Commit Graph

742 Commits

Author SHA1 Message Date
Gustavo A. R. Silva 4739eeafb9 ima: Replace zero-length array with flexible-array member
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-10-29 17:22:59 -05:00
Linus Torvalds 840e5bb326 integrity-v5.10
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Merge tag 'integrity-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity updates from Mimi Zohar:
 "Continuing IMA policy rule cleanup and validation in particular for
  measuring keys, adding/removing/updating informational and error
  messages (e.g. "ima_appraise" boot command line option), and other bug
  fixes (e.g. minimal data size validation before use, return code and
  NULL pointer checking)"

* tag 'integrity-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: Fix NULL pointer dereference in ima_file_hash
  evm: Check size of security.evm before using it
  ima: Remove semicolon at the end of ima_get_binary_runtime_size()
  ima: Don't ignore errors from crypto_shash_update()
  ima: Use kmemdup rather than kmalloc+memcpy
  integrity: include keyring name for unknown key request
  ima: limit secure boot feedback scope for appraise
  integrity: invalid kernel parameters feedback
  ima: add check for enforced appraise option
  integrity: Use current_uid() in integrity_audit_message()
  ima: Fail rule parsing when asymmetric key measurement isn't supportable
  ima: Pre-parse the list of keyrings in a KEY_CHECK rule
2020-10-15 15:58:18 -07:00
Linus Torvalds 726eb70e0d Char/Misc driver patches for 5.10-rc1
Here is the big set of char, misc, and other assorted driver subsystem
 patches for 5.10-rc1.
 
 There's a lot of different things in here, all over the drivers/
 directory.  Some summaries:
 	- soundwire driver updates
 	- habanalabs driver updates
 	- extcon driver updates
 	- nitro_enclaves new driver
 	- fsl-mc driver and core updates
 	- mhi core and bus updates
 	- nvmem driver updates
 	- eeprom driver updates
 	- binder driver updates and fixes
 	- vbox minor bugfixes
 	- fsi driver updates
 	- w1 driver updates
 	- coresight driver updates
 	- interconnect driver updates
 	- misc driver updates
 	- other minor driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char, misc, and other assorted driver subsystem
  patches for 5.10-rc1.

  There's a lot of different things in here, all over the drivers/
  directory. Some summaries:

   - soundwire driver updates

   - habanalabs driver updates

   - extcon driver updates

   - nitro_enclaves new driver

   - fsl-mc driver and core updates

   - mhi core and bus updates

   - nvmem driver updates

   - eeprom driver updates

   - binder driver updates and fixes

   - vbox minor bugfixes

   - fsi driver updates

   - w1 driver updates

   - coresight driver updates

   - interconnect driver updates

   - misc driver updates

   - other minor driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits)
  binder: fix UAF when releasing todo list
  docs: w1: w1_therm: Fix broken xref, mistakes, clarify text
  misc: Kconfig: fix a HISI_HIKEY_USB dependency
  LSM: Fix type of id parameter in kernel_post_load_data prototype
  misc: Kconfig: add a new dependency for HISI_HIKEY_USB
  firmware_loader: fix a kernel-doc markup
  w1: w1_therm: make w1_poll_completion static
  binder: simplify the return expression of binder_mmap
  test_firmware: Test partial read support
  firmware: Add request_partial_firmware_into_buf()
  firmware: Store opt_flags in fw_priv
  fs/kernel_file_read: Add "offset" arg for partial reads
  IMA: Add support for file reads without contents
  LSM: Add "contents" flag to kernel_read_file hook
  module: Call security_kernel_post_load_data()
  firmware_loader: Use security_post_load_data()
  LSM: Introduce kernel_post_load_data() hook
  fs/kernel_read_file: Add file_size output argument
  fs/kernel_read_file: Switch buffer size arg to size_t
  fs/kernel_read_file: Remove redundant size argument
  ...
2020-10-15 10:01:51 -07:00
Linus Torvalds 39a5101f98 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Allow DRBG testing through user-space af_alg
   - Add tcrypt speed testing support for keyed hashes
   - Add type-safe init/exit hooks for ahash

  Algorithms:
   - Mark arc4 as obsolete and pending for future removal
   - Mark anubis, khazad, sead and tea as obsolete
   - Improve boot-time xor benchmark
   - Add OSCCA SM2 asymmetric cipher algorithm and use it for integrity

