In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields.
Instead of writing across a field boundary with memset(), move the call to just the array, and an explicit zeroing of the prior field.
Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Qinglang Miao miaoqinglang@huawei.com Cc: "Gustavo A. R. Silva" gustavoars@kernel.org Cc: Hulk Robot hulkci@huawei.com Cc: Wang Wensheng wangwensheng4@huawei.com Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Kees Cook keescook@chromium.org Reviewed-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/lkml/87czqsnmw9.fsf@mpe.ellerman.id.au --- drivers/macintosh/smu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c index 94fb63a7b357..59ce431da7ef 100644 --- a/drivers/macintosh/smu.c +++ b/drivers/macintosh/smu.c @@ -848,7 +848,8 @@ int smu_queue_i2c(struct smu_i2c_cmd *cmd) cmd->read = cmd->info.devaddr & 0x01; switch(cmd->info.type) { case SMU_I2C_TRANSFER_SIMPLE: - memset(&cmd->info.sublen, 0, 4); + cmd->info.sublen = 0; + memset(&cmd->info.subaddr, 0, 3); break; case SMU_I2C_TRANSFER_COMBINED: cmd->info.devaddr &= 0xfe;