From: David Woodhouse [MTD] Fix regression in RedBoot partition scanning This fixes a regression introduced by the attempt to handle RedBoot FIS tables which are smaller than an eraseblock, in commit 0b47d654089c5ce3f2ea26a4485db9bcead1e515 It moves the recalculation of the number of slots in the table to the correct place, and improves the heuristic for when we think we need to byte-swap what we read from the flash. Signed-off-by: David Woodhouse Cc: Rod Whitby Signed-off-by: Greg Kroah-Hartman --- drivers/mtd/redboot.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) --- linux-2.6.20.1.orig/drivers/mtd/redboot.c +++ linux-2.6.20.1/drivers/mtd/redboot.c @@ -94,8 +94,19 @@ static int parse_redboot_partitions(stru * (NOTE: this is 'size' not 'data_length'; size is * the full size of the entry.) */ - if (swab32(buf[i].size) == master->erasesize) { + + /* RedBoot can combine the FIS directory and + config partitions into a single eraseblock; + we assume wrong-endian if either the swapped + 'size' matches the eraseblock size precisely, + or if the swapped size actually fits in an + eraseblock while the unswapped size doesn't. */ + if (swab32(buf[i].size) == master->erasesize || + (buf[i].size > master->erasesize + && swab32(buf[i].size) < master->erasesize)) { int j; + /* Update numslots based on actual FIS directory size */ + numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc); for (j = 0; j < numslots; ++j) { /* A single 0xff denotes a deleted entry. @@ -120,11 +131,11 @@ static int parse_redboot_partitions(stru swab32s(&buf[j].desc_cksum); swab32s(&buf[j].file_cksum); } + } else if (buf[i].size < master->erasesize) { + /* Update numslots based on actual FIS directory size */ + numslots = buf[i].size / sizeof(struct fis_image_desc); } break; - } else { - /* re-calculate of real numslots */ - numslots = buf[i].size / sizeof(struct fis_image_desc); } } if (i == numslots) { -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/