  Drivers:
   - Fixes and enhancement for XTS in caam
   - Add support for XIP8001B hwrng in xiphera-trng
   - Add RNG and hash support in sun8i-ce/sun8i-ss
   - Allow imx-rngc to be used by kernel entropy pool
   - Use crypto engine in omap-sham
   - Add support for Ingenic X1830 with ingenic"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (205 commits)
  X.509: Fix modular build of public_key_sm2
  crypto: xor - Remove unused variable count in do_xor_speed
  X.509: fix error return value on the failed path
  crypto: bcm - Verify GCM/CCM key length in setkey
  crypto: qat - drop input parameter from adf_enable_aer()
  crypto: qat - fix function parameters descriptions
  crypto: atmel-tdes - use semicolons rather than commas to separate statements
  crypto: drivers - use semicolons rather than commas to separate statements
  hwrng: mxc-rnga - use semicolons rather than commas to separate statements
  hwrng: iproc-rng200 - use semicolons rather than commas to separate statements
  hwrng: stm32 - use semicolons rather than commas to separate statements
  crypto: xor - use ktime for template benchmarking
  crypto: xor - defer load time benchmark to a later time
  crypto: hisilicon/zip - fix the uninitalized 'curr_qm_qp_num'
  crypto: hisilicon/zip - fix the return value when device is busy
  crypto: hisilicon/zip - fix zero length input in GZIP decompress
  crypto: hisilicon/zip - fix the uncleared debug registers
  lib/mpi: Fix unused variable warnings
  crypto: x86/poly1305 - Remove assignments with no effect
  hwrng: npcm - modify readl to readb
  ...
2020-10-13 08:50:16 -07:00
Linus Torvalds e6412f9833 EFI changes for v5.10:
- Preliminary RISC-V enablement - the bulk of it will arrive via the RISCV tree.
 
  - Relax decompressed image placement rules for 32-bit ARM
 
  - Add support for passing MOK certificate table contents via a config table
    rather than a EFI variable.
 
  - Add support for 18 bit DIMM row IDs in the CPER records.
 
  - Work around broken Dell firmware that passes the entire Boot#### variable
    contents as the command line
 
  - Add definition of the EFI_MEMORY_CPU_CRYPTO memory attribute so we can
    identify it in the memory map listings.
 
  - Don't abort the boot on arm64 if the EFI RNG protocol is available but
    returns with an error
 
  - Replace slashes with exclamation marks in efivarfs file names
 
  - Split efi-pstore from the deprecated efivars sysfs code, so we can
    disable the latter on !x86.
 
  - Misc fixes, cleanups and updates.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'efi-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull EFI changes from Ingo Molnar:

 - Preliminary RISC-V enablement - the bulk of it will arrive via the
   RISCV tree.

 - Relax decompressed image placement rules for 32-bit ARM

 - Add support for passing MOK certificate table contents via a config
   table rather than a EFI variable.

 - Add support for 18 bit DIMM row IDs in the CPER records.

 - Work around broken Dell firmware that passes the entire Boot####
   variable contents as the command line

 - Add definition of the EFI_MEMORY_CPU_CRYPTO memory attribute so we
   can identify it in the memory map listings.

 - Don't abort the boot on arm64 if the EFI RNG protocol is available
   but returns with an error

 - Replace slashes with exclamation marks in efivarfs file names

 - Split efi-pstore from the deprecated efivars sysfs code, so we can
   disable the latter on !x86.

 - Misc fixes, cleanups and updates.

* tag 'efi-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  efi: mokvar: add missing include of asm/early_ioremap.h
  efi: efivars: limit availability to X86 builds
  efi: remove some false dependencies on CONFIG_EFI_VARS
  efi: gsmi: fix false dependency on CONFIG_EFI_VARS
  efi: efivars: un-export efivars_sysfs_init()
  efi: pstore: move workqueue handling out of efivars
  efi: pstore: disentangle from deprecated efivars module
  efi: mokvar-table: fix some issues in new code
  efi/arm64: libstub: Deal gracefully with EFI_RNG_PROTOCOL failure
  efivarfs: Replace invalid slashes with exclamation marks in dentries.
  efi: Delete deprecated parameter comments
  efi/libstub: Fix missing-prototypes in string.c
  efi: Add definition of EFI_MEMORY_CPU_CRYPTO and ability to report it
  cper,edac,efi: Memory Error Record: bank group/address and chip id
  edac,ghes,cper: Add Row Extension to Memory Error Record
  efi/x86: Add a quirk to support command line arguments on Dell EFI firmware
  efi/libstub: Add efi_warn and *_once logging helpers
  integrity: Load certs from the EFI MOK config table
  integrity: Move import of MokListRT certs to a separate routine
  efi: Support for MOK variable config table
  ...
2020-10-12 13:26:49 -07:00
Kees Cook 0fa8e08464 fs/kernel_file_read: Add "offset" arg for partial reads
To perform partial reads, callers of kernel_read_file*() must have a
non-NULL file_size argument and a preallocated buffer. The new "offset"
argument can then be used to seek to specific locations in the file to
fill the buffer to, at most, "buf_size" per call.

