diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-21 13:25:04 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-21 13:25:04 -0700 |
commit | 3556485f1595e3964ba539e39ea682acbb835cee (patch) | |
tree | 7f5ee254f425b1427ac0059b5f347a307f8538a1 | |
parent | b8716614a7cc2fc15ea2a518edd04755fb08d922 (diff) | |
parent | 09f61cdbb32a9d812c618d3922db533542736bb0 (diff) |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates for 3.4 from James Morris:
"The main addition here is the new Yama security module from Kees Cook,
which was discussed at the Linux Security Summit last year. Its
purpose is to collect miscellaneous DAC security enhancements in one
place. This also marks a departure in policy for LSM modules, which
were previously limited to being standalone access control systems.
Chromium OS is using Yama, and I believe there are plans for Ubuntu,
at least.
This patchset also includes maintenance updates for AppArmor, TOMOYO
and others."
Fix trivial conflict in <net/sock.h> due to the jumo_label->static_key
rename.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (38 commits)
AppArmor: Fix location of const qualifier on generated string tables
TOMOYO: Return error if fails to delete a domain
AppArmor: add const qualifiers to string arrays
AppArmor: Add ability to load extended policy
TOMOYO: Return appropriate value to poll().
AppArmor: Move path failure information into aa_get_name and rename
AppArmor: Update dfa matching routines.
AppArmor: Minor cleanup of d_namespace_path to consolidate error handling
AppArmor: Retrieve the dentry_path for error reporting when path lookup fails
AppArmor: Add const qualifiers to generated string tables
AppArmor: Fix oops in policy unpack auditing
AppArmor: Fix error returned when a path lookup is disconnected
KEYS: testing wrong bit for KEY_FLAG_REVOKED
TOMOYO: Fix mount flags checking order.
security: fix ima kconfig warning
AppArmor: Fix the error case for chroot relative path name lookup
AppArmor: fix mapping of META_READ to audit and quiet flags
AppArmor: Fix underflow in xindex calculation
AppArmor: Fix dropping of allowed operations that are force audited
AppArmor: Add mising end of structure test to caps unpacking
...
71 files changed, 1034 insertions, 250 deletions
diff --git a/Documentation/networking/dns_resolver.txt b/Documentation/networking/dns_resolver.txt index 7f531ad83285..d86adcdae420 100644 --- a/Documentation/networking/dns_resolver.txt +++ b/Documentation/networking/dns_resolver.txt @@ -102,6 +102,10 @@ implemented in the module can be called after doing: If _expiry is non-NULL, the expiry time (TTL) of the result will be returned also. +The kernel maintains an internal keyring in which it caches looked up keys. +This can be cleared by any process that has the CAP_SYS_ADMIN capability by +the use of KEYCTL_KEYRING_CLEAR on the keyring ID. + =============================== READING DNS KEYS FROM USERSPACE diff --git a/Documentation/security/00-INDEX b/Documentation/security/00-INDEX index 99b85d39751c..eeed1de546d4 100644 --- a/Documentation/security/00-INDEX +++ b/Documentation/security/00-INDEX @@ -6,6 +6,8 @@ SELinux.txt - how to get started with the SELinux security enhancement. Smack.txt - documentation on the Smack Linux Security Module. +Yama.txt + - documentation on the Yama Linux Security Module. apparmor.txt - documentation on the AppArmor security extension. credentials.txt diff --git a/Documentation/security/Yama.txt b/Documentation/security/Yama.txt new file mode 100644 index 000000000000..a9511f179069 --- /dev/null +++ b/Documentation/security/Yama.txt @@ -0,0 +1,65 @@ +Yama is a Linux Security Module that collects a number of system-wide DAC +security protections that are not handled by the core kernel itself. To +select it at boot time, specify "security=yama" (though this will disable +any other LSM). + +Yama is controlled through sysctl in /proc/sys/kernel/yama: + +- ptrace_scope + +============================================================== + +ptrace_scope: + +As Linux grows in popularity, it will become a larger target for +malware. One particularly troubling weakness of the Linux process +interfaces is that a single user is able to examine the memory and +running state of any of their processes. For example, if one application +(e.g. Pidgin) was compromised, it would be possible for an attacker to +attach to other running processes (e.g. Firefox, SSH sessions, GPG agent, +etc) to extract additional credentials and continue to expand the scope +of their attack without resorting to user-assisted phishing. + +This is not a theoretical problem. SSH session hijacking +(http://www.storm.net.nz/projects/7) and arbitrary code injection +(http://c-skills.blogspot.com/2007/05/injectso.html) attacks already +exist and remain possible if ptrace is allowed to operate as before. +Since ptrace is not commonly used by non-developers and non-admins, system +builders should be allowed the option to disable this debugging system. + +For a solution, some applications use prctl(PR_SET_DUMPABLE, ...) to +specifically disallow such ptrace attachment (e.g. ssh-agent), but many +do not. A more general solution is to only allow ptrace directly from a +parent to a child process (i.e. direct "gdb EXE" and "strace EXE" still +work), or with CAP_SYS_PTRACE (i.e. "gdb --pid=PID", and "strace -p PID" +still work as root). + +For software that has defined application-specific relationships +between a debugging process and its inferior (crash handlers, etc), +prctl(PR_SET_PTRACER, pid, ...) can be used. An inferior can declare which +other process (and its descendents) are allowed to call PTRACE_ATTACH +against it. Only one such declared debugging process can exists for +each inferior at a time. For example, this is used by KDE, Chromium, and +Firefox's crash handlers, and by Wine for allowing only Wine processes +to ptrace each other. If a process wishes to entirely disable these ptrace +restrictions, it can call prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, ...) +so that any otherwise allowed process (even those in external pid namespaces) +may attach. + +The sysctl settings are: + +0 - classic ptrace permissions: a process can PTRACE_ATTACH to any other + process running under the same uid, as long as it is dumpable (i.e. + did not transition uids, start privileged, or have called + prctl(PR_SET_DUMPABLE...) already). + +1 - restricted ptrace: a process must have a predefined relationship + with the inferior it wants to call PTRACE_ATTACH on. By default, + this relationship is that of only its descendants when the above + classic criteria is also met. To change the relationship, an + inferior can call prctl(PR_SET_PTRACER, debugger, ...) to declare + an allowed debugger PID to call PTRACE_ATTACH on the inferior. + +The original children-only logic was based on the restrictions in grsecurity. + +============================================================== diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt index fcbe7a703405..787717091421 100644 --- a/Documentation/security/keys.txt +++ b/Documentation/security/keys.txt @@ -554,6 +554,10 @@ The keyctl syscall functions are: process must have write permission on the keyring, and it must be a keyring (or else error ENOTDIR will result). + This function can also be used to clear special kernel keyrings if they + are appropriately marked if the user has CAP_SYS_ADMIN capability. The + DNS resolver cache keyring is an example of this. + (*) Link a key into a keyring: diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 7fc75e47e6d0..a048199ce866 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -5,7 +5,6 @@ menuconfig TCG_TPM tristate "TPM Hardware Support" depends on HAS_IOMEM - depends on EXPERIMENTAL select SECURITYFS ---help--- If you have a TPM security chip in your system, which diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c index 