diff options
Diffstat (limited to 'drivers/mtd/ubi/scan.c')
| -rw-r--r-- | drivers/mtd/ubi/scan.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c index c3d653ba5ca..b847745394b 100644 --- a/drivers/mtd/ubi/scan.c +++ b/drivers/mtd/ubi/scan.c @@ -757,6 +757,8 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, si->is_empty = 0; if (!ec_corr) { + int image_seq; + /* Make sure UBI version is OK */ if (ech->version != UBI_VERSION) { ubi_err("this UBI version is %d, image version is %d", @@ -778,6 +780,29 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, ubi_dbg_dump_ec_hdr(ech); return -EINVAL; } + + /* + * Make sure that all PEBs have the same image sequence number. + * This allows us to detect situations when users flash UBI + * images incorrectly, so that the flash has the new UBI image + * and leftovers from the old one. This feature was added + * relatively recently, and the sequence number was always + * zero, because old UBI implementations always set it to zero. + * For this reasons, we do not panic if some PEBs have zero + * sequence number, while other PEBs have non-zero sequence + * number. + */ + image_seq = be32_to_cpu(ech->image_seq); + if (!si->image_seq_set) { + ubi->image_seq = image_seq; + si->image_seq_set = 1; + } else if (ubi->image_seq && ubi->image_seq != image_seq) { + ubi_err("bad image sequence number %d in PEB %d, " + "expected %d", image_seq, pnum, ubi->image_seq); + ubi_dbg_dump_ec_hdr(ech); + return -EINVAL; + } + } /* OK, we've done with the EC header, let's look at the VID header */ |