Where possible, the LSM hooks can report whether a full file has been
read or not so that the contents can be reasoned about.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:04 +02:00
Scott Branden 34736daeec IMA: Add support for file reads without contents
When the kernel_read_file LSM hook is called with contents=false, IMA
can appraise the file directly, without requiring a filled buffer. When
such a buffer is available, though, IMA can continue to use it instead
of forcing a double read here.

Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/lkml/20200706232309.12010-10-scott.branden@broadcom.com/
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-13-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:04 +02:00
Kees Cook 2039bda1fa LSM: Add "contents" flag to kernel_read_file hook
As with the kernel_load_data LSM hook, add a "contents" flag to the
kernel_read_file LSM hook that indicates whether the LSM can expect
a matching call to the kernel_post_read_file LSM hook with the full
contents of the file. With the coming addition of partial file read
support for kernel_read_file*() API, the LSM will no longer be able
to always see the entire contents of a file during the read calls.

For cases where the LSM must read examine the complete file contents,
it will need to do so on its own every time the kernel_read_file
hook is called with contents=false (or reject such cases). Adjust all
existing LSMs to retain existing behavior.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-12-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook 4f2d99b06b firmware_loader: Use security_post_load_data()
Now that security_post_load_data() is wired up, use it instead
of the NULL file argument style of security_post_read_file(),
and update the security_kernel_load_data() call to indicate that a
security_kernel_post_load_data() call is expected.

Wire up the IMA check to match earlier logic. Perhaps a generalized
change to ima_post_load_data() might look something like this:

    return process_buffer_measurement(buf, size,
                                      kernel_load_data_id_str(load_id),
                                      read_idmap[load_id] ?: FILE_CHECK,
                                      0, NULL);

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-10-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook b64fcae74b LSM: Introduce kernel_post_load_data() hook
There are a few places in the kernel where LSMs would like to have
visibility into the contents of a kernel buffer that has been loaded or
read. While security_kernel_post_read_file() (which includes the
buffer) exists as a pairing for security_kernel_read_file(), no such
hook exists to pair with security_kernel_load_data().

Earlier proposals for just using security_kernel_post_read_file() with a
NULL file argument were rejected (i.e. "file" should always be valid for
the security_..._file hooks, but it appears at least one case was
left in the kernel during earlier refactoring. (This will be fixed in
a subsequent patch.)

Since not all cases of security_kernel_load_data() can have a single
contiguous buffer made available to the LSM hook (e.g. kexec image
segments are separately loaded), there needs to be a way for the LSM to
reason about its expectations of the hook coverage. In order to handle
this, add a "contents" argument to the "kernel_load_data" hook that
indicates if the newly added "kernel_post_load_data" hook will be called
with the full contents once loaded. That way, LSMs requiring full contents
can choose to unilaterally reject "kernel_load_data" with contents=false
(which is effectively the existing hook coverage), but when contents=true
they can allow it and later evaluate the "kernel_post_load_data" hook
once the buffer is loaded.

With this change, LSMs can gain coverage over non-file-backed data loads
(e.g. init_module(2) and firmware userspace helper), which will happen
in subsequent patches.

Additionally prepare IMA to start processing these cases.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-9-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook 885352881f fs/kernel_read_file: Add file_size output argument
In preparation for adding partial read support, add an optional output
argument to kernel_read_file*() that reports the file size so callers
can reason more easily about their reading progress.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook 113eeb5177 fs/kernel_read_file: Switch buffer size arg to size_t
In preparation for further refactoring of kernel_read_file*(), rename
the "max_size" argument to the more accurate "buf_size", and correct
its type to size_t. Add kerndoc to explain the specifics of how the
arguments will be used. Note that with buf_size now size_t, it can no
longer be negative (and was never called with a negative value). Adjust
callers to use it as a "maximum size" when *buf is NULL.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-7-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:19 +02:00
Kees Cook f7a4f689bc fs/kernel_read_file: Remove redundant size argument
In preparation for refactoring kernel_read_file*(), remove the redundant
"size" argument which is not needed: it can be included in the return
code, with callers adjusted. (VFS reads already cannot be larger than
INT_MAX.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Scott Branden b89999d004 fs/kernel_read_file: Split into separate include file
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h
include file. That header gets pulled in just about everywhere
and doesn't really need functions not related to the general fs interface.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com
Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Kees Cook c307459b9d fs/kernel_read_file: Remove FIRMWARE_PREALLOC_BUFFER enum
FIRMWARE_PREALLOC_BUFFER is a "how", not a "what", and confuses the LSMs
that are interested in filtering between types of things. The "how"
should be an internal detail made uninteresting to the LSMs.

