From 92874fa6a7dd60c5a6451816992c2ad41aa3a7a7 Mon Sep 17 00:00:00 2001 From: Nikolai Artemiev Date: Fri, 9 Dec 2022 15:23:08 +1100 Subject: flashrom: Check for flash access restricitons in verify_range() Make verify_flash() skip read/write-protected regions based on the FLASHROM_FLAG_SKIP_UNREADABLE and FLASHROM_FLAG_SKIP_UNWRITABLE flags. If FLASHROM_FLAG_SKIP_UNREADABLE is false, read-protected regions will cause verification to fail. If FLASHROM_FLAG_SKIP_UNWRITABLE is false, read-only regions will still be verified and any mismatch will cause verification to fail. It can be useful to set the flag to true so that expected mismatches in read-only regions are ignored by verify_range() after flashing. BUG=b:260440773 BRANCH=none TEST=flashrom -v on dedede (JSL) Change-Id: I61dfadd3c75365f2e55abeea75f673ab791ca5cc CoAuthored-by: Edward O'Callaghan Signed-off-by: Edward O'Callaghan Signed-off-by: Nikolai Artemiev Reviewed-on: https://review.coreboot.org/c/flashrom/+/70515 Reviewed-by: Edward O'Callaghan Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons --- flashrom.c | 48 +++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 41 insertions(+), 7 deletions(-) (limited to 'flashrom.c') diff --git a/flashrom.c b/flashrom.c index d036b5c7e..573f10b39 100644 --- a/flashrom.c +++ b/flashrom.c @@ -604,15 +604,49 @@ int verify_range(struct flashctx *flash, const uint8_t *cmpbuf, unsigned int sta return -1; } - int ret = read_flash(flash, readbuf, start, len); - if (ret) { - msg_gerr("Verification impossible because read failed " - "at 0x%x (len 0x%x)\n", start, len); - ret = -1; - goto out_free; + int ret = 0; + + msg_gdbg("%#06x..%#06x ", start, start + len - 1); + + unsigned int read_len; + for (size_t addr = start; addr < start + len; addr += read_len) { + struct flash_region region; + get_flash_region(flash, addr, ®ion); + read_len = min(start + len, region.end) - addr; + + if ((region.write_prot && flash->flags.skip_unwritable_regions) || + (region.read_prot && flash->flags.skip_unreadable_regions)) { + msg_gdbg("%s: Skipping verification of %s region (%#08x..%#08x)\n", + __func__, region.name, region.start, region.end - 1); + free(region.name); + continue; + } + + if (region.read_prot) { + msg_gerr("%s: Verification imposible because %s region (%#08x..%#08x) is unreadable.\n", + __func__, region.name, region.start, region.end - 1); + free(region.name); + goto out_free; + } + + msg_gdbg("%s: Verifying %s region (%#08x..%#08x)\n", + __func__, region.name, region.start, region.end - 1); + free(region.name); + + ret = read_flash(flash, readbuf, addr, read_len); + if (ret) { + msg_gerr("Verification impossible because read failed " + "at 0x%x (len 0x%x)\n", start, len); + ret = -1; + goto out_free; + } + + ret = compare_range(cmpbuf + (addr - start), readbuf, addr, read_len); + if (ret) + goto out_free; + } - ret = compare_range(cmpbuf, readbuf, start, len); out_free: free(readbuf); return ret; -- cgit v1.2.3