From 13eb1e21d6198c9068eab7e7cb68c6d5c6834d1b Mon Sep 17 00:00:00 2001 From: Andrew Boyer Date: Mon, 28 Aug 2017 16:11:58 -0400 Subject: [PATCH] IB/rxe: Avoid ICRC errors by copying into the skb first The current process is to first calculate the CRC and then copy the client data into the packet. This leaves a window in which the packet contents and CRC can get out of sync, if the client changes the data after the CRC is calculated but before the data is copied. By copying the data into the packet and then calculating the CRC directly from the packet contents we eliminate the window. This can be seen with qperf's ud_bi_bw test. This seems like very strange/reckless client behavior, but whether the client has mangled its data or not RXE should be able to transfer it reliably. Fixes: 8700e3e7c485 ("Soft RoCE driver") Signed-off-by: Andrew Boyer Signed-off-by: Doug Ledford --- drivers/infiniband/sw/rxe/rxe_mr.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c index e37cc89987e1..5c2684bf430f 100644 --- a/drivers/infiniband/sw/rxe/rxe_mr.c +++ b/drivers/infiniband/sw/rxe/rxe_mr.c @@ -367,11 +367,11 @@ int rxe_mem_copy(struct rxe_mem *mem, u64 iova, void *addr, int length, dest = (dir == to_mem_obj) ? ((void *)(uintptr_t)iova) : addr; + memcpy(dest, src, length); + if (crcp) *crcp = rxe_crc32(to_rdev(mem->pd->ibpd.device), - *crcp, src, length); - - memcpy(dest, src, length); + *crcp, dest, length); return 0; } @@ -401,11 +401,11 @@ int rxe_mem_copy(struct rxe_mem *mem, u64 iova, void *addr, int length, if (bytes > length) bytes = length; + memcpy(dest, src, bytes); + if (crcp) crc = rxe_crc32(to_rdev(mem->pd->ibpd.device), - crc, src, bytes); - - memcpy(dest, src, bytes); + crc, dest, bytes); length -= bytes; addr += bytes; -- 2.30.2