ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size() The step variable is initialized to zero. It is changed in the loop, but if it's not changed it will remain zero. Add a variable check before the division. The observed behavior was introduced by commit 826b5de90c0b ("ALSA: firewire-lib: fix insufficient PCM rule for period/buffer size"), and it is difficult to show that any of the interval parameters will satisfy the snd_interval_test() condition with data from the amdtp_rate_table[] table. Found by Linux Verification Center (linuxtesting.org) with SVACE.

References

• https://git.kernel.org/stable/c/d575414361630b8b0523912532fcd7c79e43468c
• https://git.kernel.org/stable/c/5e431f85c87bbffd93a9830d5a576586f9855291
• https://git.kernel.org/stable/c/7d4eb9e22131ec154e638cbd56629195c9bcbe9a
• https://git.kernel.org/stable/c/d2826873db70a6719cdd9212a6739f3e6234cfc4
• https://git.kernel.org/stable/c/4bdc21506f12b2d432b1f2667e5ff4c75eee58e3
• https://git.kernel.org/stable/c/3452d39c4704aa12504e4190298c721fb01083c3
• https://git.kernel.org/stable/c/72cafe63b35d06b5cfbaf807e90ae657907858da