Commit 6395fe0c authored by Peter Maydell's avatar Peter Maydell
Browse files

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging 



Pull request

Bug fixes for the .dmg image file format.

# gpg: Signature made Fri 04 Jan 2019 11:21:18 GMT
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  dmg: don't skip zero chunk
  dmg: use enumeration type instead of hard coding number
  dmg: fix binary search
  dmg: Fixing wrong dmg block type value for block terminator.

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parents 8ecede46 39a0408e

block/dmg.c

+20 −11
Original line number Diff line number Diff line
@@ -54,7 +54,7 @@ enum { 
    UDBZ,

    ULFO,

    UDCM = 0x7ffffffe, /* Comments */

    UDLE               /* Last Entry */

    UDLE = 0xffffffff  /* Last Entry */

};



static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
@@ -130,7 +130,8 @@ static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk, 
    case UDRW: /* copy */

        uncompressed_sectors = DIV_ROUND_UP(s->lengths[chunk], 512);

        break;

    case UDIG: /* zero */

    case UDZE: /* zero */

    case UDIG: /* ignore */

        /* as the all-zeroes block may be large, it is treated specially: the

         * sector is not copied from a large buffer, a simple memset is used

         * instead. Therefore uncompressed_sectors does not need to be set. */
@@ -199,8 +200,9 @@ typedef struct DmgHeaderState { 
static bool dmg_is_known_block_type(uint32_t entry_type)

{

    switch (entry_type) {

    case UDZE:    /* zeros */

    case UDRW:    /* uncompressed */

    case UDIG:    /* zeroes */

    case UDIG:    /* ignore */

    case UDZO:    /* zlib */

        return true;

    case UDBZ:    /* bzip2 */
@@ -265,9 +267,10 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, 
        /* sector count */

        s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10);



        /* all-zeroes sector (type 2) does not need to be "uncompressed" and can

         * therefore be unbounded. */

        if (s->types[i] != 2 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {

        /* all-zeroes sector (type UDZE and UDIG) does not need to be

         * "uncompressed" and can therefore be unbounded. */

        if (s->types[i] != UDZE && s->types[i] != UDIG

            && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {

            error_report("sector count %" PRIu64 " for chunk %" PRIu32

                         " is larger than max (%u)",

                         s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
@@ -572,16 +575,20 @@ static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num) 
{

    /* binary search */

    uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;

    while (chunk1 != chunk2) {

    while (chunk1 <= chunk2) {

        chunk3 = (chunk1 + chunk2) / 2;

        if (s->sectors[chunk3] > sector_num) {

            chunk2 = chunk3;

            if (chunk3 == 0) {

                goto err;

            }

            chunk2 = chunk3 - 1;

        } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {

            return chunk3;

        } else {

            chunk1 = chunk3;

            chunk1 = chunk3 + 1;

        }

    }

err:

    return s->n_chunks; /* error */

}
@@ -671,7 +678,8 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num) 
                return -1;

            }

            break;

        case UDIG: /* zero */

        case UDZE: /* zeros */

        case UDIG: /* ignore */

            /* see dmg_read, it is treated specially. No buffer needs to be

             * pre-filled, the zeroes can be set directly. */

            break;
@@ -706,7 +714,8 @@ dmg_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, 
        /* Special case: current chunk is all zeroes. Do not perform a memcpy as

         * s->uncompressed_chunk may be too small to cover the large all-zeroes

         * section. dmg_read_chunk is called to find s->current_chunk */

        if (s->types[s->current_chunk] == 2) { /* all zeroes block entry */

        if (s->types[s->current_chunk] == UDZE

            || s->types[s->current_chunk] == UDIG) { /* all zeroes block entry */

            qemu_iovec_memset(qiov, i * 512, 0, 512);

            continue;

        }