6.6-stable review patch. If anyone has any objections, please let me know.
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From: Richard Fitzgerald rf@opensource.cirrus.com
[ Upstream commit 3019b86bce16fbb5bc1964f3544d0ce7d0137278 ]
Fix the checking that firmware file buffer is large enough for the wmfw header, to prevent overrunning the buffer.
The original code tested that the firmware data buffer contained enough bytes for the sums of the size of the structs
wmfw_header + wmfw_adsp1_sizes + wmfw_footer
But wmfw_adsp1_sizes is only used on ADSP1 firmware. For ADSP2 and Halo Core the equivalent struct is wmfw_adsp2_sizes, which is 4 bytes longer. So the length check didn't guarantee that there are enough bytes in the firmware buffer for a header with wmfw_adsp2_sizes.
This patch splits the length check into three separate parts. Each of the wmfw_header, wmfw_adsp?_sizes and wmfw_footer are checked separately before they are used.
Signed-off-by: Richard Fitzgerald rf@opensource.cirrus.com Fixes: f6bc909e7673 ("firmware: cs_dsp: add driver to support firmware loading on Cirrus Logic DSPs") Link: https://patch.msgid.link/20240627141432.93056-2-rf@opensource.cirrus.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/cirrus/cs_dsp.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/firmware/cirrus/cs_dsp.c b/drivers/firmware/cirrus/cs_dsp.c index 79d4254d1f9bc..f0c3c4011411d 100644 --- a/drivers/firmware/cirrus/cs_dsp.c +++ b/drivers/firmware/cirrus/cs_dsp.c @@ -1267,6 +1267,10 @@ static unsigned int cs_dsp_adsp1_parse_sizes(struct cs_dsp *dsp, const struct wmfw_adsp1_sizes *adsp1_sizes;
adsp1_sizes = (void *)&firmware->data[pos]; + if (sizeof(*adsp1_sizes) > firmware->size - pos) { + cs_dsp_err(dsp, "%s: file truncated\n", file); + return 0; + }
cs_dsp_dbg(dsp, "%s: %d DM, %d PM, %d ZM\n", file, le32_to_cpu(adsp1_sizes->dm), le32_to_cpu(adsp1_sizes->pm), @@ -1283,6 +1287,10 @@ static unsigned int cs_dsp_adsp2_parse_sizes(struct cs_dsp *dsp, const struct wmfw_adsp2_sizes *adsp2_sizes;
adsp2_sizes = (void *)&firmware->data[pos]; + if (sizeof(*adsp2_sizes) > firmware->size - pos) { + cs_dsp_err(dsp, "%s: file truncated\n", file); + return 0; + }
cs_dsp_dbg(dsp, "%s: %d XM, %d YM %d PM, %d ZM\n", file, le32_to_cpu(adsp2_sizes->xm), le32_to_cpu(adsp2_sizes->ym), @@ -1322,7 +1330,6 @@ static int cs_dsp_load(struct cs_dsp *dsp, const struct firmware *firmware, struct regmap *regmap = dsp->regmap; unsigned int pos = 0; const struct wmfw_header *header; - const struct wmfw_adsp1_sizes *adsp1_sizes; const struct wmfw_footer *footer; const struct wmfw_region *region; const struct cs_dsp_region *mem; @@ -1338,10 +1345,8 @@ static int cs_dsp_load(struct cs_dsp *dsp, const struct firmware *firmware,
ret = -EINVAL;
- pos = sizeof(*header) + sizeof(*adsp1_sizes) + sizeof(*footer); - if (pos >= firmware->size) { - cs_dsp_err(dsp, "%s: file too short, %zu bytes\n", - file, firmware->size); + if (sizeof(*header) >= firmware->size) { + ret = -EOVERFLOW; goto out_fw; }
@@ -1369,13 +1374,16 @@ static int cs_dsp_load(struct cs_dsp *dsp, const struct firmware *firmware,
pos = sizeof(*header); pos = dsp->ops->parse_sizes(dsp, file, pos, firmware); + if ((pos == 0) || (sizeof(*footer) > firmware->size - pos)) { + ret = -EOVERFLOW; + goto out_fw; + }
footer = (void *)&firmware->data[pos]; pos += sizeof(*footer);
if (le32_to_cpu(header->len) != pos) { - cs_dsp_err(dsp, "%s: unexpected header length %d\n", - file, le32_to_cpu(header->len)); + ret = -EOVERFLOW; goto out_fw; }
@@ -1501,6 +1509,9 @@ static int cs_dsp_load(struct cs_dsp *dsp, const struct firmware *firmware, cs_dsp_buf_free(&buf_list); kfree(text);
+ if (ret == -EOVERFLOW) + cs_dsp_err(dsp, "%s: file content overflows file data\n", file); + return ret; }