Description
In the Linux kernel, the following vulnerability has been resolved:
iio: accel: bmc150: clamp the device-reported FIFO frame count
__bmc150_accel_fifo_flush() copies the number of samples the device
reports in its hardware FIFO into an on-stack buffer
u16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3];
which is sized for at most BMC150_ACCEL_FIFO_LENGTH (32) samples. The
frame count is read from the FIFO_STATUS register and only masked to its
7 valid bits:
count = val & 0x7F;
so it can be 0..127. The only other limit applied to it is the optional
caller-supplied sample budget:
if (samples && count > samples)
count = samples;
which does not constrain count on the flush-all path (samples == 0), and
leaves it well above 32 whenever samples is larger. count samples are
then transferred into buffer[]:
bmc150_accel_fifo_transfer(data, (u8 *)buffer, count);
bmc150_accel_fifo_transfer() reads count * 6 bytes through regmap, so a
malfunctioning, malicious or counterfeit accelerometer (or an attacker
tampering with the I2C/SPI bus) that reports up to 127 frames writes up
to 762 bytes into the 192-byte buffer: a stack out-of-bounds write of up
to 570 bytes that clobbers the stack canary, saved registers and the
return address.
Clamp count to BMC150_ACCEL_FIFO_LENGTH, the number of samples buffer[]
is sized for, before the transfer, mirroring the watermark clamp already
done in bmc150_accel_set_watermark(). A well-formed flush reports at most
BMC150_ACCEL_FIFO_LENGTH frames, so legitimate devices are unaffected.
iio: accel: bmc150: clamp the device-reported FIFO frame count
__bmc150_accel_fifo_flush() copies the number of samples the device
reports in its hardware FIFO into an on-stack buffer
u16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3];
which is sized for at most BMC150_ACCEL_FIFO_LENGTH (32) samples. The
frame count is read from the FIFO_STATUS register and only masked to its
7 valid bits:
count = val & 0x7F;
so it can be 0..127. The only other limit applied to it is the optional
caller-supplied sample budget:
if (samples && count > samples)
count = samples;
which does not constrain count on the flush-all path (samples == 0), and
leaves it well above 32 whenever samples is larger. count samples are
then transferred into buffer[]:
bmc150_accel_fifo_transfer(data, (u8 *)buffer, count);
bmc150_accel_fifo_transfer() reads count * 6 bytes through regmap, so a
malfunctioning, malicious or counterfeit accelerometer (or an attacker
tampering with the I2C/SPI bus) that reports up to 127 frames writes up
to 762 bytes into the 192-byte buffer: a stack out-of-bounds write of up
to 570 bytes that clobbers the stack canary, saved registers and the
return address.
Clamp count to BMC150_ACCEL_FIFO_LENGTH, the number of samples buffer[]
is sized for, before the transfer, mirroring the watermark clamp already
done in bmc150_accel_set_watermark(). A well-formed flush reports at most
BMC150_ACCEL_FIFO_LENGTH frames, so legitimate devices are unaffected.
Published:
2026-07-25
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
No analysis available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
Sat, 25 Jul 2026 09:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: iio: accel: bmc150: clamp the device-reported FIFO frame count __bmc150_accel_fifo_flush() copies the number of samples the device reports in its hardware FIFO into an on-stack buffer u16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3]; which is sized for at most BMC150_ACCEL_FIFO_LENGTH (32) samples. The frame count is read from the FIFO_STATUS register and only masked to its 7 valid bits: count = val & 0x7F; so it can be 0..127. The only other limit applied to it is the optional caller-supplied sample budget: if (samples && count > samples) count = samples; which does not constrain count on the flush-all path (samples == 0), and leaves it well above 32 whenever samples is larger. count samples are then transferred into buffer[]: bmc150_accel_fifo_transfer(data, (u8 *)buffer, count); bmc150_accel_fifo_transfer() reads count * 6 bytes through regmap, so a malfunctioning, malicious or counterfeit accelerometer (or an attacker tampering with the I2C/SPI bus) that reports up to 127 frames writes up to 762 bytes into the 192-byte buffer: a stack out-of-bounds write of up to 570 bytes that clobbers the stack canary, saved registers and the return address. Clamp count to BMC150_ACCEL_FIFO_LENGTH, the number of samples buffer[] is sized for, before the transfer, mirroring the watermark clamp already done in bmc150_accel_set_watermark(). A well-formed flush reports at most BMC150_ACCEL_FIFO_LENGTH frames, so legitimate devices are unaffected. | |
| Title | iio: accel: bmc150: clamp the device-reported FIFO frame count | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-07-25T08:51:58.887Z
Reserved: 2026-07-19T15:36:31.793Z
Link: CVE-2026-64504
No data.
No data.
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.