Fixes: a098ecd2fa ("firmware: support loading into a pre-allocated buffer")
Fixes: fd90bc559b ("ima: based on policy verify firmware signatures (pre-allocated buffer)")
Fixes: 4f0496d8ff ("ima: based on policy warn about loading firmware (pre-allocated buffer)")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201002173828.2099543-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Tianjia Zhang 0b7e44d39c integrity: Asymmetric digsig supports SM2-with-SM3 algorithm
Asymmetric digsig supports SM2-with-SM3 algorithm combination,
so that IMA can also verify SM2's signature data.

Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Tested-by: Xufeng Zhang <yunbo.xufeng@linux.alibaba.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-09-25 17:48:55 +10:00
KP Singh aa662fc04f ima: Fix NULL pointer dereference in ima_file_hash
ima_file_hash can be called when there is no iint->ima_hash available
even though the inode exists in the integrity cache. It is fairly
common for a file to not have a hash. (e.g. an mknodat, prior to the
file being closed).

Another example where this can happen (suggested by Jann Horn):

Process A does:

	while(1) {
		unlink("/tmp/imafoo");
		fd = open("/tmp/imafoo", O_RDWR|O_CREAT|O_TRUNC, 0700);
		if (fd == -1) {
			perror("open");
			continue;
		}
		write(fd, "A", 1);
		close(fd);
	}

and Process B does:

	while (1) {
		int fd = open("/tmp/imafoo", O_RDONLY);
		if (fd == -1)
			continue;
    		char *mapping = mmap(NULL, 0x1000, PROT_READ|PROT_EXEC,
			 	     MAP_PRIVATE, fd, 0);
		if (mapping != MAP_FAILED)
			munmap(mapping, 0x1000);
		close(fd);
  	}

Due to the race to get the iint->mutex between ima_file_hash and
process_measurement iint->ima_hash could still be NULL.

Fixes: 6beea7afcc ("ima: add the ability to query the cached hash of a given file")
Signed-off-by: KP Singh <kpsingh@google.com>
Reviewed-by: Florent Revest <revest@chromium.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-16 17:43:02 -04:00
Lenny Szubowicz 726bd8965a integrity: Load certs from the EFI MOK config table
Because of system-specific EFI firmware limitations, EFI volatile
variables may not be capable of holding the required contents of
the Machine Owner Key (MOK) certificate store when the certificate
list grows above some size. Therefore, an EFI boot loader may pass
the MOK certs via a EFI configuration table created specifically for
this purpose to avoid this firmware limitation.

An EFI configuration table is a much more primitive mechanism
compared to EFI variables and is well suited for one-way passage
of static information from a pre-OS environment to the kernel.

This patch adds the support to load certs from the MokListRT
entry in the MOK variable configuration table, if it's present.
The pre-existing support to load certs from the MokListRT EFI
variable remains and is used if the EFI MOK configuration table
isn't present or can't be successfully used.

Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Link: https://lore.kernel.org/r/20200905013107.10457-4-lszubowi@redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-16 18:53:42 +03:00
Lenny Szubowicz 38a1f03aa2 integrity: Move import of MokListRT certs to a separate routine
Move the loading of certs from the UEFI MokListRT into a separate
routine to facilitate additional MokList functionality.

There is no visible functional change as a result of this patch.
Although the UEFI dbx certs are now loaded before the MokList certs,
they are loaded onto different key rings. So the order of the keys
on their respective key rings is the same.

Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20200905013107.10457-3-lszubowi@redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-16 18:53:42 +03:00
Roberto Sassu 455b6c9112 evm: Check size of security.evm before using it
This patch checks the size for the EVM_IMA_XATTR_DIGSIG and
EVM_XATTR_PORTABLE_DIGSIG types to ensure that the algorithm is read from
the buffer returned by vfs_getxattr_alloc().

Cc: stable@vger.kernel.org # 4.19.x
Fixes: 5feeb61183 ("evm: Allow non-SHA1 digital signatures")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-15 13:47:42 -04:00
Roberto Sassu 4be92db3b5 ima: Remove semicolon at the end of ima_get_binary_runtime_size()
This patch removes the unnecessary semicolon at the end of
ima_get_binary_runtime_size().

Cc: stable@vger.kernel.org
Fixes: d158847ae8 ("ima: maintain memory size needed for serializing the measurement list")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-15 13:47:41 -04:00
Roberto Sassu 60386b8540 ima: Don't ignore errors from crypto_shash_update()
Errors returned by crypto_shash_update() are not checked in
ima_calc_boot_aggregate_tfm() and thus can be overwritten at the next
iteration of the loop. This patch adds a check after calling
crypto_shash_update() and returns immediately if the result is not zero.

