linux.git/security, branch v4.19.59 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git apparmor: enforce nullbyte at end of tag string 2019-06-25T03:35:54+00:00 Jann Horn jannh@google.com 2019-05-28T15:32:26+00:00 31c99580687ac35a973b7bbc8fff20236540e2e5 commit 8404d7a674c49278607d19726e0acc0cae299357 upstream. A packed AppArmor policy contains null-terminated tag strings that are read by unpack_nameX(). However, unpack_nameX() uses string functions on them without ensuring that they are actually null-terminated, potentially leading to out-of-bounds accesses. Make sure that the tag string is null-terminated before passing it to strcmp(). Cc: stable@vger.kernel.org Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8404d7a674c49278607d19726e0acc0cae299357 upstream.

A packed AppArmor policy contains null-terminated tag strings that are read
by unpack_nameX(). However, unpack_nameX() uses string functions on them
without ensuring that they are actually null-terminated, potentially
leading to out-of-bounds accesses.

Make sure that the tag string is null-terminated before passing it to
strcmp().

Cc: stable@vger.kernel.org
Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
apparmor: fix PROFILE_MEDIATES for untrusted input 2019-06-25T03:35:54+00:00 John Johansen john.johansen@canonical.com 2019-05-26T13:42:23+00:00 eb2b0bf5c4a4afc4a761550af1da7da8444803b8 commit 23375b13f98c5464c2b4d15f983cc062940f1f4e upstream. While commit 11c236b89d7c2 ("apparmor: add a default null dfa") ensure every profile has a policy.dfa it does not resize the policy.start[] to have entries for every possible start value. Which means PROFILE_MEDIATES is not safe to use on untrusted input. Unforunately commit b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE") did not take into account the start value usage. The input string in profile_query_cb() is user controlled and is not properly checked to be within the limited start[] entries, even worse it can't be as userspace policy is allowed to make us of entries types the kernel does not know about. This mean usespace can currently cause the kernel to access memory up to 240 entries beyond the start array bounds. Cc: stable@vger.kernel.org Fixes: b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE") Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 23375b13f98c5464c2b4d15f983cc062940f1f4e upstream.

While commit 11c236b89d7c2 ("apparmor: add a default null dfa") ensure
every profile has a policy.dfa it does not resize the policy.start[]
to have entries for every possible start value. Which means
PROFILE_MEDIATES is not safe to use on untrusted input. Unforunately
commit b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE") did not
take into account the start value usage.

The input string in profile_query_cb() is user controlled and is not
properly checked to be within the limited start[] entries, even worse
it can't be as userspace policy is allowed to make us of entries types
the kernel does not know about. This mean usespace can currently cause
the kernel to access memory up to 240 entries beyond the start array
bounds.

Cc: stable@vger.kernel.org
Fixes: b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
evm: check hash algorithm passed to init_desc() 2019-06-09T07:17:21+00:00 Roberto Sassu roberto.sassu@huawei.com 2019-05-29T13:30:33+00:00 6e322a9e42cd9099121e786b326bc840ac28b5e0 commit 221be106d75c1b511973301542f47d6000d0b63e upstream. This patch prevents memory access beyond the evm_tfm array by checking the validity of the index (hash algorithm) passed to init_desc(). The hash algorithm can be arbitrarily set if the security.ima xattr type is not EVM_XATTR_HMAC. Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 221be106d75c1b511973301542f47d6000d0b63e upstream.

This patch prevents memory access beyond the evm_tfm array by checking the
validity of the index (hash algorithm) passed to init_desc(). The hash
algorithm can be arbitrarily set if the security.ima xattr type is not
EVM_XATTR_HMAC.

Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ima: show rules with IMA_INMASK correctly 2019-06-09T07:17:21+00:00 Roberto Sassu roberto.sassu@huawei.com 2019-05-29T13:30:35+00:00 f85b87a9a2a8bdd2eee28a378a7124d775800122 commit 8cdc23a3d9ec0944000ad43bad588e36afdc38cd upstream. Show the '^' character when a policy rule has flag IMA_INMASK. Fixes: 80eae209d63ac ("IMA: allow reading back the current IMA policy") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8cdc23a3d9ec0944000ad43bad588e36afdc38cd upstream.

