CVE-2022-50130: staging: fbtft: core: set smem_len before fb_deferred_io_init call
In the Linux kernel, the following vulnerability has been resolved:
staging: fbtft: core: set smemlen before fbdeferredioinit call
The fbtftframebufferalloc() calls fbdeferredioinit() before initializing info->fix.smemlen. It is set to zero by the framebufferalloc() function. It will trigger a WARNON() at the start of fbdeferredioinit() and the function will not do anything.
Affected Software
Remediation
Event History
Frequently Asked Questions
What configurations are affected?
The issue is in the Linux kernel staging fbtft framebuffer code, specifically the fbtft_framebuffer_alloc() path that initializes deferred I/O before setting info->fix.smem_len.
What happens on an affected system?
Because smem_len is still zero, fb_deferred_io_init() triggers its initial WARN_ON() check and does not perform deferred I/O initialization.
Is a fix available?
Yes. A patch is available that sets smem_len before calling fb_deferred_io_init().