[ Upstream commit ae3b564179 ]
Several u->addr and u->path users are not holding any locks in
common with unix_bind(). unix_state_lock() is useless for those
purposes.
u->addr is assign-once and *(u->addr) is fully set up by the time
we set u->addr (all under unix_table_lock). u->path is also
set in the same critical area, also before setting u->addr, and
any unix_sock with ->path filled will have non-NULL ->addr.
So setting ->addr with smp_store_release() is all we need for those
"lockless" users - just have them fetch ->addr with smp_load_acquire()
and don't even bother looking at ->path if they see NULL ->addr.
Users of ->addr and ->path fall into several classes now:
1) ones that do smp_load_acquire(u->addr) and access *(u->addr)
and u->path only if smp_load_acquire() has returned non-NULL.
2) places holding unix_table_lock. These are guaranteed that
*(u->addr) is seen fully initialized. If unix_sock is in one of the
"bound" chains, so's ->path.
3) unix_sock_destructor() using ->addr is safe. All places
that set u->addr are guaranteed to have seen all stores *(u->addr)
while holding a reference to u and unix_sock_destructor() is called
when (atomic) refcount hits zero.
4) unix_release_sock() using ->path is safe. unix_bind()
is serialized wrt unix_release() (normally - by struct file
refcount), and for the instances that had ->path set by unix_bind()
unix_release_sock() comes from unix_release(), so they are fine.
Instances that had it set in unix_stream_connect() either end up
attached to a socket (in unix_accept()), in which case the call
chain to unix_release_sock() and serialization are the same as in
the previous case, or they never get accept'ed and unix_release_sock()
is called when the listener is shut down and its queue gets purged.
In that case the listener's queue lock provides the barriers needed -
unix_stream_connect() shoves our unix_sock into listener's queue
under that lock right after having set ->path and eventual
unix_release_sock() caller picks them from that queue under the
same lock right before calling unix_release_sock().
5) unix_find_other() use of ->path is pointless, but safe -
it happens with successful lookup by (abstract) name, so ->path.dentry
is guaranteed to be NULL there.
earlier-variant-reviewed-by: "Paul E. McKenney" <paulmck@linux.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4aa68e07d8 upstream.
When checking for permission to view keys whilst reading from
/proc/keys, we should use the credentials with which the /proc/keys file
was opened. This is because, in a classic type of exploit, it can be
possible to bypass checks for the *current* credentials by passing the
file descriptor to a suid program.
Following commit 34dbbcdbf6 ("Make file credentials available to the
seqfile interfaces") we can finally fix it. So let's do it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Zubin Mithra <zsm@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ede0fa98a9 upstream.
syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
called from construct_alloc_key() during sys_request_key(), because the
length of the key description was never calculated.
The problem is that we rely on ->desc_len being initialized by
search_process_keyrings(), specifically by search_nested_keyrings().
But, if the process isn't subscribed to any keyrings that never happens.
Fix it by always initializing keyring_index_key::desc_len as soon as the
description is set, like we already do in some places.
The following program reproduces the BUG_ON() when it's run as root and
no session keyring has been installed. If it doesn't work, try removing
pam_keyinit.so from /etc/pam.d/login and rebooting.
#include <stdlib.h>
#include <unistd.h>
#include <keyutils.h>
int main(void)
{
int id = add_key("keyring", "syz", NULL, 0, KEY_SPEC_USER_KEYRING);
keyctl_setperm(id, KEY_OTH_WRITE);
setreuid(5000, 5000);
request_key("user", "desc", "", id);
}
Reported-by: syzbot+ec24e95ea483de0a24da@syzkaller.appspotmail.com
Fixes: b2a4df200d ("KEYS: Expand the capacity of a keyring")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a08bf91ce2 upstream.
If the sysctl 'kernel.keys.maxkeys' is set to some number n, then
actually users can only add up to 'n - 1' keys. Likewise for
'kernel.keys.maxbytes' and the root_* versions of these sysctls. But
these sysctls are apparently supposed to be *maximums*, as per their
names and all documentation I could find -- the keyrings(7) man page,
Documentation/security/keys/core.rst, and all the mentions of EDQUOT
meaning that the key quota was *exceeded* (as opposed to reached).
Thus, fix the code to allow reaching the quotas exactly.