Cc: stable@vger.kernel.org
Fixes: 3323eec921 ("integrity: IMA as an integrity service provider")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-15 13:47:37 -04:00
Alex Dewar f60c826d03 ima: Use kmemdup rather than kmalloc+memcpy
Issue identified with Coccinelle.

Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-15 09:57:48 -04:00
Bruno Meneguele 8c2f516c99 integrity: include keyring name for unknown key request
Depending on the IMA policy rule a key may be searched for in multiple
keyrings (e.g. .ima and .platform) and possibly not found.  This patch
improves feedback by including the keyring "description" (name) in the
error message.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
[zohar@linux.ibm.com: updated commit message]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-09 20:05:28 -04:00
Bruno Meneguele e4d7e2df3a ima: limit secure boot feedback scope for appraise
Only emit an unknown/invalid message when setting the IMA appraise mode
to anything other than "enforce", when secureboot is enabled.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
[zohar@linux.ibm.com: updated commit message]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-09 20:01:55 -04:00
Bruno Meneguele 7fe2bb7e7e integrity: invalid kernel parameters feedback
Don't silently ignore unknown or invalid ima_{policy,appraise,hash} and evm
kernel boot command line options.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-08 22:03:50 -04:00
Bruno Meneguele 4afb28ab03 ima: add check for enforced appraise option
The "enforce" string is allowed as an option for ima_appraise= kernel
paramenter per kernel-paramenters.txt and should be considered on the
parameter setup checking as a matter of completeness. Also it allows futher
checking on the options being passed by the user.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-09-08 22:02:57 -04:00
Denis Efremov e44f128768 integrity: Use current_uid() in integrity_audit_message()
Modify integrity_audit_message() to use current_uid().

Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-08-31 17:46:50 -04:00
Tyler Hicks 48ce1ddce1 ima: Fail rule parsing when asymmetric key measurement isn't supportable
Measuring keys is currently only supported for asymmetric keys. In the
future, this might change.

For now, the "func=KEY_CHECK" and "keyrings=" options are only
appropriate when CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Make
this clear at policy load so that IMA policy authors don't assume that
these policy language constructs are supported.

Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Fixes: 5808611ccc ("IMA: Add KEY_CHECK func to measure keys")
Suggested-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-08-31 17:45:14 -04:00
Tyler Hicks 176377d97d ima: Pre-parse the list of keyrings in a KEY_CHECK rule
The ima_keyrings buffer was used as a work buffer for strsep()-based
parsing of the "keyrings=" option of an IMA policy rule. This parsing
was re-performed each time an asymmetric key was added to a kernel
keyring for each loaded policy rule that contained a "keyrings=" option.

An example rule specifying this option is:

 measure func=KEY_CHECK keyrings=a|b|c

The rule says to measure asymmetric keys added to any of the kernel
keyrings named "a", "b", or "c". The size of the buffer size was
equal to the size of the largest "keyrings=" value seen in a previously
loaded rule (5 + 1 for the NUL-terminator in the previous example) and
the buffer was pre-allocated at the time of policy load.

The pre-allocated buffer approach suffered from a couple bugs:

1) There was no locking around the use of the buffer so concurrent key
   add operations, to two different keyrings, would result in the
   strsep() loop of ima_match_keyring() to modify the buffer at the same
   time. This resulted in unexpected results from ima_match_keyring()
   and, therefore, could cause unintended keys to be measured or keys to
   not be measured when IMA policy intended for them to be measured.

2) If the kstrdup() that initialized entry->keyrings in ima_parse_rule()
   failed, the ima_keyrings buffer was freed and set to NULL even when a
   valid KEY_CHECK rule was previously loaded. The next KEY_CHECK event
   would trigger a call to strcpy() with a NULL destination pointer and
   crash the kernel.

Remove the need for a pre-allocated global buffer by parsing the list of
keyrings in a KEY_CHECK rule at the time of policy load. The
ima_rule_entry will contain an array of string pointers which point to
the name of each keyring specified in the rule. No string processing
needs to happen at the time of asymmetric key add so iterating through
the list and doing a string comparison is all that's required at the
time of policy check.

In the process of changing how the "keyrings=" policy option is handled,
a couple additional bugs were fixed:

1) The rule parser accepted rules containing invalid "keyrings=" values
   such as "a|b||c", "a|b|", or simply "|".

2) The /sys/kernel/security/ima/policy file did not display the entire
   "keyrings=" value if the list of keyrings was longer than what could
   fit in the fixed size tbuf buffer in ima_policy_show().

