09 Feb, 2010

1 commit


23 Dec, 2009

1 commit

  • * pull ACC_MODE to fs.h; we have several copies all over the place
    * nightmarish expression calculating f_mode by f_flags deserves a helper
    too (OPEN_FMODE(flags))

    Signed-off-by: Al Viro

    Al Viro
     

24 Sep, 2009

1 commit


24 Jun, 2009

4 commits

  • If syscall removes the root of subtree being watched, we
    definitely do not want the rules refering that subtree
    to be destroyed without the syscall in question having
    a chance to match them.

    Signed-off-by: Al Viro

    Al Viro
     
  • A number of places in the audit system we send an op= followed by a string
    that includes spaces. Somehow this works but it's just wrong. This patch
    moves all of those that I could find to be quoted.

    Example:

    Change From: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1
    subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op=remove rule
    key="number2" list=4 res=0

    Change To: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1
    subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op="remove rule"
    key="number2" list=4 res=0

    Signed-off-by: Eric Paris

    Eric Paris
     
  • In preparation for converting audit to use fsnotify instead of inotify we
    seperate the inode watching code into it's own file. This is similar to
    how the audit tree watching code is already seperated into audit_tree.c

    Signed-off-by: Eric Paris

    Eric Paris
     
  • The audit execve record splitting code estimates the length of the message
    generated. But it forgot to include the "" that wrap each string in its
    estimation. This means that execve messages with lots of tiny (1-2 byte)
    arguments could still cause records greater than 8k to be emitted. Simply
    fix the estimate.

    Signed-off-by: Eric Paris

    Eric Paris
     

06 Apr, 2009

5 commits

  • audit_log_d_path had spaces in the strings which would be emitted on the
    error paths. This patch simply replaces those spaces with an _ or removes
    the needless spaces entirely.

    Signed-off-by: Eric Paris
    Signed-off-by: Al Viro

    Eric Paris
     
  • after 0590b9335a1c72a3f0defcc6231287f7817e07c8 audit_set_auditable() is now only
    used by the audit tree code. If CONFIG_AUDIT_TREE is unset it will be defined
    but unused. This patch simply moves the function inside a CONFIG_AUDIT_TREE
    block.

    cc1: warnings being treated as errors
    /home/acme_unencrypted/git/linux-2.6-tip/kernel/auditsc.c:745: error: ‘audit_set_auditable’ defined but not used
    make[2]: *** [kernel/auditsc.o] Error 1
    make[1]: *** [kernel] Error 2
    make[1]: *** Waiting for unfinished jobs....

    Signed-off-by: Eric Paris
    Signed-off-by: Al Viro

    Eric Paris
     
  • The audit subsystem treats syscall return codes as type long, unfortunately
    the audit_get_context() function mistakenly converts the return code to an
    int type in the parameters which could cause problems on systems where the
    sizeof(int) != sizeof(long).

    Signed-off-by: Paul Moore
    Signed-off-by: Al Viro

    Paul Moore
     
  • Fix auditsc kernel-doc notation:

    Warning(linux-2.6.28-git7//kernel/auditsc.c:2156): No description found for parameter 'attr'
    Warning(linux-2.6.28-git7//kernel/auditsc.c:2156): Excess function parameter 'u_attr' description in '__audit_mq_open'
    Warning(linux-2.6.28-git7//kernel/auditsc.c:2204): No description found for parameter 'notification'
    Warning(linux-2.6.28-git7//kernel/auditsc.c:2204): Excess function parameter 'u_notification' description in '__audit_mq_notify'

    Signed-off-by: Randy Dunlap
    cc: Al Viro
    cc: Eric Paris
    Signed-off-by: Al Viro

    Randy Dunlap
     
  • (updated)
    Added hunk that changes the comment, the rest is the same.

