From: Mao Jinlong jinlmao@codeaurora.org
commit 1cc573d5754e92372a7e30e35468644f8811e1a4 upstream.
alloc_pages_node() return should be checked before calling dma_map_page() to make sure that valid page is mapped or else it can lead to aborts as below:
Unable to handle kernel paging request at virtual address ffffffc008000000 Mem abort info: <snip>... pc : __dma_inv_area+0x40/0x58 lr : dma_direct_map_page+0xd8/0x1c8
Call trace: __dma_inv_area tmc_pages_alloc tmc_alloc_data_pages tmc_alloc_sg_table tmc_init_etr_sg_table tmc_alloc_etr_buf tmc_enable_etr_sink_sysfs tmc_enable_etr_sink coresight_enable_path coresight_enable enable_source_store dev_attr_store sysfs_kf_write
Fixes: 99443ea19e8b ("coresight: Add generic TMC sg table framework") Cc: stable@vger.kernel.org Reviewed-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Mao Jinlong jinlmao@codeaurora.org Signed-off-by: Sai Prakash Ranjan saiprakash.ranjan@codeaurora.org Signed-off-by: Mathieu Poirier mathieu.poirier@linaro.org Link: https://lore.kernel.org/r/20201127175256.1092685-13-mathieu.poirier@linaro.o... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -217,6 +217,8 @@ static int tmc_pages_alloc(struct tmc_pa } else { page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0); + if (!page) + goto err; } paddr = dma_map_page(real_dev, page, 0, PAGE_SIZE, dir); if (dma_mapping_error(real_dev, paddr))