Show the '^' character when a policy rule has flag IMA_INMASK.

Fixes: 80eae209d63ac ("IMA: allow reading back the current IMA policy")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
selinux: avoid uninitialized variable warning 2019-05-31T13:46:31+00:00 Arnd Bergmann arnd@arndb.de 2019-03-25T14:23:11+00:00 a2ace9b243878ab2c3392a08df47faaca1edaf14 [ Upstream commit 98bbbb76f2edcfb8fb2b8f4b3ccc7b6e99d64bd8 ] clang correctly points out a code path that would lead to an uninitialized variable use: security/selinux/netlabel.c:310:6: error: variable 'addr' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] if (ip_hdr(skb)->version == 4) { ^~~~~~~~~~~~~~~~~~~~~~~~~ security/selinux/netlabel.c:322:40: note: uninitialized use occurs here rc = netlbl_conn_setattr(ep->base.sk, addr, &secattr); ^~~~ security/selinux/netlabel.c:310:2: note: remove the 'if' if its condition is always true if (ip_hdr(skb)->version == 4) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ security/selinux/netlabel.c:291:23: note: initialize the variable 'addr' to silence this warning struct sockaddr *addr; ^ = NULL This is probably harmless since we should not see ipv6 packets of CONFIG_IPV6 is disabled, but it's better to rearrange the code so this cannot happen. Signed-off-by: Arnd Bergmann <arnd@arndb.de> [PM: removed old patchwork link, fixed checkpatch.pl style errors] Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 98bbbb76f2edcfb8fb2b8f4b3ccc7b6e99d64bd8 ]

clang correctly points out a code path that would lead
to an uninitialized variable use:

security/selinux/netlabel.c:310:6: error: variable 'addr' is used uninitialized whenever 'if' condition is false
      [-Werror,-Wsometimes-uninitialized]
        if (ip_hdr(skb)->version == 4) {
            ^~~~~~~~~~~~~~~~~~~~~~~~~
security/selinux/netlabel.c:322:40: note: uninitialized use occurs here
        rc = netlbl_conn_setattr(ep->base.sk, addr, &secattr);
                                              ^~~~
security/selinux/netlabel.c:310:2: note: remove the 'if' if its condition is always true
        if (ip_hdr(skb)->version == 4) {
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
security/selinux/netlabel.c:291:23: note: initialize the variable 'addr' to silence this warning
        struct sockaddr *addr;
                             ^
                              = NULL

This is probably harmless since we should not see ipv6 packets
of CONFIG_IPV6 is disabled, but it's better to rearrange the code
so this cannot happen.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[PM: removed old patchwork link, fixed checkpatch.pl style errors]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
apparmorfs: fix use-after-free on symlink traversal 2019-05-25T16:23:42+00:00 Al Viro viro@zeniv.linux.org.uk 2019-04-10T18:04:34+00:00 b21ca2769b0f79840749674b98b3e3b7f5730e17 [ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ] symlink body shouldn't be freed without an RCU delay. Switch apparmorfs to ->destroy_inode() and use of call_rcu(); free both the inode and symlink body in the callback. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ]

symlink body shouldn't be freed without an RCU delay.  Switch apparmorfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
securityfs: fix use-after-free on symlink traversal 2019-05-25T16:23:42+00:00 Al Viro viro@zeniv.linux.org.uk 2019-04-10T18:03:45+00:00 9a0467e1f67155c126e5857b1d3ae2ac8b009aa5 [ Upstream commit 46c874419652bbefdfed17420fd6e88d8a31d9ec ] symlink body shouldn't be freed without an RCU delay. Switch securityfs to ->destroy_inode() and use of call_rcu(); free both the inode and symlink body in the callback. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 46c874419652bbefdfed17420fd6e88d8a31d9ec ]

