linux-stable.git/drivers/base/firmware_loader, branch v5.2.4

firmware: improve LSM/IMA security behaviour

2019-07-21T07:00:38+00:00

commit 2472d64af2d3561954e2f05365a67692bb852f2a upstream.

The firmware loader queries if LSM/IMA permits it to load firmware
via the sysfs fallback. Unfortunately, the code does the opposite:
it expressly permits sysfs fw loading if security_kernel_load_data(
LOADING_FIRMWARE) returns -EACCES. This happens because a
zero-on-success return value is cast to a bool that's true on success.

Fix the return value handling so we get the correct behaviour.

Fixes: 6e852651f28e ("firmware: add call to LSM hook before firmware sysfs fallback")
Cc: Stable 
Cc: Mimi Zohar 
Cc: Kees Cook 
To: Luis Chamberlain 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sven Van Asbroeck 
Reviewed-by: Mimi Zohar 
Signed-off-by: Greg Kroah-Hartman

firmware_loader: Fix a typo ("syfs" -> "sysfs")

2019-05-01T16:31:11+00:00

"sysfs" was misspelled in a comment and a log message.

Signed-off-by: Jonathan Neuschäfer 
Reviewed-by: Mukesh Ojha 
Signed-off-by: Greg Kroah-Hartman

drivers: base: firmware_loader: add proper SPDX identifiers on files that did not have them.

2019-04-04T18:03:40+00:00

There were two files in the firmware_loader code that did not have SPDX
identifiers on them, so fix that up.

Cc: Luis Chamberlain 
Signed-off-by: Greg Kroah-Hartman

firmware: hardcode the debug message for -ENOENT

2019-02-26T10:59:43+00:00

When no file /path was found, the error code of -ENOENT
enumerated in errno-base.h, is returned. Stating clearly that
the file was not found is much more useful for debugging, So
let's be explicit about that.

Signed-off-by: John Zhao 
Acked-by: Luis Chamberlain 
Signed-off-by: Greg Kroah-Hartman

firmware_loader: move firmware/ to drivers/base/firmware_loader/builtin/

2019-01-22T09:23:18+00:00

Currently, the 'firmware' directory only contains a single Makefile
to embed extra firmware into the kernel.

Move it to the more relevant place.

Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

firmware_loader: move CONFIG_FW_LOADER_USER_HELPER switch to Makefile

2019-01-22T09:23:18+00:00

The whole code of fallback_table.c is surrounded by #ifdef of
CONFIG_FW_LOADER_USER_HELPER.

Move the CONFIG_FW_LOADER_USER_HELPER switch to Makefile so that
it is not compiled at all when this CONFIG option is disabled.

I also removed the confusing comment, "Module or buit-in [sic]".
CONFIG_FW_LOADER_USER_HELPER is a boolean option.
(If it were a module, CONFIG_FW_LOADER_USER_HELPER_MODULE would
be defined instead.)

Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

firmware: Always initialize the fw_priv list object

2018-09-30T15:49:55+00:00

When freeing the fw_priv the item is taken off the list. This causes an
oops in the FW_OPT_NOCACHE case as the list object is not initialized.

Make sure to initialize the list object regardless of this flag.

Fixes: 422b3db2a503 ("firmware: Fix security issue with request_firmware_into_buf()")
Cc: stable@vger.kernel.org
Cc: Rishabh Bhatnagar 
Signed-off-by: Bjorn Andersson 
Reviewed-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

firmware: Fix security issue with request_firmware_into_buf()

2018-09-12T07:31:00+00:00

When calling request_firmware_into_buf() with the FW_OPT_NOCACHE flag
it is expected that firmware is loaded into buffer from memory.
But inside alloc_lookup_fw_priv every new firmware that is loaded is
added to the firmware cache (fwc) list head. So if any driver requests
a firmware that is already loaded the code iterates over the above
mentioned list and it can end up giving a pointer to other device driver's
firmware buffer.
Also the existing copy may either be modified by drivers, remote processors
or even freed. This causes a potential security issue with batched requests
when using request_firmware_into_buf.

Fix alloc_lookup_fw_priv to not add to the fwc head list if FW_OPT_NOCACHE
is set, and also don't do the lookup in the list.

Fixes: 0e742e9275 ("firmware: provide infrastructure to make fw caching optional")
[mcgrof: broken since feature introduction on v4.8]

Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Vikram Mulukutla 
Signed-off-by: Rishabh Bhatnagar 
Signed-off-by: Luis Chamberlain 
Signed-off-by: Greg Kroah-Hartman

mm: provide a fallback for PAGE_KERNEL_RO for architectures

2018-08-17T23:20:29+00:00

Some architectures do not define certain PAGE_KERNEL_* flags, this is
either because:

 a) The way to implement some of these flags is *not yet ported*, or
 b) The architecture *has no way* to describe them

Over time we have accumulated a few PAGE_KERNEL_* fallback workarounds
for architectures in the kernel which do not define them using
*relatively safe* equivalents.  Move these scattered fallback hacks into
asm-generic.

We start off with PAGE_KERNEL_RO using PAGE_KERNEL as a fallback.  This
has been in place on the firmware loader for years.  Move the fallback
into the respective asm-generic header.

Link: http://lkml.kernel.org/r/20180510185507.2439-2-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez 
Reviewed-by: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Cc: Matthew Wilcox 
Cc: Geert Uytterhoeven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

firmware: add call to LSM hook before firmware sysfs fallback

2018-07-16T19:31:57+00:00

Add an LSM hook prior to allowing firmware sysfs fallback loading.

Signed-off-by: Mimi Zohar 
Acked-by: Luis R. Rodriguez 
Reviewed-by: Kees Cook 
Signed-off-by: James Morris