Fixes: 0b77f5bfb4 ("keys: make the keyring quotas controllable through /proc/sys")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5b841bfab6 ]
Function smack_key_permission() only issues smack requests for the
following operations:
- KEY_NEED_READ (issues MAY_READ)
- KEY_NEED_WRITE (issues MAY_WRITE)
- KEY_NEED_LINK (issues MAY_WRITE)
- KEY_NEED_SETATTR (issues MAY_WRITE)
A blank smack request is issued in all other cases, resulting in
smack access being granted if there is any rule defined between
subject and object, or denied with -EACCES otherwise.
Request MAY_READ access for KEY_NEED_SEARCH and KEY_NEED_VIEW.
Fix the logic in the unlikely case when both MAY_READ and
MAY_WRITE are needed. Validate access permission field for valid
contents.
Signed-off-by: Zoran Markovic <zmarkovic@sierrawireless.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2cbdcb882f ]
If a superblock has the MS_SUBMOUNT flag set, we should always allow
mounting it. These mounts are done automatically by the kernel either as
part of mounting some parent mount (e.g. debugfs always mounts tracefs
under "tracing" for compatibility) or they are mounted automatically as
needed on subdirectory accesses (e.g. NFS crossmnt mounts). Since such
automounts are either an implicit consequence of the parent mount (which
is already checked) or they can happen during regular accesses (where it
doesn't make sense to check against the current task's context), the
mount permission check should be skipped for them.
Without this patch, attempts to access contents of an automounted
directory can cause unexpected SELinux denials.
In the current kernel tree, the MS_SUBMOUNT flag is set only via
vfs_submount(), which is called only from the following places:
- AFS, when automounting special "symlinks" referencing other cells
- CIFS, when automounting "referrals"
- NFS, when automounting subtrees
- debugfs, when automounting tracefs
In all cases the submounts are meant to be transparent to the user and
it makes sense that if mounting the master is allowed, then so should be
the automounts. Note that CAP_SYS_ADMIN capability checking is already
skipped for (SB_KERNMOUNT|SB_SUBMOUNT) in:
- sget_userns() in fs/super.c:
if (!(flags & (SB_KERNMOUNT|SB_SUBMOUNT)) &&
!(type->fs_flags & FS_USERNS_MOUNT) &&
!capable(CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);
- sget() in fs/super.c:
/* Ensure the requestor has permissions over the target filesystem */
if (!(flags & (SB_KERNMOUNT|SB_SUBMOUNT)) && !ns_capable(user_ns, CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);
Verified internally on patched RHEL 7.6 with a reproducer using
NFS+httpd and selinux-tesuite.
Fixes: 93faccbbfa ("fs: Better permission checking for submounts")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5b0e7310a2 upstream.
levdatum->level can be NULL if we encounter an error while loading
the policy during sens_read prior to initializing it. Make sure
sens_destroy handles that case correctly.
Reported-by: syzbot+6664500f0f18f07a5c0e@syzkaller.appspotmail.com
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a5795fd38e upstream.
From: Casey Schaufler <casey@schaufler-ca.com>
Check that the cred security blob has been set before trying
to clean it up. There is a case during credential initialization
that could result in this.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Reported-by: syzbot+69ca07954461f189e808@syzkaller.appspotmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9474f4e7cd upstream.
It's possible that a pid has died before we take the rcu lock, in which
case we can't walk the ancestry list as it may be detached. Instead, check
for death first before doing the walk.
Reported-by: syzbot+a9ac39bf55329e206219@syzkaller.appspotmail.com
Fixes: 2d514487fa ("security: Yama LSM")
Cc: stable@vger.kernel.org
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e2598077dc upstream.
Intermittently security.ima is not being written for new files. This
patch re-initializes the new slab iint->atomic_flags field before
freeing it.
Fixes: commit 0d73a55208 ("ima: re-introduce own integrity cache lock")
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Aditya Kali <adityakali@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0d73a55208 upstream.
Before IMA appraisal was introduced, IMA was using own integrity cache
lock along with i_mutex. process_measurement and ima_file_free took
the iint->mutex first and then the i_mutex, while setxattr, chmod and
chown took the locks in reverse order. To resolve the potential deadlock,
i_mutex was moved to protect entire IMA functionality and the redundant
iint->mutex was eliminated.
Solution was based on the assumption that filesystem code does not take
i_mutex further. But when file is opened with O_DIRECT flag, direct-io
implementation takes i_mutex and produces deadlock. Furthermore, certain
other filesystem operations, such as llseek, also take i_mutex.
