @@ static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) if (ret == 0) tsec->create_sid = isec->sid; - return 0; + return ret; } static int selinux_kernel_module_request(char *kmod_name) -- cgit v1.2.3