hinic: Replace memcpy() with direct assignment

Under CONFIG_FORTIFY_SOURCE=y and CONFIG_UBSAN_BOUNDS=y, Clang is bugged
here for calculating the size of the destination buffer (0x10 instead of
0x14). This copy is a fixed size (sizeof(struct fw_section_info_st)), with
the source and dest being struct fw_section_info_st, so the memcpy should
be safe, assuming the index is within bounds, which is UBSAN_BOUNDS's
responsibility to figure out.

Avoid the whole thing and just do a direct assignment. This results in
no change to the executable code.

Cc: "David S. Miller" <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Tom Rix <[email protected]>
Cc: Leon Romanovsky <[email protected]>
Cc: Jiri Pirko <[email protected]>
Cc: Vladimir Oltean <[email protected]>
Cc: Simon Horman <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://github.com/ClangBuiltLinux/linux/issues/1592
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Tested-by: Nathan Chancellor <[email protected]> # build
Signed-off-by: David S. Miller <[email protected]>

diff --git a/drivers/net/ethernet/huawei/hinic/hinic_devlink.c b/drivers/net/ethernet/huawei/hinic/hinic_devlink.c
index 60ae8bfc5f69a768e8f3d443e1ec1034296b7c70..1749d26f4befc96afb9800bb81c595defd030bef 100644 (file)
--- a/drivers/net/ethernet/huawei/hinic/hinic_devlink.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_devlink.c
@@ -43,9 +43,7 @@ static bool check_image_valid(struct hinic_devlink_priv *priv, const u8 *buf,
 
        for (i = 0; i < fw_image->fw_info.fw_section_cnt; i++) {
                len += fw_image->fw_section_info[i].fw_section_len;
-               memcpy(&host_image->image_section_info[i],
-                      &fw_image->fw_section_info[i],
-                      sizeof(struct fw_section_info_st));
+               host_image->image_section_info[i] = fw_image->fw_section_info[i];
        }
 
        if (len != fw_image->fw_len ||