From 993e162d4f0ae2c0719999b8fb7e6e3418f173d3 Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Wed, 5 Dec 2018 13:26:20 +0100 Subject: [PATCH] dediprog: Fix small, unaligned reads This never was a use case until now but the `--fmap` code makes it obvious: Unaligned reads that were smaller than the `chunksize` here, were extended without considering the length of the buffer read into. With that fixed we run into the next problem: dediprog_spi_bulk_read() shouldn't report an error when an empty read is unaligned. Change-Id: Ie12b62499ebfdb467d5126c00d327c76077ddead Signed-off-by: Nico Huber Reviewed-on: https://review.coreboot.org/c/30051 Tested-by: build bot (Jenkins) Reviewed-by: David Hendricks Reviewed-on: https://review.coreboot.org/c/30380 Reviewed-by: Nico Huber --- dediprog.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/dediprog.c b/dediprog.c index 2f5b441fe..70660d48e 100644 --- a/dediprog.c +++ b/dediprog.c @@ -425,15 +425,15 @@ static int dediprog_spi_bulk_read(struct flashctx *flash, uint8_t *buf, unsigned struct libusb_transfer *transfers[DEDIPROG_ASYNC_TRANSFERS] = { NULL, }; struct libusb_transfer *transfer; + if (len == 0) + return 0; + if ((start % chunksize) || (len % chunksize)) { msg_perr("%s: Unaligned start=%i, len=%i! Please report a bug at flashrom@flashrom.org\n", __func__, start, len); return 1; } - if (len == 0) - return 0; - /* Command packet size of protocols: new 10 B, old 5 B. */ uint8_t data_packet[is_new_prot() ? 10 : 5]; unsigned int value, idx; @@ -503,7 +503,7 @@ static int dediprog_spi_read(struct flashctx *flash, uint8_t *buf, unsigned int int ret; /* chunksize must be 512, other sizes will NOT work at all. */ const unsigned int chunksize = 0x200; - unsigned int residue = start % chunksize ? chunksize - start % chunksize : 0; + unsigned int residue = start % chunksize ? min(len, chunksize - start % chunksize) : 0; unsigned int bulklen; dediprog_set_leds(LED_BUSY);