clear i_sends on setup unwind

Summary

In the Linux kernel, the following vulnerability has been resolved: net: rds: clear i_sends on setup unwind The RDS IB connection teardown path is written so it can run during partial startup and on repeated shutdown attempts. It uses NULL pointers to distinguish resources that are still owned from resources that have already been released. When rds_ib_setup_qp() fails after allocating i_sends but before allocating i_recvs, the sends_out path frees i_sends without clearing the pointer. A later shutdown pass can still treat that stale pointer as a live send ring allocation. Clear i_sends after vfree() in the error unwind path so the existing shutdown logic continues to use the correct ownership state. A flaw was found in the Linux kernel's Reliable Datagram Sockets (RDS) over InfiniBand (IB) connection teardown process. When the rds_ib_setup_qp() function fails to set up a connection, it may free a memory allocation (i_sends) without properly clearing the associated pointer. This can lead to a stale pointer being used in a subsequent shutdown operation, potentially causing incorrect memory access and system instability or a denial of service. Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-825. Affected Red Hat products: Red Hat Enterprise Linux 6. Will not fix / out of support: Red Hat Enterprise Linux 6.