More recently some filesystems have replaced their filesystem specific
lock with the global i_rwsem to read a file. As a result, when IMA
attempts to calculate the file hash, reading the file attempts to take
the i_rwsem again.
To resolve O_DIRECT related deadlock problem, this patch re-introduces
iint->mutex. But to eliminate the original chmod() related deadlock
problem, this patch eliminates the requirement for chmod hooks to take
the iint->mutex by introducing additional atomic iint->attr_flags to
indicate calling of the hooks. The allowed locking order is to take
the iint->mutex first and then the i_rwsem.
Original flags were cleared in chmod(), setxattr() or removwxattr()
hooks and tested when file was closed or opened again. New atomic flags
are set or cleared in those hooks and tested to clear iint->flags on
close or on open.
Atomic flags are following:
* IMA_CHANGE_ATTR - indicates that chATTR() was called (chmod, chown,
chgrp) and file attributes have changed. On file open, it causes IMA
to clear iint->flags to re-evaluate policy and perform IMA functions
again.
* IMA_CHANGE_XATTR - indicates that setxattr or removexattr was called
and extended attributes have changed. On file open, it causes IMA to
clear iint->flags IMA_DONE_MASK to re-appraise.
* IMA_UPDATE_XATTR - indicates that security.ima needs to be updated.
It is cleared if file policy changes and no update is needed.
* IMA_DIGSIG - indicates that file security.ima has signature and file
security.ima must not update to file has on file close.
* IMA_MUST_MEASURE - indicates the file is in the measurement policy.
Fixes: Commit 6552321831 ("xfs: remove i_iolock and use i_rwsem in
the VFS inode instead")
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Aditya Kali <adityakali@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 50b977481f upstream.
The EVM signature includes the inode number and (optionally) the
filesystem UUID, making it impractical to ship EVM signatures in
packages. This patch adds a new portable format intended to allow
distributions to include EVM signatures. It is identical to the existing
format but hardcodes the inode and generation numbers to 0 and does not
include the filesystem UUID even if the kernel is configured to do so.
Removing the inode means that the metadata and signature from one file
could be copied to another file without invalidating it. This is avoided
by ensuring that an IMA xattr is present during EVM validation.
Portable signatures are intended to be immutable - ie, they will never
be transformed into HMACs.
Based on earlier work by Dmitry Kasatkin and Mikhail Kurinnoi.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Cc: Mikhail Kurinnoi <viewizard@viewizard.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Aditya Kali <adityakali@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f3cc6b25dc upstream.
All files matching a "measure" rule must be included in the IMA
measurement list, even when the file hash cannot be calculated.
Similarly, all files matching an "audit" rule must be audited, even when
the file hash can not be calculated.
The file data hash field contained in the IMA measurement list template
data will contain 0's instead of the actual file hash digest.
Note:
In general, adding, deleting or in anyway changing which files are
included in the IMA measurement list is not a good idea, as it might
result in not being able to unseal trusted keys sealed to a specific
TPM PCR value. This patch not only adds file measurements that were
not previously measured, but specifies that the file hash value for
these files will be 0's.
As the IMA measurement list ordering is not consistent from one boot
to the next, it is unlikely that anyone is sealing keys based on the
IMA measurement list. Remote attestation servers should be able to
process these new measurement records, but might complain about
these unknown records.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Cc: Aditya Kali <adityakali@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 19339c2516 upstream.
This reverts commit 0b3c9761d1.
Seth Forshee <seth.forshee@canonical.com> writes:
> All right, I think 0b3c9761d1 should be
> reverted then. EVM is a machine-local integrity mechanism, and so it
> makes sense that the signature would be based on the kernel's notion of
> the uid and not the filesystem's.
I added a commment explaining why the EVM hmac needs to be in the
kernel's notion of uid and gid, not the filesystems to prevent
remounting the filesystem and gaining unwaranted trust in files.
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Aditya Kali <adityakali@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4458bba097 upstream.
syzbot is hitting warning at str_read() [1] because len parameter can
become larger than KMALLOC_MAX_SIZE. We don't need to emit warning for
this case.
[1] https://syzkaller.appspot.com/bug?id=7f2f5aad79ea8663c296a2eedb81978401a908f0
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+ac488b9811036cea7ea0@syzkaller.appspotmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e4c8dafbb upstream.
