Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race on unaccepted mptcp sockets When the listener socket owning the relevant request is closed, it frees the unaccepted subflows and that causes later deletion of the paired MPTCP sockets. The mptcp socket's worker can run in the time interval between such delete operations. When that happens, any access to msk->first will cause an UaF access, as the subflow cleanup did not cleared such field in the mptcp socket. Address the issue explicitly traversing the listener socket accept queue at close time and performing the needed cleanup on the pending msk. Note that the locking is a bit tricky, as we need to acquire the msk socket lock, while still owning the subflow socket one.

Weaknesses 1

Affected Products 5

References 2

• git.kernel.org https://git.kernel.org/stable/c/6aeed9045071f2252ff4e98fc13d1e304f33e5b0
  Patch
• git.kernel.org https://git.kernel.org/stable/c/a8a3e95c74e48c2c9b07b81fafda9122993f2e12
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/6aeed9045071f2252ff4e98fc13d1e304f33e5b0
  Patch
• git.kernel.org https://git.kernel.org/stable/c/a8a3e95c74e48c2c9b07b81fafda9122993f2e12
  Patch