From 26c6d7dc8c6a9fde9d362ab2eef6390efeff145e Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Thu, 21 Mar 2024 09:46:13 +0100 Subject: [PATCH] remoteproc: mediatek: Make sure IPI buffer fits in L2TCM commit 331f91d86f71d0bb89a44217cc0b2a22810bbd42 upstream. The IPI buffer location is read from the firmware that we load to the System Companion Processor, and it's not granted that both the SRAM (L2TCM) size that is defined in the devicetree node is large enough for that, and while this is especially true for multi-core SCP, it's still useful to check on single-core variants as well. Failing to perform this check may make this driver perform R/W operations out of the L2TCM boundary, resulting (at best) in a kernel panic. To fix that, check that the IPI buffer fits, otherwise return a failure and refuse to boot the relevant SCP core (or the SCP at all, if this is single core). Fixes: 3efa0ea743b7 ("remoteproc/mediatek: read IPI buffer offset from FW") Signed-off-by: AngeloGioacchino Del Regno Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240321084614.45253-2-angelogioacchino.delregno@collabora.com Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- drivers/remoteproc/mtk_scp.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c index dcc94ee2458d..c4c535b01181 100644 --- a/drivers/remoteproc/mtk_scp.c +++ b/drivers/remoteproc/mtk_scp.c @@ -126,7 +126,7 @@ static int scp_elf_read_ipi_buf_addr(struct mtk_scp *scp, static int scp_ipi_init(struct mtk_scp *scp, const struct firmware *fw) { int ret; - size_t offset; + size_t buf_sz, offset; /* read the ipi buf addr from FW itself first */ ret = scp_elf_read_ipi_buf_addr(scp, fw, &offset); @@ -138,6 +138,14 @@ static int scp_ipi_init(struct mtk_scp *scp, const struct firmware *fw) } dev_info(scp->dev, "IPI buf addr %#010zx\n", offset); + /* Make sure IPI buffer fits in the L2TCM range assigned to this core */ + buf_sz = sizeof(*scp->recv_buf) + sizeof(*scp->send_buf); + + if (scp->sram_size < buf_sz + offset) { + dev_err(scp->dev, "IPI buffer does not fit in SRAM.\n"); + return -EOVERFLOW; + } + scp->recv_buf = (struct mtk_share_obj __iomem *) (scp->sram_base + offset); scp->send_buf = (struct mtk_share_obj __iomem *)