The 12 character temporary buffer is not necessarily long enough to hold
a 'long' value. Increase it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e2861fa716 ]
When EVM attempts to appraise a file signed with a crypto algorithm the
kernel doesn't have support for, it will cause the kernel to trigger a
module load. If the EVM policy includes appraisal of kernel modules this
will in turn call back into EVM - since EVM is holding a lock until the
crypto initialisation is complete, this triggers a deadlock. Add a
CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag
in the EVM case in order to fail gracefully with an error message
instead of deadlocking.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 129a998909 ]
A socket which has sk_family set to PF_INET6 is able to receive not
only IPv6 but also IPv4 traffic (IPv4-mapped IPv6 addresses).
Prior to this patch, the smk_skb_to_addr_ipv6() could have been
called for socket buffers containing IPv4 packets, in result such
traffic was allowed.
Signed-off-by: Piotr Sawicki <p.sawicki2@partner.samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 476accbe2f upstream.
There is a strange __GFP_NOMEMALLOC usage pattern in SELinux,
specifically GFP_ATOMIC | __GFP_NOMEMALLOC which doesn't make much
sense. GFP_ATOMIC on its own allows to access memory reserves while
__GFP_NOMEMALLOC dictates we cannot use memory reserves. Replace this
with the much more sane GFP_NOWAIT in the AVC code as we can tolerate
memory allocation failures in that code.
Signed-off-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7b4e88434c ]
Smack: Mark inode instant in smack_task_to_inode
/proc clean-up in commit 1bbc55131e
resulted in smack_task_to_inode() being called before smack_d_instantiate.
This resulted in the smk_inode value being ignored, even while present
for files in /proc/self. Marking the inode as instant here fixes that.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit efe3de79e0 upstream.
Call trace:
[<ffffff9203a8d7a8>] dump_backtrace+0x0/0x428
[<ffffff9203a8dbf8>] show_stack+0x28/0x38
[<ffffff920409bfb8>] dump_stack+0xd4/0x124
[<ffffff9203d187e8>] print_address_description+0x68/0x258
[<ffffff9203d18c00>] kasan_report.part.2+0x228/0x2f0
[<ffffff9203d1927c>] kasan_report+0x5c/0x70
[<ffffff9203d1776c>] check_memory_region+0x12c/0x1c0
[<ffffff9203d17cdc>] memcpy+0x34/0x68
[<ffffff9203d75348>] xattr_getsecurity+0xe0/0x160
[<ffffff9203d75490>] vfs_getxattr+0xc8/0x120
[<ffffff9203d75d68>] getxattr+0x100/0x2c8
[<ffffff9203d76fb4>] SyS_fgetxattr+0x64/0xa0
[<ffffff9203a83f70>] el0_svc_naked+0x24/0x28
If user get root access and calls security.selinux setxattr() with an
embedded NUL on a file and then if some process performs a getxattr()
on that file with a length greater than the actual length of the string,
it would result in a panic.
To fix this, add the actual length of the string to the security context
instead of the length passed by the userspace process.
Signed-off-by: Sachin Grover <sgrover@codeaurora.org>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f5acb3dcba upstream.
Userspace applications have been modified to write security xattrs,
but they are not context aware. In the case of security.ima, the
security xattr can be either a file hash or a file signature.
Permitting writing one, but not the other requires the application to
be context aware.
In addition, userspace applications might write files to a staging
area, which might not be in policy, and then change some file metadata
(eg. owner) making it in policy. As a result, these files are not
labeled properly.
This reverts commit c68ed80c97, which
prevents writing file hashes as security.ima xattrs.
Requested-by: Patrick Ohly <patrick.ohly@intel.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 120f3b11ef ]
security/integrity/digsig.c has build errors on some $ARCH due to a
missing header file, so add it.
security/integrity/digsig.c:146:2: error: implicit declaration of function 'vfree' [-Werror=implicit-function-declaration]
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: linux-integrity@vger.kernel.org
Link: http://kisskb.ellerman.id.au/kisskb/head/13396/
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ccb544781d ]
open permission is currently only defined for files in the kernel
(COMMON_FILE_PERMS rather than COMMON_FILE_SOCK_PERMS). Construction of
an artificial test case that tries to open a socket via /proc/pid/fd will
generate a recvfrom avc denial because recvfrom and open happen to map to
the same permission bit in socket vs file classes.
open of a socket via /proc/pid/fd is not supported by the kernel regardless
and will ultimately return ENXIO. But we hit the permission check first and
can thus produce these odd/misleading denials. Omit the open check when
operating on a socket.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 270e857314 upstream.
