buffer overflow in arm_conv_q15 and q7

[christophe0606]

Running tests on Zephyr for mps3_an547 (Cortex-M55 with DSP support) west build -p -b mps3_an547 tests/lib/cmsis_dsp/filtering -T libraries.cmsis_dsp.filtering.misc.fpu -t run A buffer overflow is detected.

Code in the tested functions seem suspicious: arm_conv_q15 and arm_conv_q7.

The loop in arm_conv_q31 does not display the same suspicious exit condition.

For what it’s worth, changing those conditions to either >= 2 or > 1 solves the issue and lets the test pass successfully.

[christophe0606]

Tentative fix in the latest commit.

[ithinuel]

This can be confirmed by running the Zephyr tests for cmsis-dsp (eg here) on an547 with:

west build -p -b mps3_an547 tests/lib/cmsis_dsp/filtering -T libraries.cmsis_dsp.filtering.misc.fpu -t run

[christophe0606]

It was confirmed as solved (private communication).