Fixes: 5c7bac9fb2 ("IMA: pre-allocate buffer to hold keyrings string")
Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-08-31 17:45:02 -04:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds ce13266d97 Minor fixes for v5.9.
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Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull security subsystem updates from James Morris:
 "A couple of minor documentation updates only for this release"

* tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  LSM: drop duplicated words in header file comments
  Replace HTTP links with HTTPS ones: security
2020-08-11 14:30:36 -07:00
Alexander A. Klimov c9fecf505a Replace HTTP links with HTTPS ones: security
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
          If both the HTTP and HTTPS versions
          return 200 OK and serve the same content:
            Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
2020-08-06 12:00:05 -07:00
Linus Torvalds 4cec929370 integrity-v5.9
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Merge tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity updates from Mimi Zohar:
 "The nicest change is the IMA policy rule checking. The other changes
  include allowing the kexec boot cmdline line measure policy rules to
  be defined in terms of the inode associated with the kexec kernel
  image, making the IMA_APPRAISE_BOOTPARAM, which governs the IMA
  appraise mode (log, fix, enforce), a runtime decision based on the
  secure boot mode of the system, and including errno in the audit log"

* tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  integrity: remove redundant initialization of variable ret
  ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime
  ima: AppArmor satisfies the audit rule requirements
  ima: Rename internal filter rule functions
  ima: Support additional conditionals in the KEXEC_CMDLINE hook function
  ima: Use the common function to detect LSM conditionals in a rule
  ima: Move comprehensive rule validation checks out of the token parser
  ima: Use correct type for the args_p member of ima_rule_entry.lsm elements
  ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
  ima: Fail rule parsing when appraise_flag=blacklist is unsupportable
  ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond
  ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond
  ima: Fail rule parsing when buffer hook functions have an invalid action
  ima: Free the entire rule if it fails to parse
  ima: Free the entire rule when deleting a list of rules
  ima: Have the LSM free its audit rule
  IMA: Add audit log for failure conditions
  integrity: Add errno field in audit message
2020-08-06 11:35:57 -07:00
Colin Ian King 3db0d0c276 integrity: remove redundant initialization of variable ret
The variable ret is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Fixes: eb5798f2e2 ("integrity: convert digsig to akcipher api")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Addresses-Coverity: ("Unused value")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-27 16:52:09 -04:00
Bruno Meneguele 311aa6aafe ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime
The IMA_APPRAISE_BOOTPARAM config allows enabling different "ima_appraise="
modes - log, fix, enforce - at run time, but not when IMA architecture
specific policies are enabled.  This prevents properly labeling the
filesystem on systems where secure boot is supported, but not enabled on the
platform.  Only when secure boot is actually enabled should these IMA
appraise modes be disabled.

This patch removes the compile time dependency and makes it a runtime
decision, based on the secure boot state of that platform.

Test results as follows:

-> x86-64 with secure boot enabled

[    0.015637] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[    0.015668] ima: Secure boot enabled: ignoring ima_appraise=fix boot parameter option

-> powerpc with secure boot disabled

[    0.000000] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[    0.000000] Secure boot mode disabled

-> Running the system without secure boot and with both options set:

CONFIG_IMA_APPRAISE_BOOTPARAM=y
CONFIG_IMA_ARCH_POLICY=y

Audit prompts "missing-hash" but still allow execution and, consequently,
filesystem labeling:

type=INTEGRITY_DATA msg=audit(07/09/2020 12:30:27.778:1691) : pid=4976
uid=root auid=root ses=2
subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 op=appraise_data
cause=missing-hash comm=bash name=/usr/bin/evmctl dev="dm-0" ino=493150
res=no

Cc: stable@vger.kernel.org
Fixes: d958083a8f ("x86/ima: define arch_get_ima_policy() for x86")
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Cc: stable@vger.kernel.org # 5.0
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 18:18:49 -04:00
Tyler Hicks 1768215a65 ima: AppArmor satisfies the audit rule requirements
AppArmor meets all the requirements for IMA in terms of audit rules
since commit e79c26d040 ("apparmor: Add support for audit rule
filtering"). Update IMA's Kconfig section for CONFIG_IMA_LSM_RULES to
reflect this.

Fixes: e79c26d040 ("apparmor: Add support for audit rule filtering")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 18:18:37 -04:00
Tyler Hicks b8867eedcf ima: Rename internal filter rule functions
Rename IMA's internal filter rule functions from security_filter_rule_*()
to ima_filter_rule_*(). This avoids polluting the security_* namespace,
which is typically reserved for general security subsystem
infrastructure.

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Suggested-by: Casey Schaufler <casey@schaufler-ca.com>
[zohar@linux.ibm.com: reword using the term "filter", not "audit"]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 18:18:23 -04:00
Tyler Hicks 4834177e63 ima: Support additional conditionals in the KEXEC_CMDLINE hook function
Take the properties of the kexec kernel's inode and the current task
ownership into consideration when matching a KEXEC_CMDLINE operation to
the rules in the IMA policy. This allows for some uniformity when
writing IMA policy rules for KEXEC_KERNEL_CHECK, KEXEC_INITRAMFS_CHECK,
and KEXEC_CMDLINE operations.