The check is already performed in ocontext_read() when the policy is
loaded. Removing the array also fixes the following warning when
building with clang:
security/selinux/hooks.c:338:20: error: variable 'labeling_behaviors'
is not needed and will not be emitted
[-Werror,-Wunneeded-internal-declaration]
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 342e91578e upstream.
'perms' will never be NULL since it isn't a plain pointer but an array
of u32 values.
This fixes the following warning when building with clang:
security/selinux/ss/services.c:158:16: error: address of array
'p_in->perms' will always evaluate to 'true'
[-Werror,-Wpointer-bool-conversion]
while (p_in->perms && p_in->perms[k]) {
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b7e27bc1d4 ]
Custom policies can require file signatures based on LSM labels. These
files are normally created and only afterwards labeled, requiring them
to be signed.
Instead of requiring file signatures based on LSM labels, entire
filesystems could require file signatures. In this case, we need the
ability of writing new files without requiring file signatures.
The definition of a "new" file was originally defined as any file with
a length of zero. Subsequent patches redefined a "new" file to be based
on the FILE_CREATE open flag. By combining the open flag with a file
size of zero, this patch relaxes the file signature requirement.
Fixes: 1ac202e978 ima: accept previously set IMA_NEW_FILE
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e2f586bd83 ]
KMSAN (KernelMemorySanitizer, a new error detection tool) reports use of
uninitialized memory in selinux_socket_bind():
==================================================================
BUG: KMSAN: use of unitialized memory
inter: 0
CPU: 3 PID: 1074 Comm: packet2 Tainted: G B 4.8.0-rc6+ #1916
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
0000000000000000 ffff8800882ffb08 ffffffff825759c8 ffff8800882ffa48
ffffffff818bf551 ffffffff85bab870 0000000000000092 ffffffff85bab550
0000000000000000 0000000000000092 00000000bb0009bb 0000000000000002
Call Trace:
[< inline >] __dump_stack lib/dump_stack.c:15
[<ffffffff825759c8>] dump_stack+0x238/0x290 lib/dump_stack.c:51
[<ffffffff818bdee6>] kmsan_report+0x276/0x2e0 mm/kmsan/kmsan.c:1008
[<ffffffff818bf0fb>] __msan_warning+0x5b/0xb0 mm/kmsan/kmsan_instr.c:424
[<ffffffff822dae71>] selinux_socket_bind+0xf41/0x1080 security/selinux/hooks.c:4288
[<ffffffff8229357c>] security_socket_bind+0x1ec/0x240 security/security.c:1240
[<ffffffff84265d98>] SYSC_bind+0x358/0x5f0 net/socket.c:1366
[<ffffffff84265a22>] SyS_bind+0x82/0xa0 net/socket.c:1356
[<ffffffff81005678>] do_syscall_64+0x58/0x70 arch/x86/entry/common.c:292
[<ffffffff8518217c>] entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.o:?
chained origin: 00000000ba6009bb
[<ffffffff810bb7a7>] save_stack_trace+0x27/0x50 arch/x86/kernel/stacktrace.c:67
[< inline >] kmsan_save_stack_with_flags mm/kmsan/kmsan.c:322
[< inline >] kmsan_save_stack mm/kmsan/kmsan.c:337
[<ffffffff818bd2b8>] kmsan_internal_chain_origin+0x118/0x1e0 mm/kmsan/kmsan.c:530
[<ffffffff818bf033>] __msan_set_alloca_origin4+0xc3/0x130 mm/kmsan/kmsan_instr.c:380
[<ffffffff84265b69>] SYSC_bind+0x129/0x5f0 net/socket.c:1356
[<ffffffff84265a22>] SyS_bind+0x82/0xa0 net/socket.c:1356
[<ffffffff81005678>] do_syscall_64+0x58/0x70 arch/x86/entry/common.c:292
[<ffffffff8518217c>] return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.o:?
origin description: ----address@SYSC_bind (origin=00000000b8c00900)
==================================================================
(the line numbers are relative to 4.8-rc6, but the bug persists upstream)
, when I run the following program as root:
=======================================================
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
int main(int argc, char *argv[]) {
struct sockaddr addr;
int size = 0;
if (argc > 1) {
size = atoi(argv[1]);
}
memset(&addr, 0, sizeof(addr));
int fd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
bind(fd, &addr, size);
return 0;
}
=======================================================
(for different values of |size| other error reports are printed).
This happens because bind() unconditionally copies |size| bytes of
|addr| to the kernel, leaving the rest uninitialized. Then
security_socket_bind() reads the IP address bytes, including the
uninitialized ones, to determine the port, or e.g. pass them further to
sel_netnode_find(), which uses them to calculate a hash.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
[PM: fixed some whitespace damage]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3cd18d1981 upstream.
The recent rework introduced a possible randconfig build failure
when CONFIG_CRYPTO configured to only allow modules:
security/keys/big_key.o: In function `big_key_crypt':
big_key.c:(.text+0x29f): undefined reference to `crypto_aead_setkey'
security/keys/big_key.o: In function `big_key_init':
big_key.c:(.init.text+0x1a): undefined reference to `crypto_alloc_aead'
big_key.c:(.init.text+0x45): undefined reference to `crypto_aead_setauthsize'
big_key.c:(.init.text+0x77): undefined reference to `crypto_destroy_tfm'
crypto/gcm.o: In function `gcm_hash_crypt_remain_continue':
gcm.c:(.text+0x167): undefined reference to `crypto_ahash_finup'
crypto/gcm.o: In function `crypto_gcm_exit_tfm':
gcm.c:(.text+0x847): undefined reference to `crypto_destroy_tfm'
When we 'select CRYPTO' like the other users, we always get a
configuration that builds.
Fixes: 428490e38b ("security/keys: rewrite all of big_key crypto")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4b14752ec4 upstream.
We can't do anything reasonable in security_bounded_transition() if we
don't have a policy loaded, and in fact we could run into problems
with some of the code inside expecting a policy. Fix these problems
like we do many others in security/selinux/ss/services.c by checking
to see if the policy is loaded (ss_initialized) and returning quickly
if it isn't.
Reported-by: syzbot <syzkaller-bugs@googlegroups.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ef28df55ac upstream.
The syzbot/syzkaller automated tests found a problem in
security_context_to_sid_core() during early boot (before we load the
SELinux policy) where we could potentially feed context strings without
NUL terminators into the strcmp() function.
We already guard against this during normal operation (after the SELinux
policy has been loaded) by making a copy of the context strings and
explicitly adding a NUL terminator to the end. The patch extends this
protection to the early boot case (no loaded policy) by moving the context
copy earlier in security_context_to_sid_core().
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reviewed-By: William Roberts <william.c.roberts@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 794b4bc292 upstream.
With the 'encrypted' key type it was possible for userspace to provide a
data blob ending with a master key description shorter than expected,
e.g. 'keyctl add encrypted desc "new x" @s'. When validating such a
master key description, validate_master_desc() could read beyond the end
of the buffer. Fix this by using strncmp() instead of memcmp(). [Also
clean up the code to deduplicate some logic.]
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Jin Qian <jinqian@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the required bits have been addressed, reenable
PARAVIRT.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We fail to see what CONFIG_KAISER_REAL_SWITCH is for: it seems to be
left over from early development, and now just obscures tricky parts
of the code. Delete it before adding PCIDs, or nokaiser boot option.
(Or if there is some good reason to keep the option, then it needs
a help text - and a "depends on KAISER", so that all those without
KAISER are not asked the question. But we'd much rather delete it.)
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is absurd that KAISER should depend on SMP, but apparently nobody
has tried a UP build before: which breaks on implicit declaration of
function 'per_cpu_offset' in arch/x86/mm/kaiser.c.
Now, you would expect that to be trivially fixed up; but looking at
the System.map when that block is #ifdef'ed out of kaiser_init(),
I see that in a UP build __per_cpu_user_mapped_end is precisely at
__per_cpu_user_mapped_start, and the items carefully gathered into
that section for user-mapping on SMP, dispersed elsewhere on UP.
So, some other kind of section assignment will be needed on UP,
but implementing that is not a priority: just make KAISER depend
on SMP for now.
Also inserted a blank line before the option, tidied up the
brief Kconfig help message, and added an "If unsure, Y".
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merged fixes and cleanups, rebased to 4.9.51 tree (no 5-level paging).
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces our implementation of KAISER (Kernel Address Isolation to
have Side-channels Efficiently Removed), a kernel isolation technique to close
hardware side channels on kernel address information.
