[PATCH 4.19 087/346] coresight: tmc-etr: Check if page is valid before dma_map_page()

Greg Kroah-Hartman
2020-12-28T13:25:23Z

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.org
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
@@ -183,6 +183,8 @@ 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(dev, page, 0, PAGE_SIZE, dir);
if (dma_mapping_error(dev, paddr))