18 Apr, 2012

1 commit

  • A kernel with Smack enabled will fail if tmpfs has xattr support.

    Move the initialization of predefined Smack label
    list entries to the LSM initialization from the
    smackfs setup. This became an issue when tmpfs
    acquired xattr support, but was never correct.

    Signed-off-by: Casey Schaufler
    Signed-off-by: James Morris

    Casey Schaufler
     

11 Apr, 2012

1 commit

  • This fixes builds where CONFIG_AUDIT is not defined and
    CONFIG_SECURITY_SMACK=y.

    This got introduced by the stack-usage reducation commit 48c62af68a40
    ("LSM: shrink the common_audit_data data union").

    Signed-off-by: Kees Cook
    Acked-by: Eric Paris
    Signed-off-by: Linus Torvalds

    Kees Cook
     

04 Apr, 2012

3 commits

  • It just bloats the audit data structure for no good reason, since the
    only time those fields are filled are just before calling the
    common_lsm_audit() function, which is also the only user of those
    fields.

    So just make them be the arguments to common_lsm_audit(), rather than
    bloating that structure that is passed around everywhere, and is
    initialized in hot paths.

    Signed-off-by: Linus Torvalds

    Linus Torvalds
     
  • After shrinking the common_audit_data stack usage for private LSM data I'm
    not going to shrink the data union. To do this I'm going to move anything
    larger than 2 void * ptrs to it's own structure and require it to be declared
    separately on the calling stack. Thus hot paths which don't need more than
    a couple pointer don't have to declare space to hold large unneeded
    structures. I could get this down to one void * by dealing with the key
    struct and the struct path. We'll see if that is helpful after taking care of
    networking.

    Signed-off-by: Eric Paris
    Signed-off-by: Linus Torvalds

    Eric Paris
     
  • Linus found that the gigantic size of the common audit data caused a big
    perf hit on something as simple as running stat() in a loop. This patch
    requires LSMs to declare the LSM specific portion separately rather than
    doing it in a union. Thus each LSM can be responsible for shrinking their
    portion and don't have to pay a penalty just because other LSMs have a
    bigger space requirement.

    Signed-off-by: Eric Paris
    Signed-off-by: Linus Torvalds

    Eric Paris
     

14 Feb, 2012

1 commit


07 Jan, 2012

1 commit


12 Nov, 2011

1 commit

  • Commit 272cd7a8c67dd40a31ecff76a503bbb84707f757 introduced
    a change to the way rule lists are handled and reported in
    the smackfs filesystem. One of the issues addressed had to
    do with the termination of read requests on /smack/load.
    This change introduced a error in /smack/cipso, which shares
    some of the same list processing code.

    This patch updates all the file access list handling in
    smackfs to use the code introduced for /smack/load.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     

21 Oct, 2011

1 commit


19 Oct, 2011

1 commit


14 Oct, 2011

1 commit

  • On some build configurations PER_CLEAR_ON_SETID symbol was not
    found when compiling smack_lsm.c. This patch fixes the issue by
    explicitly doing #include .

    Signed-off-by: Jarkko Sakkinen
    Signed-off-by: Casey Schaufler

    Jarkko Sakkinen
     

13 Oct, 2011

7 commits

  • Small fix for the output of access SmackFS file. Use string
    is instead of byte. Makes it easier to extend API if it is
    needed.

    Signed-off-by: Jarkko Sakkinen

    Jarkko Sakkinen
     
  • Protections for domain transition:

    - BPRM unsafe flags
    - Secureexec
    - Clear unsafe personality bits.
    - Clear parent death signal

    Signed-off-by: Jarkko Sakkinen

    Jarkko Sakkinen
     
  • This patch is targeted for the smack-next tree.

    This patch takes advantage of the recent changes for performance
    and points the packet labels on UDS connect at the output label of
    the far side. This makes getsockopt(...SO_PEERCRED...) function
    properly. Without this change the getsockopt does not provide any
    information.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     
  • There are a number of comments in the Smack code that
    are either malformed or include code. This patch cleans
    them up.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     
  • Al Viro pointed out that the processing of fcntl done
    by Smack appeared poorly designed. He was right. There
    are three things that required change. Most obviously,
    the list of commands that really imply writing is limited
    to those involving file locking and signal handling.
    The initialization if the file security blob was
    incomplete, requiring use of a heretofore unused LSM hook.
    Finally, the audit information coming from a helper
    masked the identity of the LSM hook. This patch corrects
    all three of these defects.

    This is targeted for the smack-next tree pending comments.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     
  • This patch is targeted for the smack-next tree.

    Smack access checks suffer from two significant performance
    issues. In cases where there are large numbers of rules the
    search of the single list of rules is wasteful. Comparing the
    string values of the smack labels is less efficient than a
    numeric comparison would.

    These changes take advantage of the Smack label list, which
    maintains the mapping of Smack labels to secids and optional
    CIPSO labels. Because the labels are kept perpetually, an
    access check can be done strictly based on the address of the
    label in the list without ever looking at the label itself.
    Rather than keeping one global list of rules the rules with
    a particular subject label can be based off of that label
    list entry. The access check need never look at entries that
    do not use the current subject label.

    This requires that packets coming off the network with
    CIPSO direct Smack labels that have never been seen before
    be treated carefully. The only case where they could be
    delivered is where the receiving socket has an IPIN star
    label, so that case is explicitly addressed.

    On a system with 39,800 rules (200 labels in all permutations)
    a system with this patch runs an access speed test in 5% of
    the time of the old version. That should be a best case
    improvement. If all of the rules are associated with the
    same subject label and all of the accesses are for processes
    with that label (unlikely) the improvement is about 30%.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     
  • Adds a new file into SmackFS called 'access'. Wanted
    Smack permission is written into /smack/access.
    After that result can be read from the opened file.
    If access applies result contains 1 and otherwise
    0. File access is protected from race conditions
    by using simple_transaction_get()/set() API.

