From 12b3052c3ee8f508b2c7ee4ddd63ed03423409d8 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Mon, 15 Nov 2010 18:36:29 -0500 Subject: capabilities/syslog: open code cap_syslog logic to fix build failure The addition of CONFIG_SECURITY_DMESG_RESTRICT resulted in a build failure when CONFIG_PRINTK=n. This is because the capabilities code which used the new option was built even though the variable in question didn't exist. The patch here fixes this by moving the capabilities checks out of the LSM and into the caller. All (known) LSMs should have been calling the capabilities hook already so it actually makes the code organization better to eliminate the hook altogether. Signed-off-by: Eric Paris Acked-by: James Morris Signed-off-by: Linus Torvalds --- security/capability.c | 5 +++++ security/commoncap.c | 21 --------------------- security/security.c | 4 ++-- security/selinux/hooks.c | 6 +----- security/smack/smack_lsm.c | 8 ++------ 5 files changed, 10 insertions(+), 34 deletions(-) (limited to 'security') diff --git a/security/capability.c b/security/capability.c index 30ae00fbecd5..c773635ca3a0 100644 --- a/security/capability.c +++ b/security/capability.c @@ -17,6 +17,11 @@ static int cap_sysctl(ctl_table *table, int op) return 0; } +static int cap_syslog(int type) +{ + return 0; +} + static int cap_quotactl(int cmds, int type, int id, struct super_block *sb) { return 0; diff --git a/security/commoncap.c b/security/commoncap.c index 04b80f9912bf..64c2ed9c9015 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -27,7 +27,6 @@ #include #include #include -#include /* * If a non-root user executes a setuid-root binary in @@ -883,26 +882,6 @@ error: return error; } -/** - * cap_syslog - Determine whether syslog function is permitted - * @type: Function requested - * @from_file: Whether this request came from an open file (i.e. /proc) - * - * Determine whether the current process is permitted to use a particular - * syslog function, returning 0 if permission is granted, -ve if not. - */ -int cap_syslog(int type, bool from_file) -{ - if (type != SYSLOG_ACTION_OPEN && from_file) - return 0; - if (dmesg_restrict && !capable(CAP_SYS_ADMIN)) - return -EPERM; - if ((type != SYSLOG_ACTION_READ_ALL && - type != SYSLOG_ACTION_SIZE_BUFFER) && !capable(CAP_SYS_ADMIN)) - return -EPERM; - return 0; -} - /** * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted * @mm: The VM space in which the new mapping is to be made diff --git a/security/security.c b/security/security.c index 3ef5e2a7a741..1b798d3df710 100644 --- a/security/security.c +++ b/security/security.c @@ -197,9 +197,9 @@ int security_quota_on(struct dentry *dentry) return security_ops->quota_on(dentry); } -int security_syslog(int type, bool from_file) +int security_syslog(int type) { - return security_ops->syslog(type, from_file); + return security_ops->syslog(type); } int security_settime(struct timespec *ts, struct timezone *tz) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index d9154cf90ae1..65fa8bf596f5 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1973,14 +1973,10 @@ static int selinux_quota_on(struct dentry *dentry) return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); } -static int selinux_syslog(int type, bool from_file) +static int selinux_syslog(int type) { int rc; - rc = cap_syslog(type, from_file); - if (rc) - return rc; - switch (type) { case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index bc39f4067af6..489a85afa477 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -157,15 +157,11 @@ static int smack_ptrace_traceme(struct task_struct *ptp) * * Returns 0 on success, error code otherwise. */ -static int smack_syslog(int type, bool from_file) +static int smack_syslog(int typefrom_file) { - int rc; + int rc = 0; char *sp = current_security(); - rc = cap_syslog(type, from_file); - if (rc != 0) - return rc; - if (capable(CAP_MAC_OVERRIDE)) return 0; -- cgit v1.2.1 From 3fc5e98d8cf85e0d77fc597b49e9268dff67400e Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 22 Dec 2010 16:24:13 +0000 Subject: KEYS: Don't call up_write() if __key_link_begin() returns an error In construct_alloc_key(), up_write() is called in the error path if __key_link_begin() fails, but this is incorrect as __key_link_begin() only returns with the nominated keyring locked if it returns successfully. Without this patch, you might see the following in dmesg: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- mount.cifs/5769 is trying to release lock (&key->sem) at: [] request_key_and_link+0x263/0x3fc but there are no more locks to release! other info that might help us debug this: 3 locks held by mount.cifs/5769: #0: (&type->s_umount_key#41/1){+.+.+.}, at: [] sget+0x278/0x3e7 #1: (&ret_buf->session_mutex){+.+.+.}, at: [] cifs_get_smb_ses+0x35a/0x443 [cifs] #2: (root_key_user.cons_lock){+.+.+.}, at: [] request_key_and_link+0x10a/0x3fc stack backtrace: Pid: 5769, comm: mount.cifs Not tainted 2.6.37-rc6+ #1 Call Trace: [] ? request_key_and_link+0x263/0x3fc [] print_unlock_inbalance_bug+0xca/0xd5 [] lock_release_non_nested+0xc1/0x263 [] ? request_key_and_link+0x263/0x3fc [] ? request_key_and_link+0x263/0x3fc [] lock_release+0x17d/0x1a4 [] up_write+0x23/0x3b [] request_key_and_link+0x263/0x3fc [] ? cifs_get_spnego_key+0x61/0x21f [cifs] [] request_key+0x41/0x74 [] cifs_get_spnego_key+0x200/0x21f [cifs] [] CIFS_SessSetup+0x55d/0x1273 [cifs] [] cifs_setup_session+0x90/0x1ae [cifs] [] cifs_get_smb_ses+0x37f/0x443 [cifs] [] cifs_mount+0x1aa1/0x23f3 [cifs] [] ? alloc_debug_processing+0xdb/0x120 [] ? cifs_get_spnego_key+0x1ef/0x21f [cifs] [] cifs_do_mount+0x165/0x2b3 [cifs] [] vfs_kern_mount+0xaf/0x1dc [] do_kern_mount+0x4d/0xef [] do_mount+0x6f4/0x733 [] sys_mount+0x88/0xc2 [] system_call_fastpath+0x16/0x1b Reported-by: Jeff Layton Signed-off-by: David Howells Reviewed-and-Tested-by: Jeff Layton Signed-off-by: Linus Torvalds --- security/keys/request_key.c | 1 - 1 file changed, 1 deletion(-) (limited to 'security') diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 0088dd8bf68a..0ea52d25a6bd 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -403,7 +403,6 @@ link_check_failed: return ret; link_prealloc_failed: - up_write(&dest_keyring->sem); mutex_unlock(&user->cons_lock); kleave(" = %d [prelink]", ret); return ret; -- cgit v1.2.1