From 53f5d1688e33f4c9c1e68ba132d50f8aca06fc3b Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Fri, 15 Oct 2021 16:57:39 +0200 Subject: [PATCH] firmware: zynqmp: fix write to an uninitialised pointer in ipi_req() When a caller is not interested in the returned message, the ret_payload pointer is set to NULL in the u-boot-sources. In this case, under EL3, the memory from address 0x0 would be overwritten by ipi_req() with the returned IPI message, damaging the original data under this address. The patch, in case ret_payload is NULL, assigns the pointer to the array holding the IPI message being sent. Signed-off-by: Adrian Fiergolski Signed-off-by: Michal Simek Reviewed-by: Adrian Fiergolski Link: https://lore.kernel.org/r/3178ff7651948270b714daa4adad48b94eaca9ba.1634309856.git.michal.simek@xilinx.com --- drivers/firmware/firmware-zynqmp.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/firmware/firmware-zynqmp.c b/drivers/firmware/firmware-zynqmp.c index 7e0acc5..b44fede 100644 --- a/drivers/firmware/firmware-zynqmp.c +++ b/drivers/firmware/firmware-zynqmp.c @@ -29,6 +29,10 @@ static int ipi_req(const u32 *req, size_t req_len, u32 *res, size_t res_maxlen) { struct zynqmp_ipi_msg msg; int ret; + u32 buffer[PAYLOAD_ARG_CNT]; + + if (!res) + res = buffer; if (req_len > PMUFW_PAYLOAD_ARG_CNT || res_maxlen > PMUFW_PAYLOAD_ARG_CNT) -- 2.7.4