[PATCH 5.7 096/204] remoteproc: qcom_q6v5_mss: Validate modem blob firmware size before load

Greg Kroah-Hartman
2020-08-20T13:02:04Z

From: Sibi Sankar <sibis@codeaurora.org>

commit 135b9e8d1cd8ba5ac9ad9bcf24b464b7b052e5b8 upstream.

The following mem abort is observed when one of the modem blob firmware
size exceeds the allocated mpss region. Fix this by restricting the copy
size to segment size using request_firmware_into_buf before load.

Err Logs:
Unable to handle kernel paging request at virtual address
Mem abort info:
...
Call trace:
__memcpy+0x110/0x180
rproc_start+0xd0/0x190
rproc_boot+0x404/0x550
state_store+0x54/0xf8
dev_attr_store+0x44/0x60
sysfs_kf_write+0x58/0x80
kernfs_fop_write+0x140/0x230
vfs_write+0xc4/0x208
ksys_write+0x74/0xf8
...

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Fixes: 051fb70fd4ea4 ("remoteproc: qcom: Driver for the self-authenticating Hexagon v5")
Cc: stable@vger.kernel.org
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Link: https://lore.kernel.org/r/20200722201047.12975-3-sibis@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/remoteproc/qcom_q6v5_mss.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -1145,15 +1145,14 @@ static int q6v5_mpss_load(struct q6v5 *q
} else if (phdr->p_filesz) {
/* Replace "xxx.xxx" with "xxx.bxx" */
sprintf(fw_name + fw_name_len - 3, "b%02d", i);
- ret = request_firmware(&seg_fw, fw_name, qproc->dev);
+ ret = request_firmware_into_buf(&seg_fw, fw_name, qproc->dev,
+ ptr, phdr->p_filesz);
if (ret) {
dev_err(qproc->dev, "failed to load %s\n", fw_name);
iounmap(ptr);
goto release_firmware;
}

- memcpy(ptr, seg_fw->data, seg_fw->size);
-
release_firmware(seg_fw);
}