genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask() If ipi_send_{mask|single}() is called with an invalid interrupt number, all the local variables there will be NULL. ipi_send_verify() which is invoked from these functions does verify its 'data' parameter, resulting in a kernel oops in irq_data_get_affinity_mask() as the passed NULL pointer gets dereferenced. Add a missing NULL pointer check in ipi_send_verify()... Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool.

References

• https://git.kernel.org/stable/c/926aef60ea64cd9becf2829f7388f48dbe8bcb11
• https://git.kernel.org/stable/c/7448c73d64075051f50caed2c62f46553b69ab8a
• https://git.kernel.org/stable/c/feabecaff5902f896531dde90646ca5dfa9d4f7d