scsi: lpfc: Fix buffer free/clear order in deferred receive path

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix buffer free/clear order in deferred receive path Fix a use-after-free window by correcting the buffer release sequence in the deferred receive path. The code freed the RQ buffer first and only then cleared the context pointer under the lock. Concurrent paths (e.g., ABTS and the repost path) also inspect and release the same pointer under the lock, so the old order could lead to double-free/UAF. Note that the repost path already uses the correct pattern: detach the pointer under the lock, then free it after dropping the lock. The deferred path should do the same.

References

• https://git.kernel.org/stable/c/ab34084f42ee06a9028d67c78feafb911d33d111
• https://git.kernel.org/stable/c/baa39f6ad79d372a6ce0aa639fbb2f1578479f57
• https://git.kernel.org/stable/c/95b63d15fce5c54a73bbf195e1aacb5a75b128e2
• https://git.kernel.org/stable/c/55658c7501467ca9ef3bd4453dd920010db8bc13
• https://git.kernel.org/stable/c/d96cc9a1b57725930c60b607423759d563b4d900
• https://git.kernel.org/stable/c/367cb5ffd8a8a4c85dc89f55e7fa7cc191425b11
• https://git.kernel.org/stable/c/897f64b01c1249ac730329b83f4f40bab71e86c7
• https://git.kernel.org/stable/c/9dba9a45c348e8460da97c450cddf70b2056deb3