linux-stable.git/security/integrity/integrity.h, branch linux-3.16.y Linux kernel stable tree ima: check xattr value length and type in the ima_inode_setxattr() 2014-11-13T11:48:50+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2014-10-28T11:31:22+00:00 2b94fbb8a5cc34e4ad8a6b547a31b23a7d88aa48 commit a48fda9de94500a3152a56b723d0a64ae236547c upstream. ima_inode_setxattr() can be called with no value. Function does not check the length so that following command can be used to produce kernel oops: setfattr -n security.ima FOO. This patch fixes it. Changes in v3: * for stable reverted "allow setting hash only in fix or log mode" It will be a separate patch. Changes in v2: * testing validity of xattr type * allow setting hash only in fix or log mode (Mimi) [ 261.562522] BUG: unable to handle kernel NULL pointer dereference at (null) [ 261.564109] IP: [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] PGD 3112f067 PUD 42965067 PMD 0 [ 261.564109] Oops: 0000 [#1] SMP [ 261.564109] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse [ 261.564109] CPU: 0 PID: 3299 Comm: setxattr Not tainted 3.16.0-kds+ #2924 [ 261.564109] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 261.564109] task: ffff8800428c2430 ti: ffff880042be0000 task.ti: ffff880042be0000 [ 261.564109] RIP: 0010:[<ffffffff812af272>] [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] RSP: 0018:ffff880042be3d50 EFLAGS: 00010246 [ 261.564109] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000015 [ 261.564109] RDX: 0000001500000000 RSI: 0000000000000000 RDI: ffff8800375cc600 [ 261.564109] RBP: ffff880042be3d68 R08: 0000000000000000 R09: 00000000004d6256 [ 261.564109] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88002149ba00 [ 261.564109] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 261.564109] FS: 00007f6c1e219740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000 [ 261.564109] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 261.564109] CR2: 0000000000000000 CR3: 000000003b35a000 CR4: 00000000000006f0 [ 261.564109] Stack: [ 261.564109] ffff88002149ba00 ffff880042be3df8 0000000000000000 ffff880042be3d98 [ 261.564109] ffffffff812a101b ffff88002149ba00 ffff880042be3df8 0000000000000000 [ 261.564109] 0000000000000000 ffff880042be3de0 ffffffff8116d08a ffff880042be3dc8 [ 261.564109] Call Trace: [ 261.564109] [<ffffffff812a101b>] security_inode_setxattr+0x48/0x6a [ 261.564109] [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f [ 261.564109] [<ffffffff8116d1e0>] setxattr+0x122/0x16c [ 261.564109] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 261.564109] [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143 [ 261.564109] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 261.564109] [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f [ 261.564109] [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0 [ 261.564109] [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b [ 261.564109] Code: 48 89 f7 48 c7 c6 58 36 81 81 53 31 db e8 73 27 04 00 85 c0 75 28 bf 15 00 00 00 e8 8a a5 d9 ff 84 c0 75 05 83 cb ff eb 15 31 f6 <41> 80 7d 00 03 49 8b 7c 24 68 40 0f 94 c6 e8 e1 f9 ff ff 89 d8 [ 261.564109] RIP [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a [ 261.564109] RSP <ffff880042be3d50> [ 261.564109] CR2: 0000000000000000 [ 261.599998] ---[ end trace 39a89a3fc267e652 ]--- Reported-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> 
commit a48fda9de94500a3152a56b723d0a64ae236547c upstream.

ima_inode_setxattr() can be called with no value. Function does not
check the length so that following command can be used to produce
kernel oops: setfattr -n security.ima FOO. This patch fixes it.

Changes in v3:
* for stable reverted "allow setting hash only in fix or log mode"
  It will be a separate patch.

Changes in v2:
* testing validity of xattr type
* allow setting hash only in fix or log mode (Mimi)

[  261.562522] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  261.564109] IP: [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109] PGD 3112f067 PUD 42965067 PMD 0
[  261.564109] Oops: 0000 [#1] SMP
[  261.564109] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse
[  261.564109] CPU: 0 PID: 3299 Comm: setxattr Not tainted 3.16.0-kds+ #2924
[  261.564109] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  261.564109] task: ffff8800428c2430 ti: ffff880042be0000 task.ti: ffff880042be0000
[  261.564109] RIP: 0010:[<ffffffff812af272>]  [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109] RSP: 0018:ffff880042be3d50  EFLAGS: 00010246
[  261.564109] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000015
[  261.564109] RDX: 0000001500000000 RSI: 0000000000000000 RDI: ffff8800375cc600
[  261.564109] RBP: ffff880042be3d68 R08: 0000000000000000 R09: 00000000004d6256
[  261.564109] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88002149ba00
[  261.564109] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  261.564109] FS:  00007f6c1e219740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000
[  261.564109] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  261.564109] CR2: 0000000000000000 CR3: 000000003b35a000 CR4: 00000000000006f0
[  261.564109] Stack:
[  261.564109]  ffff88002149ba00 ffff880042be3df8 0000000000000000 ffff880042be3d98
[  261.564109]  ffffffff812a101b ffff88002149ba00 ffff880042be3df8 0000000000000000
[  261.564109]  0000000000000000 ffff880042be3de0 ffffffff8116d08a ffff880042be3dc8
[  261.564109] Call Trace:
[  261.564109]  [<ffffffff812a101b>] security_inode_setxattr+0x48/0x6a
[  261.564109]  [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f
[  261.564109]  [<ffffffff8116d1e0>] setxattr+0x122/0x16c
[  261.564109]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
[  261.564109]  [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143
[  261.564109]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
[  261.564109]  [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f
[  261.564109]  [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0
[  261.564109]  [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b
[  261.564109] Code: 48 89 f7 48 c7 c6 58 36 81 81 53 31 db e8 73 27 04 00 85 c0 75 28 bf 15 00 00 00 e8 8a a5 d9 ff 84 c0 75 05 83 cb ff eb 15 31 f6 <41> 80 7d 00 03 49 8b 7c 24 68 40 0f 94 c6 e8 e1 f9 ff ff 89 d8
[  261.564109] RIP  [<ffffffff812af272>] ima_inode_setxattr+0x3e/0x5a
[  261.564109]  RSP <ffff880042be3d50>
[  261.564109] CR2: 0000000000000000
[  261.599998] ---[ end trace 39a89a3fc267e652 ]---

Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
ima: provide flag to identify new empty files 2014-10-30T16:40:16+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2014-06-27T15:04:27+00:00 88a111df23ba853ff85592dbc512a5aa8a348c50 commit b151d6b00bbb798c58f2f21305e7d43fa763f34f upstream. On ima_file_free(), newly created empty files are not labeled with an initial security.ima value, because the iversion did not change. Commit dff6efc "fs: fix iversion handling" introduced a change in iversion behavior. To verify this change use the shell command: $ (exec >foo) $ getfattr -h -e hex -d -m security foo This patch defines the IMA_NEW_FILE flag. The flag is initially set, when IMA detects that a new file is created, and subsequently checked on the ima_file_free() hook to set the initial security.ima value. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b151d6b00bbb798c58f2f21305e7d43fa763f34f upstream.

On ima_file_free(), newly created empty files are not labeled with
an initial security.ima value, because the iversion did not change.
Commit dff6efc "fs: fix iversion handling" introduced a change in
iversion behavior.  To verify this change use the shell command:

  $ (exec >foo)
  $ getfattr -h -e hex -d -m security foo

This patch defines the IMA_NEW_FILE flag.  The flag is initially
set, when IMA detects that a new file is created, and subsequently
checked on the ima_file_free() hook to set the initial security.ima
value.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ima: audit log files opened with O_DIRECT flag 2014-06-03T19:21:50+00:00 Mimi Zohar zohar@linux.vnet.ibm.com 2014-05-12T13:28:11+00:00 f9b2a735bdddf836214b5dca74f6ca7712e5a08c Files are measured or appraised based on the IMA policy. When a file, in policy, is opened with the O_DIRECT flag, a deadlock occurs. The first attempt at resolving this lockdep temporarily removed the O_DIRECT flag and restored it, after calculating the hash. The second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this flag, do_blockdev_direct_IO() would skip taking the i_mutex a second time. The third attempt, by Dmitry Kasatkin, resolves the i_mutex locking issue, by re-introducing the IMA mutex, but uncovered another problem. Reading a file with O_DIRECT flag set, writes directly to userspace pages. A second patch allocates a user-space like memory. This works for all IMA hooks, except ima_file_free(), which is called on __fput() to recalculate the file hash. Until this last issue is addressed, do not 'collect' the measurement for measuring, appraising, or auditing files opened with the O_DIRECT flag set. Based on policy, permit or deny file access. This patch defines a new IMA policy rule option named 'permit_directio'. Policy rules could be defined, based on LSM or other criteria, to permit specific applications to open files with the O_DIRECT flag set. Changelog v1: - permit or deny file access based IMA policy rules Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Cc: <stable@vger.kernel.org> 
Files are measured or appraised based on the IMA policy.  When a
file, in policy, is opened with the O_DIRECT flag, a deadlock
occurs.

The first attempt at resolving this lockdep temporarily removed the
O_DIRECT flag and restored it, after calculating the hash.  The
second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this
flag, do_blockdev_direct_IO() would skip taking the i_mutex a second
time.  The third attempt, by Dmitry Kasatkin, resolves the i_mutex
locking issue, by re-introducing the IMA mutex, but uncovered
another problem.  Reading a file with O_DIRECT flag set, writes
directly to userspace pages.  A second patch allocates a user-space
like memory.  This works for all IMA hooks, except ima_file_free(),
which is called on __fput() to recalculate the file hash.

Until this last issue is addressed, do not 'collect' the
measurement for measuring, appraising, or auditing files opened
with the O_DIRECT flag set.  Based on policy, permit or deny file
access.  This patch defines a new IMA policy rule option named
'permit_directio'.  Policy rules could be defined, based on LSM
or other criteria, to permit specific applications to open files
with the O_DIRECT flag set.

Changelog v1:
- permit or deny file access based IMA policy rules

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: <stable@vger.kernel.org>
Revert "ima: define '_ima' as a builtin 'trusted' keyring" 2013-11-24T00:36:35+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-11-24T00:36:35+00:00 34ef7bd3823bf4401bf8f1f855e1bc77b82b1a43 This reverts commit 217091dd7a7a1bdac027ddb7c5a25f6ac0b8e241, which caused the following build error: security/integrity/digsig.c:70:5: error: redefinition of ‘integrity_init_keyring’ security/integrity/integrity.h:149:12: note: previous definition of ‘integrity_init_keyring’ w security/integrity/integrity.h:149:12: warning: ‘integrity_init_keyring’ defined but not used reported by Krzysztof Kolasa. Mimi says: "I made the classic mistake of requesting this patch to be upstreamed at the last second, rather than waiting until the next open window. At this point, the best course would probably be to revert the two commits and fix them for the next open window" Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This reverts commit 217091dd7a7a1bdac027ddb7c5a25f6ac0b8e241, which
caused the following build error:

  security/integrity/digsig.c:70:5: error: redefinition of ‘integrity_init_keyring’
  security/integrity/integrity.h:149:12: note: previous definition of ‘integrity_init_keyring’ w
  security/integrity/integrity.h:149:12: warning: ‘integrity_init_keyring’ defined but not used

reported by Krzysztof Kolasa. Mimi says:

 "I made the classic mistake of requesting this patch to be upstreamed
  at the last second, rather than waiting until the next open window.

  At this point, the best course would probably be to revert the two
  commits and fix them for the next open window"

Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ima: define '_ima' as a builtin 'trusted' keyring 2013-11-01T00:20:48+00:00 Mimi Zohar zohar@linux.vnet.ibm.com 2013-08-13T12:47:43+00:00 217091dd7a7a1bdac027ddb7c5a25f6ac0b8e241 Require all keys added to the IMA keyring be signed by an existing trusted key on the system trusted keyring. Changelog: - define stub integrity_init_keyring() function (reported-by Fengguang Wu) - differentiate between regular and trusted keyring names. - replace printk with pr_info (D. Kasatkin) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> 
Require all keys added to the IMA keyring be signed by an
existing trusted key on the system trusted keyring.

