In the Linux kernel, the following vulnerability has been resolved: Revert "net/smc: Introduce TCP ULP support" This reverts commit d7cd421da9da2cc7b4d25b8537f66db5c8331c40. As reported by Al Viro, the TCP ULP support for SMC is fundamentally broken. The implementation attempts to convert an active TCP socket into an SMC socket by modifying the underlying `struct file`, dentry, and inode in-place, which violates core VFS invariants that assume these structures are immutable for an open file, creating a risk of use after free errors and general system instability. Given the severity of this design flaw and the fact that cleaner alternatives (e.g., LD_PRELOAD, BPF) exist for legacy application transparency, the correct course of action is to remove this feature entirely.
https://git.kernel.org/stable/c/df31a6b0a3057e66994ad6ccf5d95b9b9514f033
https://git.kernel.org/stable/c/dc824ffc28e5c9d0020b6bee2651b4aceed5b2bf
https://git.kernel.org/stable/c/dc24e03be0e4bb2aad1a9b272c4f86de3b11969a
https://git.kernel.org/stable/c/74d33525db50d9d95156c79cc874752654e66e70
https://git.kernel.org/stable/c/6c505d95c69e27dbf28fea29dc84d2498d69515c