    EXECVE records contain a newline after every argument. auditd converts
    "\n" to " " so you cannot see newlines even in raw logs, but they're
    there nevertheless. If you're not using auditd, you need to work round
    them. These '\n' chars are can be easily replaced by spaces when
    creating record in kernel. Note there is no need for trailing '\n' in
    an audit record.

    record before this patch:
    "type=EXECVE msg=audit(1231421801.566:31): argc=4 a0=\"./test\"\na1=\"a\"\na2=\"b\"\na3=\"c\"\n"

    record after this patch:
    "type=EXECVE msg=audit(1231421801.566:31): argc=4 a0=\"./test\" a1=\"a\" a2=\"b\" a3=\"c\""

    Signed-off-by: Jiri Pirko
    Acked-by: Eric Paris
    Signed-off-by: Al Viro

    Jiri Pirko
     

01 Apr, 2009

1 commit


05 Jan, 2009

12 commits


25 Dec, 2008

1 commit


09 Dec, 2008

3 commits


14 Nov, 2008

4 commits

  • Inaugurate copy-on-write credentials management. This uses RCU to manage the
    credentials pointer in the task_struct with respect to accesses by other tasks.
    A process may only modify its own credentials, and so does not need locking to
    access or modify its own credentials.

    A mutex (cred_replace_mutex) is added to the task_struct to control the effect
    of PTRACE_ATTACHED on credential calculations, particularly with respect to
    execve().

    With this patch, the contents of an active credentials struct may not be
    changed directly; rather a new set of credentials must be prepared, modified
    and committed using something like the following sequence of events:

    struct cred *new = prepare_creds();
    int ret = blah(new);
    if (ret < 0) {
    abort_creds(new);
    return ret;
    }
    return commit_creds(new);

    There are some exceptions to this rule: the keyrings pointed to by the active
    credentials may be instantiated - keyrings violate the COW rule as managing
    COW keyrings is tricky, given that it is possible for a task to directly alter
    the keys in a keyring in use by another task.

    To help enforce this, various pointers to sets of credentials, such as those in
    the task_struct, are declared const. The purpose of this is compile-time
    discouragement of altering credentials through those pointers. Once a set of
    credentials has been made public through one of these pointers, it may not be
    modified, except under special circumstances:

    (1) Its reference count may incremented and decremented.

    (2) The keyrings to which it points may be modified, but not replaced.

    The only safe way to modify anything else is to create a replacement and commit
    using the functions described in Documentation/credentials.txt (which will be
    added by a later patch).

    This patch and the preceding patches have been tested with the LTP SELinux
    testsuite.

    This patch makes several logical sets of alteration:

    (1) execve().

    This now prepares and commits credentials in various places in the
    security code rather than altering the current creds directly.

    (2) Temporary credential overrides.

    do_coredump() and sys_faccessat() now prepare their own credentials and
    temporarily override the ones currently on the acting thread, whilst
    preventing interference from other threads by holding cred_replace_mutex
    on the thread being dumped.

    This will be replaced in a future patch by something that hands down the
    credentials directly to the functions being called, rather than altering
    the task's objective credentials.

    (3) LSM interface.

    A number of functions have been changed, added or removed:

    (*) security_capset_check(), ->capset_check()
    (*) security_capset_set(), ->capset_set()

    Removed in favour of security_capset().

    (*) security_capset(), ->capset()

    New. This is passed a pointer to the new creds, a pointer to the old
    creds and the proposed capability sets. It should fill in the new
    creds or return an error. All pointers, barring the pointer to the
    new creds, are now const.

    (*) security_bprm_apply_creds(), ->bprm_apply_creds()

    Changed; now returns a value, which will cause the process to be
    killed if it's an error.

    (*) security_task_alloc(), ->task_alloc_security()

    Removed in favour of security_prepare_creds().

    (*) security_cred_free(), ->cred_free()

    New. Free security data attached to cred->security.

    (*) security_prepare_creds(), ->cred_prepare()

    New. Duplicate any security data attached to cred->security.

    (*) security_commit_creds(), ->cred_commit()

    New. Apply any security effects for the upcoming installation of new
    security by commit_creds().

    (*) security_task_post_setuid(), ->task_post_setuid()

    Removed in favour of security_task_fix_setuid().

    (*) security_task_fix_setuid(), ->task_fix_setuid()

    Fix up the proposed new credentials for setuid(). This is used by
    cap_set_fix_setuid() to implicitly adjust capabilities in line with
    setuid() changes. Changes are made to the new credentials, rather
    than the task itself as in security_task_post_setuid().

    (*) security_task_reparent_to_init(), ->task_reparent_to_init()

    Removed. Instead the task being reparented to init is referred
    directly to init's credentials.

    NOTE! This results in the loss of some state: SELinux's osid no
    longer records the sid of the thread that forked it.

    (*) security_key_alloc(), ->key_alloc()
    (*) security_key_permission(), ->key_permission()

    Changed. These now take cred pointers rather than task pointers to
    refer to the security context.