Changelog:
- define stub integrity_init_keyring() function (reported-by Fengguang Wu)
- differentiate between regular and trusted keyring names.
- replace printk with pr_info (D. Kasatkin)

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
ima: provide hash algo info in the xattr 2013-10-27T01:32:55+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2013-08-12T08:22:51+00:00 3ea7a56067e663278470c04fd655adf809e72d4d All files labeled with 'security.ima' hashes, are hashed using the same hash algorithm. Changing from one hash algorithm to another, requires relabeling the filesystem. This patch defines a new xattr type, which includes the hash algorithm, permitting different files to be hashed with different algorithms. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> 
All files labeled with 'security.ima' hashes, are hashed using the
same hash algorithm.  Changing from one hash algorithm to another,
requires relabeling the filesystem.  This patch defines a new xattr
type, which includes the hash algorithm, permitting different files
to be hashed with different algorithms.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima: use dynamically allocated hash storage 2013-10-25T21:17:00+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2013-04-25T07:44:04+00:00 a35c3fb6490cc1d3446e4781693408100113c4fb For each inode in the IMA policy, an iint is allocated. To support larger hash digests, the iint digest size changed from 20 bytes to the maximum supported hash digest size. Instead of allocating the maximum size, which most likely is not needed, this patch dynamically allocates the needed hash storage. Changelog: - fix krealloc bug Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> 
For each inode in the IMA policy, an iint is allocated.  To support
larger hash digests, the iint digest size changed from 20 bytes to
the maximum supported hash digest size.  Instead of allocating the
maximum size, which most likely is not needed, this patch dynamically
allocates the needed hash storage.

Changelog:
- fix krealloc bug

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima: pass full xattr with the signature 2013-10-25T21:16:59+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2013-10-10T07:12:03+00:00 b1aaab22e263d0cca1effe319b7d2bf895444219 For possibility to use xattr type for new signature formats, pass full xattr to the signature verification function. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> 
For possibility to use xattr type for new signature formats,
pass full xattr to the signature verification function.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima: read and use signature hash algorithm 2013-10-25T21:16:59+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2013-04-25T07:44:04+00:00 d3634d0f426bdeb433cb288bdbb0a5e16cf3dbbf All files on the filesystem, currently, are hashed using the same hash algorithm. In preparation for files from different packages being signed using different hash algorithms, this patch adds support for reading the signature hash algorithm from the 'security.ima' extended attribute and calculates the appropriate file data hash based on it. Changelog: - fix scripts Lindent and checkpatch msgs - Mimi - fix md5 support for older version, which occupied 20 bytes in the xattr, not the expected 16 bytes. Fix the comparison to compare only the first 16 bytes. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> 
All files on the filesystem, currently, are hashed using the same hash
algorithm.  In preparation for files from different packages being
signed using different hash algorithms, this patch adds support for
reading the signature hash algorithm from the 'security.ima' extended
attribute and calculates the appropriate file data hash based on it.

Changelog:
- fix scripts Lindent and checkpatch msgs - Mimi
- fix md5 support for older version, which occupied 20 bytes in the
  xattr, not the expected 16 bytes.  Fix the comparison to compare
  only the first 16 bytes.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
ima: provide support for arbitrary hash algorithms 2013-10-25T21:16:58+00:00 Dmitry Kasatkin d.kasatkin@samsung.com 2013-04-25T07:43:56+00:00 c7c8bb237fdbff932b5e431aebee5ce862ea07d1 In preparation of supporting more hash algorithms with larger hash sizes needed for signature verification, this patch replaces the 20 byte sized digest, with a more flexible structure. The new structure includes the hash algorithm, digest size, and digest. Changelog: - recalculate filedata hash for the measurement list, if the signature hash digest size is greater than 20 bytes. - use generic HASH_ALGO_ - make ima_calc_file_hash static - scripts lindent and checkpatch fixes Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> 
In preparation of supporting more hash algorithms with larger hash sizes
needed for signature verification, this patch replaces the 20 byte sized
digest, with a more flexible structure.  The new structure includes the
hash algorithm, digest size, and digest.

Changelog:
- recalculate filedata hash for the measurement list, if the signature
  hash digest size is greater than 20 bytes.
- use generic HASH_ALGO_
- make ima_calc_file_hash static
- scripts lindent and checkpatch fixes

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>