Prior to this patch, it was not possible to write a set of rules like
this:

 dont_measure func=KEXEC_KERNEL_CHECK obj_type=foo_t
 dont_measure func=KEXEC_INITRAMFS_CHECK obj_type=foo_t
 dont_measure func=KEXEC_CMDLINE obj_type=foo_t
 measure func=KEXEC_KERNEL_CHECK
 measure func=KEXEC_INITRAMFS_CHECK
 measure func=KEXEC_CMDLINE

The inode information associated with the kernel being loaded by a
kexec_kernel_load(2) syscall can now be included in the decision to
measure or not

Additonally, the uid, euid, and subj_* conditionals can also now be
used in KEXEC_CMDLINE rules. There was no technical reason as to why
those conditionals weren't being considered previously other than
ima_match_rules() didn't have a valid inode to use so it immediately
bailed out for KEXEC_CMDLINE operations rather than going through the
full list of conditional comparisons.

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:28:16 -04:00
Tyler Hicks 592b24cbdc ima: Use the common function to detect LSM conditionals in a rule
Make broader use of ima_rule_contains_lsm_cond() to check if a given
rule contains an LSM conditional. This is a code cleanup and has no
user-facing change.

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:28:16 -04:00
Tyler Hicks 30031b0ec8 ima: Move comprehensive rule validation checks out of the token parser
Use ima_validate_rule(), at the end of the token parsing stage, to
verify combinations of actions, hooks, and flags. This is useful to
increase readability by consolidating such checks into a single function
and also because rule conditionals can be specified in arbitrary order
making it difficult to do comprehensive rule validation until the entire
rule has been parsed.

This allows for the check that ties together the "keyrings" conditional
with the KEY_CHECK function hook to be moved into the final rule
validation.

The modsig check no longer needs to compiled conditionally because the
token parser will ensure that modsig support is enabled before accepting
"imasig|modsig" appraise type values. The final rule validation will
ensure that appraise_type and appraise_flag options are only present in
appraise rules.

Finally, this allows for the check that ties together the "pcr"
conditional with the measure action to be moved into the final rule
validation.

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:28:15 -04:00
Tyler Hicks aa0c0227d3 ima: Use correct type for the args_p member of ima_rule_entry.lsm elements
Make args_p be of the char pointer type rather than have it be a void
pointer that gets casted to char pointer when it is used. It is a simple
NUL-terminated string as returned by match_strdup().

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:28:14 -04:00
Tyler Hicks 39e5993d0d ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
The args_p member is a simple string that is allocated by
ima_rule_init(). Shallow copy it like other non-LSM references in
ima_rule_entry structs.

There are no longer any necessary error path cleanups to do in
ima_lsm_copy_rule().

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:28:13 -04:00
Tyler Hicks 5f3e92657b ima: Fail rule parsing when appraise_flag=blacklist is unsupportable
Verifying that a file hash is not blacklisted is currently only
supported for files with appended signatures (modsig).  In the future,
this might change.

For now, the "appraise_flag" option is only appropriate for appraise
actions and its "blacklist" value is only appropriate when
CONFIG_IMA_APPRAISE_MODSIG is enabled and "appraise_flag=blacklist" is
only appropriate when "appraise_type=imasig|modsig" is also present.
Make this clear at policy load so that IMA policy authors don't assume
that other uses of "appraise_flag=blacklist" are supported.

Fixes: 273df864cf ("ima: Check against blacklisted hashes for files with modsig")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reivewed-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-20 13:06:26 -04:00
Tyler Hicks eb624fe214 ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond
The KEY_CHECK function only supports the uid, pcr, and keyrings
conditionals. Make this clear at policy load so that IMA policy authors
don't assume that other conditionals are supported.

Fixes: 5808611ccc ("IMA: Add KEY_CHECK func to measure keys")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00
Tyler Hicks db2045f589 ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond
The KEXEC_CMDLINE hook function only supports the pcr conditional. Make
this clear at policy load so that IMA policy authors don't assume that
other conditionals are supported.

Since KEXEC_CMDLINE's inception, ima_match_rules() has always returned
true on any loaded KEXEC_CMDLINE rule without any consideration for
other conditionals present in the rule. Make it clear that pcr is the
only supported KEXEC_CMDLINE conditional by returning an error during
policy load.

An example of why this is a problem can be explained with the following
rule:

 dont_measure func=KEXEC_CMDLINE obj_type=foo_t

An IMA policy author would have assumed that rule is valid because the
parser accepted it but the result was that measurements for all
KEXEC_CMDLINE operations would be disabled.

