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author | Gustavo A. R. Silva <gustavoars@kernel.org> | 2021-04-19 18:43:32 -0500 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-28 09:12:36 +0200 |
commit | 4487b968e5eacd02c493303dc2b61150bb7fe4b2 (patch) | |
tree | be80253726b15a41df60b8064e2e952446cc8bc9 /drivers/net/ethernet | |
parent | afa091792525dfa6c3c854069ec6b8a5ccc62c11 (diff) |
media: ngene: Fix out-of-bounds bug in ngene_command_config_free_buf()
commit 8d4abca95ecc82fc8c41912fa0085281f19cc29f upstream.
Fix an 11-year old bug in ngene_command_config_free_buf() while
addressing the following warnings caught with -Warray-bounds:
arch/alpha/include/asm/string.h:22:16: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds]
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds]
The problem is that the original code is trying to copy 6 bytes of
data into a one-byte size member _config_ of the wrong structue
FW_CONFIGURE_BUFFERS, in a single call to memcpy(). This causes a
legitimate compiler warning because memcpy() overruns the length
of &com.cmd.ConfigureBuffers.config. It seems that the right
structure is FW_CONFIGURE_FREE_BUFFERS, instead, because it contains
6 more members apart from the header _hdr_. Also, the name of
the function ngene_command_config_free_buf() suggests that the actual
intention is to ConfigureFreeBuffers, instead of ConfigureBuffers
(which takes place in the function ngene_command_config_buf(), above).
Fix this by enclosing those 6 members of struct FW_CONFIGURE_FREE_BUFFERS
into new struct config, and use &com.cmd.ConfigureFreeBuffers.config as
the destination address, instead of &com.cmd.ConfigureBuffers.config,
when calling memcpy().
This also helps with the ongoing efforts to globally enable
-Warray-bounds and get us closer to being able to tighten the
FORTIFY_SOURCE routines on memcpy().
Link: https://github.com/KSPP/linux/issues/109
Fixes: dae52d009fc9 ("V4L/DVB: ngene: Initial check-in")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/linux-hardening/20210420001631.GA45456@embeddedor/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/ethernet')
0 files changed, 0 insertions, 0 deletions