From 819cd3281d9003b950005b22a05978625cb73296 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marek=20Beh=C3=BAn?= Date: Fri, 24 Sep 2021 23:06:53 +0200 Subject: [PATCH] tools: kwboot: Prevent waiting indefinitely if no xmodem reply is received MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Currently if BootROM fails to respond with ACK/NAK to a xmodem block, we will be waiting indefinitely for such response. Make sure that we only wait at most 1 second (blk_rsp_timeo) for ACK/NAK for each block in case non-xmodem text output is not being expected. Interpret this timeout expiration as NAK, to try to send the block again. On the other hand, if timeout expires without ACK while some non-xmodem output was already received (DDR training output, for example), we know that the block was received, since the code is being executed, so in this case exit with ETIMEDOUT. Signed-off-by: Marek Behún Reviewed-by: Stefan Roese --- tools/kwboot.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/tools/kwboot.c b/tools/kwboot.c index cf6e32c6fa..8c11dca5ed 100644 --- a/tools/kwboot.c +++ b/tools/kwboot.c @@ -407,17 +407,18 @@ static int kwboot_xm_recv_reply(int fd, char *c, int allow_non_xm, int *non_xm_print) { int timeout = allow_non_xm ? KWBOOT_HDR_RSP_TIMEO : blk_rsp_timeo; - uint64_t recv_until = 0; + uint64_t recv_until = _now() + timeout; int rc; - *non_xm_print = 0; + if (non_xm_print) + *non_xm_print = 0; while (1) { rc = kwboot_tty_recv(fd, c, 1, timeout); if (rc) { if (errno != ETIMEDOUT) return rc; - else if (recv_until && recv_until < _now()) + else if (allow_non_xm && *non_xm_print) return -1; else *c = NAK; @@ -430,12 +431,19 @@ kwboot_xm_recv_reply(int fd, char *c, int allow_non_xm, int *non_xm_print) /* * If printing non-xmodem text output is allowed and such a byte * was received, print it and increase receiving time. + * Otherwise decrease timeout by time elapsed. */ if (allow_non_xm) { recv_until = _now() + timeout; putchar(*c); fflush(stdout); *non_xm_print = 1; + } else { + timeout = recv_until - _now(); + if (timeout < 0) { + errno = ETIMEDOUT; + return -1; + } } } -- 2.39.5