CVE-2021-47216: 
Linux Kernel vulnerability analysis and mitigation

CVE-2021-47216 addresses a kernel pointer leak vulnerability in the Linux kernel's SCSI advansys driver. The vulnerability was discovered in the way pointers were being printed in debug output, where pointers were cast to 'unsigned long' and printed with %lx format specifier instead of using the secure %p or %px format (Kernel Commit).

The vulnerability exists in the advansys.c driver file where the iopbase pointer was being printed using an unsafe format string. The issue occurs in the ascprtadvboard_info function where the pointer was cast to 'unsigned long' and printed using %lx format specifier, potentially leaking kernel pointer information. The fix involves changing the format string from '0x%lx' to '0x%p' to ensure proper pointer hashing when printing debug information (Kernel Commit).

The vulnerability could lead to information disclosure by leaking kernel pointer addresses, which could potentially be used by attackers to bypass kernel address space layout randomization (KASLR) or gather information about the kernel memory layout (NVD).

The vulnerability has been fixed in multiple Linux kernel versions through backported patches. The fix involves updating the pointer printing format in the advansys driver code. Various Linux distributions have released updates containing the fix, including SUSE Linux Enterprise Server and other variants (CERT-FR).