Go to file
Kees Cook 231d8c46b1 spi: dw: Avoid stack content exposure
[ Upstream commit 386f771aad ]

Since "data" is u32, &data is a "u32 *" type, which means pointer math
will move in u32-sized steps. This was meant to be a byte offset, so
cast &data to "char *" to aim the copy into the correct location.

Seen with -Warray-bounds (and found by Coverity):

In file included from ./include/linux/string.h:269,
                 from ./arch/powerpc/include/asm/paca.h:15,
                 from ./arch/powerpc/include/asm/current.h:13,
                 from ./include/linux/mutex.h:14,
                 from ./include/linux/notifier.h:14,
                 from ./include/linux/clk.h:14,
                 from drivers/spi/spi-dw-bt1.c:12:
In function 'memcpy',
    inlined from 'dw_spi_bt1_dirmap_copy_from_map' at drivers/spi/spi-dw-bt1.c:87:3:
./include/linux/fortify-string.h:20:29: warning: '__builtin_memcpy' offset 4 is out of the bounds [0, 4] of object 'data' with type 'u32' {aka 'unsigned int'} [-Warray-bounds]
   20 | #define __underlying_memcpy __builtin_memcpy
      |                             ^
./include/linux/fortify-string.h:191:9: note: in expansion of macro '__underlying_memcpy'
  191 |  return __underlying_memcpy(p, q, size);
      |         ^~~~~~~~~~~~~~~~~~~
drivers/spi/spi-dw-bt1.c: In function 'dw_spi_bt1_dirmap_copy_from_map':
drivers/spi/spi-dw-bt1.c:77:6: note: 'data' declared here
   77 |  u32 data;
      |      ^~~~

Addresses-Coverity: CID 1497771 Out-of-bounds access
Fixes: abf0090753 ("spi: dw: Add Baikal-T1 SPI Controller glue driver")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20210211203714.1929862-1-keescook@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04 11:38:07 +01:00
2021-02-26 10:14:35 +01:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 4.8 GiB
Languages
C 97.7%
Assembly 1.3%
Shell 0.3%
Makefile 0.3%
Python 0.2%
Other 0.1%