32362cf35b8d..ad7c7320dd1b 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -1221,12 +1221,13 @@ ssize_t tpm_read(struct file *file, char __user *buf, ret_size = atomic_read(&chip->data_pending); atomic_set(&chip->data_pending, 0); if (ret_size > 0) { /* relay data */ + ssize_t orig_ret_size = ret_size; if (size < ret_size) ret_size = size; mutex_lock(&chip->buffer_mutex); rc = copy_to_user(buf, chip->data_buffer, ret_size); - memset(chip->data_buffer, 0, ret_size); + memset(chip->data_buffer, 0, orig_ret_size); if (rc) ret_size = -EFAULT; diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 010547138281..b1c5280ac159 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -99,6 +99,8 @@ struct tpm_vendor_specific { wait_queue_head_t int_queue; }; +#define TPM_VID_INTEL 0x8086 + struct tpm_chip { struct device *dev; /* Device stuff */ diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c index 70fac9abb0e2..d2a70cae76df 100644 --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -367,7 +367,12 @@ static int probe_itpm(struct tpm_chip *chip) 0x00, 0x00, 0x00, 0xf1 }; size_t len = sizeof(cmd_getticks); - int rem_itpm = itpm; + bool rem_itpm = itpm; + u16 vendor = ioread16(chip->vendor.iobase + TPM_DID_VID(0)); + + /* probe only iTPMS */ + if (vendor != TPM_VID_INTEL) + return 0; itpm = 0; @@ -390,9 +395,6 @@ static int probe_itpm(struct tpm_chip *chip) out: itpm = rem_itpm; tpm_tis_ready(chip); - /* some TPMs need a break here otherwise they will not work - * correctly on the immediately subsequent command */ - msleep(chip->vendor.timeout_b); release_locality(chip, chip->vendor.locality, 0); return rc; @@ -508,7 +510,7 @@ static int tpm_tis_init(struct device *dev, resource_size_t start, resource_size_t len, unsigned int irq) { u32 vendor, intfcaps, intmask; - int rc, i, irq_s, irq_e; + int rc, i, irq_s, irq_e, probe; struct tpm_chip *chip; if (!(chip = tpm_register_hardware(dev, &tpm_tis))) @@ -538,11 +540,12 @@ static int tpm_tis_init(struct device *dev, resource_size_t start, vendor >> 16, ioread8(chip->vendor.iobase + TPM_RID(0))); if (!itpm) { - itpm = probe_itpm(chip); - if (itpm < 0) { + probe = probe_itpm(chip); + if (probe < 0) { rc = -ENODEV; goto out_err; } + itpm = (probe == 0) ? 0 : 1; } if (itpm) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 58dc117a8d78..0427c6561c84 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -13,6 +13,7 @@ #include <linux/init.h> #include <linux/wait.h> #include <linux/cdev.h> +#include <linux/idr.h> #include <linux/fs.h> #include <net/net_namespace.h> diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 501b27c18145..1c6f700f5faa 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -23,6 +23,7 @@ #include <linux/crypto.h> #include <linux/completion.h> #include <linux/module.h> +#include <linux/idr.h> #include <asm/unaligned.h> #include <scsi/scsi_device.h> #include <scsi/iscsi_proto.h> diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c index 38cb7ce8469e..1ee33a8c3fab 100644 --- a/drivers/target/iscsi/iscsi_target_login.c +++ b/drivers/target/iscsi/iscsi_target_login.c @@ -21,6 +21,7 @@ #include <linux/string.h> #include <linux/kthread.h> #include <linux/crypto.h> +#include <linux/idr.h> #include <scsi/iscsi_proto.h> #include <target/target_core_base.h> #include <target/target_core_fabric.h> diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c index c1b254487388..3cc1b251ca08 100644 --- a/fs/cifs/cifsacl.c +++ b/fs/cifs/cifsacl.c @@ -556,6 +556,7 @@ init_cifs_idmap(void) /* instruct request_key() to use this special keyring as a cache for * the results it looks up */ + set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); cred->thread_keyring = keyring; cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; root_cred = cred; diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 31778f74357d..d4f772ebd1ef 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -36,6 +36,7 @@ #include <linux/inet.h> #include <linux/in6.h> #include <linux/slab.h> +#include <linux/idr.h> #include <net/ipv6.h> #include <linux/nfs_xdr.h> #include <linux/sunrpc/bc_xprt.h> diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c index 2c05f1991e1e..a1bbf7780dfc 100644 --- a/fs/nfs/idmap.c +++ b/fs/nfs/idmap.c @@ -198,6 +198,7 @@ int nfs_idmap_init(void) if (ret < 0) goto failed_put_key; + set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); cred->thread_keyring = keyring; cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; id_resolver_cache = cred; diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index a6b62173d4c3..67bbf6e4e197 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -6,7 +6,9 @@ #include <linux/poll.h> #include <linux/proc_fs.h> #include <linux/security.h> +#include <linux/sched.h> #include <linux/namei.h> +#include <linux/mm.h> #include "internal.h" static const struct dentry_operations proc_sys_dentry_operations; diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index 46741970371b..8b4f12b33f57 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -71,6 +71,7 @@ #include <linux/module.h> #include <linux/proc_fs.h> #include <linux/security.h> +#include <linux/sched.h> #include <linux/kmod.h> #include <linux/namei.h> #include <linux/capability.h> diff --git a/fs/super.c b/fs/super.c index 6277ec6cb60a..d90e900a8a0e 100644 --- a/fs/super.c +++ b/fs/super.c @@ -32,6 +32,7 @@ #include <linux/backing-dev.h> #include <linux/rculist_bl.h> #include <linux/cleancache.h> +#include <linux/fsnotify.h> #include "internal.h" diff --git a/include/linux/key.h b/include/linux/key.h index 5253471cd2ea..1600ebf717a7 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -155,6 +155,7 @@ struct key { #define KEY_FLAG_IN_QUOTA 3 /* set if key consumes quota */ #define KEY_FLAG_USER_CONSTRUCT 4 /* set if key is being constructed in userspace */ #define KEY_FLAG_NEGATIVE 5 /* set if key is negative */ +#define KEY_FLAG_ROOT_CAN_CLEAR 6 /* set if key can be cleared by root without permission */ /* the description string * - this is used to match a key against search criteria diff --git a/include/linux/prctl.h b/include/linux/prctl.h index 7ddc7f1b480f..a0413ac3abe8 100644 --- a/include/linux/prctl.h +++ b/include/linux/prctl.h @@ -114,4 +114,11 @@ # define PR_SET_MM_START_BRK 6 # define PR_SET_MM_BRK 7 +/* + * Set specific pid that is allowed to ptrace the current task. + * A value of 0 mean "no process". + */ +#define PR_SET_PTRACER 0x59616d61 +# define PR_SET_PTRACER_ANY ((unsigned long)-1) + #endif /* _LINUX_PRCTL_H */ diff --git a/include/linux/security.h b/include/linux/security.h index c8949385e56e..673afbb8238a 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -22,22 +22,36 @@ #ifndef __LINUX_SECURITY_H #define __LINUX_SECURITY_H -#include <linux/fs.h> -#include <linux/fsnotify.h> -#include <linux/binfmts.h> -#include <linux/dcache.h> -#include <linux/signal.h> -#include <linux/resource.h> -#include <linux/sem.h> -#include <linux/shm.h> -#include <linux/mm.h> /* PAGE_ALIGN */ -#include <linux/msg.h> -#include <linux/sched.h> #include <linux/key.h> -#include <linux/xfrm.h> +#include <linux/capability.h> #include <linux/slab.h> -#include <linux/xattr.h> -#include <net/flow.h> +#include <linux/err.h> + +struct linux_binprm; +struct cred; +struct rlimit; +struct siginfo; +struct sem_array; +struct sembuf; +struct kern_ipc_perm; +struct audit_context; +struct super_block; +struct inode; +struct dentry; +struct file; +struct vfsmount; +struct path; +struct qstr; +struct nameidata; +struct iattr; +struct fown_struct; +struct file_operations; +struct shmid_kernel; +struct msg_msg; +struct msg_queue; +struct xattr; +struct xfrm_sec_ctx; +struct mm_struct; /* Maximum number of letters for an LSM name string */ #define SECURITY_NAME_MAX 10 @@ -49,6 +63,7 @@ struct ctl_table; struct audit_krule; struct user_namespace; +struct timezone; /* * These functions are in security/capability.c and are used @@ -131,18 +146,6 @@ struct request_sock; |