    (4) sys_capset().

    This has been simplified and uses less locking. The LSM functions it
    calls have been merged.

    (5) reparent_to_kthreadd().

    This gives the current thread the same credentials as init by simply using
    commit_thread() to point that way.

    (6) __sigqueue_alloc() and switch_uid()

    __sigqueue_alloc() can't stop the target task from changing its creds
    beneath it, so this function gets a reference to the currently applicable
    user_struct which it then passes into the sigqueue struct it returns if
    successful.

    switch_uid() is now called from commit_creds(), and possibly should be
    folded into that. commit_creds() should take care of protecting
    __sigqueue_alloc().

    (7) [sg]et[ug]id() and co and [sg]et_current_groups.

    The set functions now all use prepare_creds(), commit_creds() and
    abort_creds() to build and check a new set of credentials before applying
    it.

    security_task_set[ug]id() is called inside the prepared section. This
    guarantees that nothing else will affect the creds until we've finished.

    The calling of set_dumpable() has been moved into commit_creds().

    Much of the functionality of set_user() has been moved into
    commit_creds().

    The get functions all simply access the data directly.

    (8) security_task_prctl() and cap_task_prctl().

    security_task_prctl() has been modified to return -ENOSYS if it doesn't
    want to handle a function, or otherwise return the return value directly
    rather than through an argument.

    Additionally, cap_task_prctl() now prepares a new set of credentials, even
    if it doesn't end up using it.

    (9) Keyrings.

    A number of changes have been made to the keyrings code:

    (a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have
    all been dropped and built in to the credentials functions directly.
    They may want separating out again later.

    (b) key_alloc() and search_process_keyrings() now take a cred pointer
    rather than a task pointer to specify the security context.

    (c) copy_creds() gives a new thread within the same thread group a new
    thread keyring if its parent had one, otherwise it discards the thread
    keyring.

    (d) The authorisation key now points directly to the credentials to extend
    the search into rather pointing to the task that carries them.

    (e) Installing thread, process or session keyrings causes a new set of
    credentials to be created, even though it's not strictly necessary for
    process or session keyrings (they're shared).

    (10) Usermode helper.

    The usermode helper code now carries a cred struct pointer in its
    subprocess_info struct instead of a new session keyring pointer. This set
    of credentials is derived from init_cred and installed on the new process
    after it has been cloned.

    call_usermodehelper_setup() allocates the new credentials and
    call_usermodehelper_freeinfo() discards them if they haven't been used. A
    special cred function (prepare_usermodeinfo_creds()) is provided
    specifically for call_usermodehelper_setup() to call.

    call_usermodehelper_setkeys() adjusts the credentials to sport the
    supplied keyring as the new session keyring.

    (11) SELinux.

    SELinux has a number of changes, in addition to those to support the LSM
    interface changes mentioned above:

    (a) selinux_setprocattr() no longer does its check for whether the
    current ptracer can access processes with the new SID inside the lock
    that covers getting the ptracer's SID. Whilst this lock ensures that
    the check is done with the ptracer pinned, the result is only valid
    until the lock is released, so there's no point doing it inside the
    lock.

    (12) is_single_threaded().

    This function has been extracted from selinux_setprocattr() and put into
    a file of its own in the lib/ directory as join_session_keyring() now
    wants to use it too.

    The code in SELinux just checked to see whether a task shared mm_structs
    with other tasks (CLONE_VM), but that isn't good enough. We really want
    to know if they're part of the same thread group (CLONE_THREAD).

    (13) nfsd.

    The NFS server daemon now has to use the COW credentials to set the
    credentials it is going to use. It really needs to pass the credentials
    down to the functions it calls, but it can't do that until other patches
    in this series have been applied.

    Signed-off-by: David Howells
    Acked-by: James Morris
    Signed-off-by: James Morris

    David Howells
     
  • Use RCU to access another task's creds and to release a task's own creds.
    This means that it will be possible for the credentials of a task to be
    replaced without another task (a) requiring a full lock to read them, and (b)
    seeing deallocated memory.

    Signed-off-by: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • Separate the task security context from task_struct. At this point, the
    security data is temporarily embedded in the task_struct with two pointers
    pointing to it.

    Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
    entry.S via asm-offsets.

    With comment fixes Signed-off-by: Marc Dionne

    Signed-off-by: David Howells
    Acked-by: James Morris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    David Howells
     
  • Wrap access to task credentials so that they can be separated more easily from
    the task_struct during the introduction of COW creds.

    Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

    Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
    sense to use RCU directly rather than a convenient wrapper; these will be
    addressed by later patches.

    Signed-off-by: David Howells
    Reviewed-by: James Morris
    Acked-by: Serge Hallyn
    Cc: Al Viro
    Cc: linux-audit@redhat.com
    Cc: containers@lists.linux-foundation.org
    Cc: linux-mm@kvack.org
    Signed-off-by: James Morris

    David Howells
     

11 Nov, 2008

3 commits

  • actual capbilities being added/removed. This patch adds a new record type
    which emits the target pid and the eff, inh, and perm cap sets.

    example output if you audit capset syscalls would be:

    type=SYSCALL msg=audit(1225743140.465:76): arch=c000003e syscall=126 success=yes exit=0 a0=17f2014 a1=17f201c a2=80000000 a3=7fff2ab7f060 items=0 ppid=2160 pid=2223 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=1 comm="setcap" exe="/usr/sbin/setcap" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
    type=UNKNOWN[1322] msg=audit(1225743140.465:76): pid=0 cap_pi=ffffffffffffffff cap_pp=ffffffffffffffff cap_pe=ffffffffffffffff

    Signed-off-by: Eric Paris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    Eric Paris
     
  • non-zero pE we will crate a new audit record which contains the entire set
    of known information about the executable in question, fP, fI, fE, fversion
    and includes the process's pE, pI, pP. Before and after the bprm capability
    are applied. This record type will only be emitted from execve syscalls.

    an example of making ping use fcaps instead of setuid:

    setcap "cat_net_raw+pe" /bin/ping

    type=SYSCALL msg=audit(1225742021.015:236): arch=c000003e syscall=59 success=yes exit=0 a0=1457f30 a1=14606b0 a2=1463940 a3=321b770a70 items=2 ppid=2929 pid=2963 auid=0 uid=500 gid=500 euid=500 suid=500 fsuid=500 egid=500 sgid=500 fsgid=500 tty=pts0 ses=3 comm="ping" exe="/bin/ping" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
    type=UNKNOWN[1321] msg=audit(1225742021.015:236): fver=2 fp=0000000000002000 fi=0000000000000000 fe=1 old_pp=0000000000000000 old_pi=0000000000000000 old_pe=0000000000000000 new_pp=0000000000002000 new_pi=0000000000000000 new_pe=0000000000002000
    type=EXECVE msg=audit(1225742021.015:236): argc=2 a0="ping" a1="127.0.0.1"
    type=CWD msg=audit(1225742021.015:236): cwd="/home/test"
    type=PATH msg=audit(1225742021.015:236): item=0 name="/bin/ping" inode=49256 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ping_exec_t:s0 cap_fp=0000000000002000 cap_fe=1 cap_fver=2
    type=PATH msg=audit(1225742021.015:236): item=1 name=(null) inode=507915 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ld_so_t:s0

    Signed-off-by: Eric Paris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    Eric Paris
     
  • records of any file that has file capabilities set. Files which do not
    have fcaps set will not have different PATH records.

    An example audit record if you run:
    setcap "cap_net_admin+pie" /bin/bash
    /bin/bash

    type=SYSCALL msg=audit(1225741937.363:230): arch=c000003e syscall=59 success=yes exit=0 a0=2119230 a1=210da30 a2=20ee290 a3=8 items=2 ppid=2149 pid=2923 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=3 comm="ping" exe="/bin/ping" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
    type=EXECVE msg=audit(1225741937.363:230): argc=2 a0="ping" a1="www.google.com"
    type=CWD msg=audit(1225741937.363:230): cwd="/root"
    type=PATH msg=audit(1225741937.363:230): item=0 name="/bin/ping" inode=49256 dev=fd:00 mode=0104755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ping_exec_t:s0 cap_fp=0000000000002000 cap_fi=0000000000002000 cap_fe=1 cap_fver=2
    type=PATH msg=audit(1225741937.363:230): item=1 name=(null) inode=507915 dev=fd:00 mode=0100755 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:ld_so_t:s0

    Signed-off-by: Eric Paris
    Acked-by: Serge Hallyn
    Signed-off-by: James Morris

    Eric Paris
     

14 Oct, 2008

1 commit


02 Sep, 2008

1 commit


04 Aug, 2008

1 commit


02 Aug, 2008

1 commit