LSM: general protection fault in legacy_parse_param

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: LSM: general protection fault in legacy_parse_param The usual LSM hook "bail on fail" scheme doesn't work for cases where a security module may return an error code indicating that it does not recognize an input. In this particular case Smack sees a mount option that it recognizes, and returns 0. A call to a BPF hook follows, which returns -ENOPARAM, which confuses the caller because Smack has processed its data. The SELinux hook incorrectly returns 1 on success. There was a time when this was correct, however the current expectation is that it return 0 on success. This is repaired.

References

• https://git.kernel.org/stable/c/ddcdda888e14ca451b3ee83d11b65b2a9c8e783b
• https://git.kernel.org/stable/c/2784604c8c6fc523248f8f80a421c313a9d790b7
• https://git.kernel.org/stable/c/f3f93a1aaafc3032e0a9655fb43deccfb3e953a3
• https://git.kernel.org/stable/c/00fc07fa0b4a004711b6e1a944f0d2e46f7093b7
• https://git.kernel.org/stable/c/cadae7c5e477aaafcba819b8e4a3d1c1a1503b62
• https://git.kernel.org/stable/c/ecff30575b5ad0eda149aadad247b7f75411fd47