Fixes: b0935123a1 ("IMA: Define a new hook to measure the kexec boot command line arguments")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00
Tyler Hicks 712183437e ima: Fail rule parsing when buffer hook functions have an invalid action
Buffer based hook functions, such as KEXEC_CMDLINE and KEY_CHECK, can
only measure. The process_buffer_measurement() function quietly ignores
all actions except measure so make this behavior clear at the time of
policy load.

The parsing of the keyrings conditional had a check to ensure that it
was only specified with measure actions but the check should be on the
hook function and not the keyrings conditional since
"appraise func=KEY_CHECK" is not a valid rule.

Fixes: b0935123a1 ("IMA: Define a new hook to measure the kexec boot command line arguments")
Fixes: 5808611ccc ("IMA: Add KEY_CHECK func to measure keys")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00
Tyler Hicks 2bdd737c56 ima: Free the entire rule if it fails to parse
Use ima_free_rule() to fix memory leaks of allocated ima_rule_entry
members, such as .fsname and .keyrings, when an error is encountered
during rule parsing.

Set the args_p pointer to NULL after freeing it in the error path of
ima_lsm_rule_init() so that it isn't freed twice.

This fixes a memory leak seen when loading an rule that contains an
additional piece of allocated memory, such as an fsname, followed by an
invalid conditional:

 # echo "measure fsname=tmpfs bad=cond" > /sys/kernel/security/ima/policy
 -bash: echo: write error: Invalid argument
 # echo scan > /sys/kernel/debug/kmemleak
 # cat /sys/kernel/debug/kmemleak
 unreferenced object 0xffff98e7e4ece6c0 (size 8):
   comm "bash", pid 672, jiffies 4294791843 (age 21.855s)
   hex dump (first 8 bytes):
     74 6d 70 66 73 00 6b a5                          tmpfs.k.
   backtrace:
     [<00000000abab7413>] kstrdup+0x2e/0x60
     [<00000000f11ede32>] ima_parse_add_rule+0x7d4/0x1020
     [<00000000f883dd7a>] ima_write_policy+0xab/0x1d0
     [<00000000b17cf753>] vfs_write+0xde/0x1d0
     [<00000000b8ddfdea>] ksys_write+0x68/0xe0
     [<00000000b8e21e87>] do_syscall_64+0x56/0xa0
     [<0000000089ea7b98>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: f1b08bbcbd ("ima: define a new policy condition based on the filesystem name")
Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00
Tyler Hicks 465aee77aa ima: Free the entire rule when deleting a list of rules
Create a function, ima_free_rule(), to free all memory associated with
an ima_rule_entry. Use the new function to fix memory leaks of allocated
ima_rule_entry members, such as .fsname and .keyrings, when deleting a
list of rules.

Make the existing ima_lsm_free_rule() function specific to the LSM
audit rule array of an ima_rule_entry and require that callers make an
additional call to kfree to free the ima_rule_entry itself.

This fixes a memory leak seen when loading by a valid rule that contains
an additional piece of allocated memory, such as an fsname, followed by
an invalid rule that triggers a policy load failure:

 # echo -e "dont_measure fsname=securityfs\nbad syntax" > \
    /sys/kernel/security/ima/policy
 -bash: echo: write error: Invalid argument
 # echo scan > /sys/kernel/debug/kmemleak
 # cat /sys/kernel/debug/kmemleak
 unreferenced object 0xffff9bab67ca12c0 (size 16):
   comm "bash", pid 684, jiffies 4295212803 (age 252.344s)
   hex dump (first 16 bytes):
     73 65 63 75 72 69 74 79 66 73 00 6b 6b 6b 6b a5  securityfs.kkkk.
   backtrace:
     [<00000000adc80b1b>] kstrdup+0x2e/0x60
     [<00000000d504cb0d>] ima_parse_add_rule+0x7d4/0x1020
     [<00000000444825ac>] ima_write_policy+0xab/0x1d0
     [<000000002b7f0d6c>] vfs_write+0xde/0x1d0
     [<0000000096feedcf>] ksys_write+0x68/0xe0
     [<0000000052b544a2>] do_syscall_64+0x56/0xa0
     [<000000007ead1ba7>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: f1b08bbcbd ("ima: define a new policy condition based on the filesystem name")
Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00
Tyler Hicks 9ff8a616df ima: Have the LSM free its audit rule
Ask the LSM to free its audit rule rather than directly calling kfree().
Both AppArmor and SELinux do additional work in their audit_rule_free()
hooks. Fix memory leaks by allowing the LSMs to perform necessary work.

Fixes: b169424551 ("ima: use the lsm policy update notifier")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Janne Karhunen <janne.karhunen@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-16 21:53:55 -04:00