    Fixes from the previous version:
    - Removed smack.h changes, refactoring left-over
    from previous version.
    - Removed #include , refactoring
    left-over from previous version.

    Signed-off-by: Jarkko Sakkinen
    Signed-off-by: Casey Schaufler

    Jarkko Sakkinen
     

02 Aug, 2011

1 commit


20 Jul, 2011

1 commit


24 May, 2011

1 commit


26 Apr, 2011

3 commits


25 Apr, 2011

1 commit

  • 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
    Signed-off-by: Eric Paris

    Andi Kleen
     

23 Apr, 2011

1 commit

  • 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

    Andi Kleen
     

31 Mar, 2011

1 commit


08 Mar, 2011

1 commit


10 Feb, 2011

2 commits


09 Feb, 2011

1 commit

  • The mmap policy enforcement was not properly handling the
    interaction between the global and local rule lists.
    Instead of going through one and then the other, which
    missed the important case where a rule specified that
    there should be no access, combine the access limitations
    where there is a rule in each list.

    Signed-off-by: Casey Schaufler
    Signed-off-by: James Morris

    Casey Schaufler
     

02 Feb, 2011

1 commit

  • 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

    Eric Paris
     

18 Jan, 2011

1 commit

  • In the embedded world there are often situations
    where libraries are updated from a variety of sources,
    for a variety of reasons, and with any number of
    security characteristics. These differences
    might include privilege required for a given library
    provided interface to function properly, as occurs
    from time to time in graphics libraries. There are
    also cases where it is important to limit use of
    libraries based on the provider of the library and
    the security aware application may make choices
    based on that criteria.

    These issues are addressed by providing an additional
    Smack label that may optionally be assigned to an object,
    the SMACK64MMAP attribute. An mmap operation is allowed
    if there is no such attribute.

    If there is a SMACK64MMAP attribute the mmap is permitted
    only if a subject with that label has all of the access
    permitted a subject with the current task label.

    Security aware applications may from time to time
    wish to reduce their "privilege" to avoid accidental use
    of privilege. One case where this arises is the
    environment in which multiple sources provide libraries
    to perform the same functions. An application may know
    that it should eschew services made available from a
    particular vendor, or of a particular version.

    In support of this a secondary list of Smack rules has
    been added that is local to the task. This list is
    consulted only in the case where the global list has
    approved access. It can only further restrict access.
    Unlike the global last, if no entry is found on the
    local list access is granted. An application can add
    entries to its own list by writing to /smack/load-self.

    The changes appear large as they involve refactoring
    the list handling to accomodate there being more
    than one rule list.

    Signed-off-by: Casey Schaufler

    Casey Schaufler
     

10 Jan, 2011

1 commit


06 Jan, 2011

1 commit

  • unix_release() can asynchornously set socket->sk to NULL, and
    it does so without holding the unix_state_lock() on "other"
    during stream connects.

    However, the reverse mapping, sk->sk_socket, is only transitioned
    to NULL under the unix_state_lock().

    Therefore make the security hooks follow the reverse mapping instead
    of the forward mapping.

    Reported-by: Jeremy Fitzhardinge
    Reported-by: Linus Torvalds
    Signed-off-by: David S. Miller

    David S. Miller
     

08 Dec, 2010

1 commit

  • In a situation where Smack access rules allow processes
    with multiple labels to write to a directory it is easy
    to get into a situation where the directory gets cluttered
    with files that the owner can't deal with because while
    they could be written to the directory a process at the
    label of the directory can't write them. This is generally
    the desired behavior, but when it isn't it is a real
    issue.

    This patch introduces a new attribute SMACK64TRANSMUTE that
    instructs Smack to create the file with the label of the directory
    under certain circumstances.

    A new access mode, "t" for transmute, is made available to
    Smack access rules, which are expanded from "rwxa" to "rwxat".
    If a file is created in a directory marked as transmutable
    and if access was granted to perform the operation by a rule
    that included the transmute mode, then the file gets the
    Smack label of the directory instead of the Smack label of the
    creating process.

    Note that this is equivalent to creating an empty file at the
    label of the directory and then having the other process write
    to it. The transmute scheme requires that both the access rule
    allows transmutation and that the directory be explicitly marked.

    Signed-off-by: Jarkko Sakkinen
    Signed-off-by: Casey Schaufler

    Jarkko Sakkinen
     

02 Dec, 2010

1 commit

  • SMACK64EXEC. It defines label that is used while task is
    running.

    Exception: in smack_task_wait() child task is checked
    for write access to parent task using label inherited
    from the task that forked it.

    Fixed issues from previous submit:
    - SMACK64EXEC was not read when SMACK64 was not set.
    - inode security blob was not updated after setting
    SMACK64EXEC
    - inode security blob was not updated when removing
    SMACK64EXEC

    Casey Schaufler
     

29 Nov, 2010

1 commit

  • This patch addresses a number of long standing issues
    with the way Smack treats UNIX domain sockets.

    All access control was being done based on the label of
    the file system object. This is inconsistant with the
    internet domain, in which access is done based on the
    IPIN and IPOUT attributes of the socket. As a result
    of the inode label policy it was not possible to use
    a UDS socket for label cognizant services, including
    dbus and the X11 server.

    Support for SCM_PEERSEC on UDS sockets is also provided.

    Signed-off-by: Casey Schaufler
    Signed-off-by: James Morris

    Casey Schaufler
     

16 Nov, 2010

1 commit

  • 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

    Eric Paris
     

29 Oct, 2010

1 commit