soc: qcom: dcc: add check if sram data oversteps

If the size of captured data oversteps over SRAM boundary then
it causes corruption of configuration data. Add boundary check
while programming configuration linked list in SRAM, to avoid
this problem.

Change-Id: Idd33f53560585fdbfee4d3822fd93d6f3a365e17
Signed-off-by: Xiaogang Cui <xiaogang@codeaurora.org>
Signed-off-by: Shashank Mittal <mittals@codeaurora.org>
This commit is contained in:
Xiaogang Cui 2015-10-09 16:33:08 +08:00 committed by Jeevan Shriram
parent 59a1235ece
commit 4b36c0b4c4

View file

@ -253,7 +253,7 @@ static int __dcc_ll_cfg(struct dcc_drvdata *drvdata)
uint32_t prev_addr, addr;
uint32_t prev_off = 0, off;
uint32_t link;
uint32_t pos;
uint32_t pos, total_len = 0;
struct dcc_config_entry *entry;
if (list_empty(&drvdata->config_head)) {
@ -272,6 +272,7 @@ static int __dcc_ll_cfg(struct dcc_drvdata *drvdata)
addr = (entry->base >> 4) & BM(0, 27);
addr |= BIT(31);
off = entry->offset/4;
total_len += entry->len * 4;
if (!prev_addr || prev_addr != addr || prev_off > off) {
/* Check if we need to write link of prev entry */
@ -289,7 +290,7 @@ static int __dcc_ll_cfg(struct dcc_drvdata *drvdata)
prev_off = 0;
}
if ((off - prev_off) > 0xFF || entry->len > 0x7F) {
if ((off - prev_off) > 0xFF || entry->len > MAX_DCC_LEN) {
dev_err(drvdata->dev,
"DCC: Progamming error! Base: 0x%x, offset 0x%x.\n",
entry->base, entry->offset);
@ -339,8 +340,25 @@ static int __dcc_ll_cfg(struct dcc_drvdata *drvdata)
dcc_sram_writel(drvdata, 0, sram_offset);
sram_offset += 4;
drvdata->ram_cfg = (sram_offset / 4);
/* check if the data will overstep */
if (drvdata->data_sink == DCC_DATA_SINK_SRAM
&& drvdata->func_type == DCC_FUNC_TYPE_CAPTURE) {
if (sram_offset + total_len > drvdata->ram_size) {
sram_offset += total_len;
goto overstep;
}
} else {
if (sram_offset > drvdata->ram_size)
goto overstep;
}
drvdata->ram_cfg = (sram_offset / 4);
return 0;
overstep:
ret = -EINVAL;
memset_io(drvdata->ram_base, 0, drvdata->ram_size);
dev_err(drvdata->dev, "DCC SRAM oversteps, 0x%x (0x%x)\n",
sram_offset, drvdata->ram_size);
err:
return ret;
}