More information about the patch can be found on:
https://github.com/IAIK/KAISER
From: Richard Fellner <richard.fellner@student.tugraz.at>
From: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Subject: [RFC, PATCH] x86_64: KAISER - do not map kernel in user mode
Date: Thu, 4 May 2017 14:26:50 +0200
Link: http://marc.info/?l=linux-kernel&m=149390087310405&w=2
Kaiser-4.10-SHA1: c4b1831d44c6144d3762ccc72f0c4e71a0c713e5
To: <linux-kernel@vger.kernel.org>
To: <kernel-hardening@lists.openwall.com>
Cc: <clementine.maurice@iaik.tugraz.at>
Cc: <moritz.lipp@iaik.tugraz.at>
Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Cc: Richard Fellner <richard.fellner@student.tugraz.at>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <kirill.shutemov@linux.intel.com>
Cc: <anders.fogh@gdata-adan.de>
After several recent works [1,2,3] KASLR on x86_64 was basically
considered dead by many researchers. We have been working on an
efficient but effective fix for this problem and found that not mapping
the kernel space when running in user mode is the solution to this
problem [4] (the corresponding paper [5] will be presented at ESSoS17).
With this RFC patch we allow anybody to configure their kernel with the
flag CONFIG_KAISER to add our defense mechanism.
If there are any questions we would love to answer them.
We also appreciate any comments!
Cheers,
Daniel (+ the KAISER team from Graz University of Technology)
[1] http://www.ieee-security.org/TC/SP2013/papers/4977a191.pdf
[2] https://www.blackhat.com/docs/us-16/materials/us-16-Fogh-Using-Undocumented-CPU-Behaviour-To-See-Into-Kernel-Mode-And-Break-KASLR-In-The-Process.pdf
[3] https://www.blackhat.com/docs/us-16/materials/us-16-Jang-Breaking-Kernel-Address-Space-Layout-Randomization-KASLR-With-Intel-TSX.pdf
[4] https://github.com/IAIK/KAISER
[5] https://gruss.cc/files/kaiser.pdf
[patch based also on
https://raw.githubusercontent.com/IAIK/KAISER/master/KAISER/0001-KAISER-Kernel-Address-Isolation.patch]
Signed-off-by: Richard Fellner <richard.fellner@student.tugraz.at>
Signed-off-by: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
Signed-off-by: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Signed-off-by: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4dca6ea1d9 upstream.
When the request_key() syscall is not passed a destination keyring, it
links the requested key (if constructed) into the "default" request-key
keyring. This should require Write permission to the keyring. However,
there is actually no permission check.
This can be abused to add keys to any keyring to which only Search
permission is granted. This is because Search permission allows joining
the keyring. keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_SESSION_KEYRING)
then will set the default request-key keyring to the session keyring.
Then, request_key() can be used to add keys to the keyring.
Both negatively and positively instantiated keys can be added using this
method. Adding negative keys is trivial. Adding a positive key is a
bit trickier. It requires that either /sbin/request-key positively
instantiates the key, or that another thread adds the key to the process
keyring at just the right time, such that request_key() misses it
initially but then finds it in construct_alloc_key().
Fix this bug by checking for Write permission to the keyring in
construct_get_dest_keyring() when the default keyring is being used.
We don't do the permission check for non-default keyrings because that
was already done by the earlier call to lookup_user_key(). Also,
request_key_and_link() is currently passed a 'struct key *' rather than
a key_ref_t, so the "possessed" bit is unavailable.
We also don't do the permission check for the "requestor keyring", to
continue to support the use case described by commit 8bbf4976b5
("KEYS: Alter use of key instantiation link-to-keyring argument") where
/sbin/request-key recursively calls request_key() to add keys to the
original requestor's destination keyring. (I don't know of any users
who actually do that, though...)
Fixes: 3e30148c3d ("[PATCH] Keys: Make request-key create an authorisation key")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ebe7c0a7be ]
The hash_setup function always sets the hash_setup_done flag, even
when the hash algorithm is invalid. This prevents the default hash
algorithm defined as CONFIG_IMA_DEFAULT_HASH from being used.
This patch sets hash_setup_done flag only for valid hash algorithms.
Fixes: e7a2ad7eb6 "ima: enable support for larger default filedata hash algorithms"
Signed-off-by: Boshi Wang <wangboshi@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 020aae3ee5 upstream.
Commit b65a9cfc2c ("Untangling ima mess, part 2: deal with counters")
moved the call of ima_file_check() from may_open() to do_filp_open() at a
point where the file descriptor is already opened.