symlink body shouldn't be freed without an RCU delay.  Switch securityfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
selinux: do not report error on connect(AF_UNSPEC) 2019-05-16T17:41:30+00:00 Paolo Abeni pabeni@redhat.com 2019-05-08T13:32:51+00:00 dfdfad3d188f6c524c06b469d3bbfe6af5004f71 [ Upstream commit c7e0d6cca86581092cbbf2cd868b3601495554cf ] calling connect(AF_UNSPEC) on an already connected TCP socket is an established way to disconnect() such socket. After commit 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure") it no longer works and, in the above scenario connect() fails with EAFNOSUPPORT. Fix the above falling back to the generic/old code when the address family is not AF_INET{4,6}, but leave the SCTP code path untouched, as it has specific constraints. Fixes: 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure") Reported-by: Tom Deseyn <tdeseyn@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit c7e0d6cca86581092cbbf2cd868b3601495554cf ]

calling connect(AF_UNSPEC) on an already connected TCP socket is an
established way to disconnect() such socket. After commit 68741a8adab9
("selinux: Fix ltp test connect-syscall failure") it no longer works
and, in the above scenario connect() fails with EAFNOSUPPORT.

Fix the above falling back to the generic/old code when the address family
is not AF_INET{4,6}, but leave the SCTP code path untouched, as it has
specific constraints.

Fixes: 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure")
Reported-by: Tom Deseyn <tdeseyn@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
selinux: never allow relabeling on context mounts 2019-05-08T05:21:54+00:00 Ondrej Mosnacek omosnace@redhat.com 2018-12-21T20:18:52+00:00 574be221407e4f4780c413a87f1fc27dea86995f commit a83d6ddaebe541570291205cb538e35ad4ff94f9 upstream. In the SECURITY_FS_USE_MNTPOINT case we never want to allow relabeling files/directories, so we should never set the SBLABEL_MNT flag. The 'special handling' in selinux_is_sblabel_mnt() is only intended for when the behavior is set to SECURITY_FS_USE_GENFS. While there, make the logic in selinux_is_sblabel_mnt() more explicit and add a BUILD_BUG_ON() to make sure that introducing a new SECURITY_FS_USE_* forces a review of the logic. Fixes: d5f3a5f6e7e7 ("selinux: add security in-core xattr support for pstore and debugfs") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-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 a83d6ddaebe541570291205cb538e35ad4ff94f9 upstream.

In the SECURITY_FS_USE_MNTPOINT case we never want to allow relabeling
files/directories, so we should never set the SBLABEL_MNT flag. The
'special handling' in selinux_is_sblabel_mnt() is only intended for when
the behavior is set to SECURITY_FS_USE_GENFS.

While there, make the logic in selinux_is_sblabel_mnt() more explicit
and add a BUILD_BUG_ON() to make sure that introducing a new
SECURITY_FS_USE_* forces a review of the logic.

Fixes: d5f3a5f6e7e7 ("selinux: add security in-core xattr support for pstore and debugfs")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-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>
selinux: avoid silent denials in permissive mode under RCU walk 2019-05-08T05:21:54+00:00 Stephen Smalley sds@tycho.nsa.gov 2018-12-12T15:10:55+00:00 6b13ae52ac75da7970fde9d08c495a5671605473 commit 3a28cff3bd4bf43f02be0c4e7933aebf3dc8197e upstream. commit 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe") results in no audit messages at all if in permissive mode because the cache is updated during the rcu walk and thus no denial occurs on the subsequent ref walk. Fix this by not updating the cache when performing a non-blocking permission check. This only affects search and symlink read checks during rcu walk. Fixes: 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe") Reported-by: BMK <bmktuwien@gmail.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 3a28cff3bd4bf43f02be0c4e7933aebf3dc8197e upstream.

commit 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe")
results in no audit messages at all if in permissive mode because the
cache is updated during the rcu walk and thus no denial occurs on
the subsequent ref walk.  Fix this by not updating the cache when
performing a non-blocking permission check.  This only affects search
and symlink read checks during rcu walk.

Fixes: 0dc1ba24f7fff6 ("SELINUX: Make selinux cache VFS RCU walks safe")
Reported-by: BMK <bmktuwien@gmail.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>