From: Bernard Metzler bmt@zurich.ibm.com

stable inclusion from stable-v5.10.198 commit 0d520cdb0cd095eac5d00078dfd318408c9b5eed category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I987V5

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit 53a3f777049771496f791504e7dc8ef017cba590 upstream.

In case immediate MPA request processing fails, the newly created endpoint unlinks the listening endpoint and is ready to be dropped. This special case was not handled correctly by the code handling the later TCP socket close, causing a NULL dereference crash in siw_cm_work_handler() when dereferencing a NULL listener. We now also cancel the useless MPA timeout, if immediate MPA request processing fails.

This patch furthermore simplifies MPA processing in general: Scheduling a useless TCP socket read in sk_data_ready() upcall is now surpressed, if the socket is already moved out of TCP_ESTABLISHED state.

Fixes: 6c52fdc244b5 ("rdma/siw: connection management") Signed-off-by: Bernard Metzler bmt@zurich.ibm.com Link: https://lore.kernel.org/r/20230905145822.446263-1-bmt@zurich.ibm.com Signed-off-by: Leon Romanovsky leon@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: sanglipeng sanglipeng1@jd.com --- drivers/infiniband/sw/siw/siw_cm.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c index b87ba4c9fccf..bfa163de6d06 100644 --- a/drivers/infiniband/sw/siw/siw_cm.c +++ b/drivers/infiniband/sw/siw/siw_cm.c @@ -973,6 +973,7 @@ static void siw_accept_newconn(struct siw_cep *cep) siw_cep_put(cep); new_cep->listen_cep = NULL; if (rv) { + siw_cancel_mpatimer(new_cep); siw_cep_set_free(new_cep); goto error; } @@ -1097,9 +1098,12 @@ static void siw_cm_work_handler(struct work_struct *w) /* * Socket close before MPA request received. */ - siw_dbg_cep(cep, "no mpareq: drop listener\n"); - siw_cep_put(cep->listen_cep); - cep->listen_cep = NULL; + if (cep->listen_cep) { + siw_dbg_cep(cep, + "no mpareq: drop listener\n"); + siw_cep_put(cep->listen_cep); + cep->listen_cep = NULL; + } } } release_cep = 1; @@ -1222,7 +1226,11 @@ static void siw_cm_llp_data_ready(struct sock *sk) if (!cep) goto out;

- siw_dbg_cep(cep, "state: %d\n", cep->state); + siw_dbg_cep(cep, "cep state: %d, socket state %d\n", + cep->state, sk->sk_state); + + if (sk->sk_state != TCP_ESTABLISHED) + goto out;

switch (cep->state) { case SIW_EPSTATE_RDMA_MODE: