CVE-2022-50558

In the Linux kernel, the following vulnerability has been resolved:

regmap-irq: Use the new numconfigregs property in regmapaddirqchipfwnode

Commit faa87ce9196d ("regmap-irq: Introduce config registers for irq types") added the numconfigregs, then commit 9edd4f5aee84 ("regmap-irq: Deprecate type registers and virtual registers") suggested to replace numtypereg with it. However, regmapaddirqchipfwnode wasn't modified to use the new property. Later on, commit 255a03bb1bb3 ("ASoC: wcd9335: Convert irq chip to config regs") removed the old numtypereg property from the WCD9335 driver's struct regmapirqchip, causing a null pointer dereference in regmapirqsettype when it tried to index d->typebuf as it was never allocated in regmapaddirqchipfwnode:

[ 39.199374] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000

[ 39.200006] Call trace: [ 39.200014] regmapirqsettype+0x84/0x1c0 [ 39.200026] _irqsettrigger+0x60/0x1c0 [ 39.200040] _setupirq+0x2f4/0x78c [ 39.200051] requestthreadedirq+0xe8/0x1a0

Use numconfigregs in regmapaddirqchipfwnode instead of numtypereg, and fall back to it if numconfigregs isn't defined to maintain backward compatibility.