From fe38562dbebfd02a6f0ca77af37bba642e5bb0f7 Mon Sep 17 00:00:00 2001 From: Darius Rad Date: Tue, 22 May 2018 16:38:57 -0400 Subject: [PATCH] Avoid dereferencing NULL pointer. If a NULL pointer is passed, don't attempt to increment it. This avoids passing the now not-NULL pointer on and eventually segfaulting. Also remove some unnecessary temporary variables. Change-Id: I268e225121aa283d59179bfae407ebf6959d3a4e Signed-off-by: Darius Rad Reviewed-on: http://openocd.zylin.com/4550 Tested-by: jenkins Reviewed-by: Andreas Fritiofson --- src/jtag/drivers/jtag_vpi.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/src/jtag/drivers/jtag_vpi.c b/src/jtag/drivers/jtag_vpi.c index a1787d496..1a42b3a05 100644 --- a/src/jtag/drivers/jtag_vpi.c +++ b/src/jtag/drivers/jtag_vpi.c @@ -204,23 +204,20 @@ static int jtag_vpi_queue_tdi_xfer(uint8_t *bits, int nb_bits, int tap_shift) static int jtag_vpi_queue_tdi(uint8_t *bits, int nb_bits, int tap_shift) { int nb_xfer = DIV_ROUND_UP(nb_bits, XFERT_MAX_SIZE * 8); - uint8_t *xmit_buffer = bits; - int xmit_nb_bits = nb_bits; - int i = 0; int retval; while (nb_xfer) { - if (nb_xfer == 1) { - retval = jtag_vpi_queue_tdi_xfer(&xmit_buffer[i], xmit_nb_bits, tap_shift); + retval = jtag_vpi_queue_tdi_xfer(bits, nb_bits, tap_shift); if (retval != ERROR_OK) return retval; } else { - retval = jtag_vpi_queue_tdi_xfer(&xmit_buffer[i], XFERT_MAX_SIZE * 8, NO_TAP_SHIFT); + retval = jtag_vpi_queue_tdi_xfer(bits, XFERT_MAX_SIZE * 8, NO_TAP_SHIFT); if (retval != ERROR_OK) return retval; - xmit_nb_bits -= XFERT_MAX_SIZE * 8; - i += XFERT_MAX_SIZE; + nb_bits -= XFERT_MAX_SIZE * 8; + if (bits) + bits += XFERT_MAX_SIZE; } nb_xfer--;