In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Clear association…

Why it is Yellow

• CVSS 7.8 high
• On your watchlist: linux kernel

References

• https://git.kernel.org/stable/c/030306bbb9273af80f14d7af20129661964cd9a7
• https://git.kernel.org/stable/c/32cd87f54dd1070020e664ccb0312a9f0fea79b4
• https://git.kernel.org/stable/c/9dcc0f4e488b70cff81e0e5717a498c929cf5de3
• https://git.kernel.org/stable/c/ad50d19f3d1ce052b3a146143581e930a1efb33e
• https://git.kernel.org/stable/c/bfdc744bf20ae4c3ef2e470298de5237c5c9a13c
• https://git.kernel.org/stable/c/df2584750314336edcbcc21fb388e04b260f35b7
• https://git.kernel.org/stable/c/e3f039082856adab7e195dea1af45d93dd6a3f1c
• https://git.kernel.org/stable/c/f11e09fe2fc3a11ccdf8f932b68181b0bb1d2078

Original description

In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Clear association under lock if siw_qp_modify fails in siw_accept We need to clear cep before release state_lock as siw_qp_llp_close and siw_qp_modify->siw_qp_llp_close did. Otherwise if siw_qp_modify() fails in siw_accept(), the QP's state_lock is released before the error path cleanup. A concurrent ibv_modify_qp() transitioning the QP to ERROR can race in this window: siw_accept() ibv_modify_qp(ERROR) ---------------------- ---------------------- siw_qp_modify() fails up_write(&qp->state_lock) down_write(&qp->state_lock) nextstate_from_idle(): if (qp->cep) siw_cep_put(qp->cep) <- frees cep qp->cep = NULL goto error cep->qp = NULL <- UAF Clear qp->cep and drop the association reference taken by siw_cep_get(), all under the write lock held from the initial down_write(&qp->state_lock). Thread B therefore sees qp->cep == NULL, skips its own put, and cannot free the cep before siw_accept() is done with it.