This breaks the assumption made by IMA that file descriptors being closed
belong to files whose access was granted by ima_file_check(). The
consequence is that security.ima and security.evm are updated with good
values, regardless of the current appraisal status.
For example, if a file does not have security.ima, IMA will create it after
opening the file for writing, even if access is denied. Access to the file
will be allowed afterwards.
Avoid this issue by checking the appraisal status before updating
security.ima.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 47b2c3fff4 upstream.
CONFIG_KEYS_COMPAT is defined in arch-specific Kconfigs and is missing for
several 64-bit architectures : mips, parisc, tile.
At the moment and for those architectures, calling in 32-bit userspace the
keyctl syscall would return an ENOSYS error.
This patch moves the CONFIG_KEYS_COMPAT option to security/keys/Kconfig, to
make sure the compatibility wrapper is registered by default for any 64-bit
architecture as long as it is configured with CONFIG_COMPAT.
[DH: Modified to remove arm64 compat enablement also as requested by Eric
Biggers]
Signed-off-by: Bilal Amarni <bilal.amarni@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
cc: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Cc: James Cowgill <james.cowgill@mips.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a3c812f7cf upstream.
When calling keyctl_read() on a key of type "trusted", if the
user-supplied buffer was too small, the kernel ignored the buffer length
and just wrote past the end of the buffer, potentially corrupting
userspace memory. Fix it by instead returning the size required, as per
the documentation for keyctl_read().
We also don't even fill the buffer at all in this case, as this is
slightly easier to implement than doing a short read, and either
behavior appears to be permitted. It also makes it match the behavior
of the "encrypted" key type.
Fixes: d00a1c72f7 ("keys: add new trusted key-type")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee618b4619 upstream.
As the previous patch did for encrypted-keys, zero sensitive any
potentially sensitive data related to the "trusted" key type before it
is freed. Notably, we were not zeroing the tpm_buf structures in which
the actual key is stored for TPM seal and unseal, nor were we zeroing
the trusted_key_payload in certain error paths.
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Safford <safford@us.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3ccb76c5df ]
The kernel build bot turned up a bad config combination when
CONFIG_SECURITY_APPARMOR is y and CONFIG_SECURITY_APPARMOR_HASH is n,
resulting in the build error
security/built-in.o: In function `aa_unpack':
(.text+0x841e2): undefined reference to `aa_g_hash_policy'
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3239b6f29b upstream.
Commit e645016abc ("KEYS: fix writing past end of user-supplied buffer
in keyring_read()") made keyring_read() stop corrupting userspace memory
when the user-supplied buffer is too small. However it also made the
return value in that case be the short buffer size rather than the size
required, yet keyctl_read() is actually documented to return the size
required. Therefore, switch it over to the documented behavior.
Note that for now we continue to have it fill the short buffer, since it
did that before (pre-v3.13) and dump_key_tree_aux() in keyutils arguably
relies on it.
Fixes: e645016abc ("KEYS: fix writing past end of user-supplied buffer in keyring_read()")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 363b02dab0 upstream.
Consolidate KEY_FLAG_INSTANTIATED, KEY_FLAG_NEGATIVE and the rejection
error into one field such that:
(1) The instantiation state can be modified/read atomically.
(2) The error can be accessed atomically with the state.
(3) The error isn't stored unioned with the payload pointers.
This deals with the problem that the state is spread over three different
objects (two bits and a separate variable) and reading or updating them
atomically isn't practical, given that not only can uninstantiated keys
change into instantiated or rejected keys, but rejected keys can also turn
into instantiated keys - and someone accessing the key might not be using
any locking.
The main side effect of this problem is that what was held in the payload
may change, depending on the state. For instance, you might observe the
key to be in the rejected state. You then read the cached error, but if
the key semaphore wasn't locked, the key might've become instantiated
between the two reads - and you might now have something in hand that isn't
actually an error code.
The state is now KEY_IS_UNINSTANTIATED, KEY_IS_POSITIVE or a negative error
code if the key is negatively instantiated. The key_is_instantiated()
function is replaced with key_is_positive() to avoid confusion as negative
keys are also 'instantiated'.
Additionally, barriering is included:
(1) Order payload-set before state-set during instantiation.
(2) Order state-read before payload-read when using the key.
Further separate barriering is necessary if RCU is being used to access the
payload content after reading the payload pointers.
Fixes: 146aa8b145 ("KEYS: Merge the type-specific data with the payload data")
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Al Viro