linux.git/security/integrity/ima/ima_template_lib.c, branch v5.17

ima: Fix fall-through warning for Clang

2021-06-09T03:33:48+00:00

In preparation to enable -Wimplicit-fallthrough for Clang, fix a
fall-through warning by explicitly adding a break statement instead
of just letting the code fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva 
Reviewed-by: Kees Cook 
Signed-off-by: Mimi Zohar

ima/evm: Fix type mismatch

2021-06-08T20:29:10+00:00

The endianness of a variable written to the measurement list cannot be
determined at compile time, as it depends on the value of the
ima_canonical_fmt global variable (set through a kernel option with the
same name if the machine is big endian).

If ima_canonical_fmt is false, the endianness of a variable is the same as
the machine; if ima_canonical_fmt is true, the endianness is little endian.
The warning arises due to this type of instruction:

var = cpu_to_leXX(var)

which tries to assign a value in little endian to a variable with native
endianness (little or big endian).

Given that the variables set with this instruction are not used in any
operation but just written to a buffer, it is safe to force the type of the
value being set to be the same of the type of the variable with:

var = (__force )cpu_to_leXX(var)

Reported-by: kernel test robot 
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Set correct casting types

2021-06-08T20:29:10+00:00

The code expects that the values being parsed from a buffer when the
ima_canonical_fmt global variable is true are in little endian. Thus, this
patch sets the casting types accordingly.

Reported-by: kernel test robot 
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template fields xattrnames, xattrlengths and xattrvalues

2021-06-02T22:56:13+00:00

This patch defines the new template fields xattrnames, xattrlengths and
xattrvalues, which contain respectively a list of xattr names (strings,
separated by |), lengths (u32, hex) and values (hex). If an xattr is not
present, the name and length are not displayed in the measurement list.

Reported-by: kernel test robot  (Missing prototype def)
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template field imode

2021-06-01T19:17:30+00:00

This patch defines the new template field imode, which includes the
inode mode. It can be used by a remote verifier to verify the EVM portable
signature, if it was included with the template fields sig or evmsig.

Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template fields iuid and igid

2021-06-01T19:17:30+00:00

This patch defines the new template fields iuid and igid, which include
respectively the inode UID and GID. For idmapped mounts, still the original
UID and GID are provided.

These fields can be used to verify the EVM portable signature, if it was
included with the template fields sig or evmsig.

Signed-off-by: Roberto Sassu 
Acked-by: Christian Brauner 
Signed-off-by: Mimi Zohar

ima: Add ima_show_template_uint() template library function

2021-06-01T19:17:30+00:00

This patch introduces the new function ima_show_template_uint(). This can
be used for showing integers of different sizes in ASCII format. The
function ima_show_template_data_ascii() automatically determines how to
print a stored integer by checking the integer size.

If integers have been written in canonical format,
ima_show_template_data_ascii() calls the appropriate leXX_to_cpu() function
to correctly display the value.

Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Introduce template field evmsig and write to field sig as fallback

2021-06-01T16:30:51+00:00

With the patch to accept EVM portable signatures when the
appraise_type=imasig requirement is specified in the policy, appraisal can
be successfully done even if the file does not have an IMA signature.

However, remote attestation would not see that a different signature type
was used, as only IMA signatures can be included in the measurement list.
This patch solves the issue by introducing the new template field 'evmsig'
to show EVM portable signatures and by including its value in the existing
field 'sig' if the IMA signature is not found.

Suggested-by: Mimi Zohar 
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

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

Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2020-08-11T21:30:36+00:00

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