ahci: check for ncq prdtl overflow

Don't attempt the NCQ transfer if the PRDT we were given is not big
enough to perform the entire transfer.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1435016308-6150-5-git-send-email-jsnow@redhat.com
This commit is contained in:
John Snow 2015-07-04 02:06:03 -04:00
parent a55c8231d0
commit 3bcbe4aa80

View file

@ -983,6 +983,7 @@ static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
NCQFrame *ncq_fis = (NCQFrame*)cmd_fis;
uint8_t tag = ncq_fis->tag >> 3;
NCQTransferState *ncq_tfs = &ad->ncq_tfs[tag];
size_t size;
if (ncq_tfs->used) {
/* error - already in use */
@ -999,20 +1000,28 @@ static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
((uint64_t)ncq_fis->lba2 << 16) |
((uint64_t)ncq_fis->lba1 << 8) |
(uint64_t)ncq_fis->lba0;
ncq_tfs->tag = tag;
/* Note: We calculate the sector count, but don't currently rely on it.
* The total size of the DMA buffer tells us the transfer size instead. */
ncq_tfs->sector_count = ((uint16_t)ncq_fis->sector_count_high << 8) |
ncq_fis->sector_count_low;
ahci_populate_sglist(ad, &ncq_tfs->sglist, 0);
size = ncq_tfs->sector_count * 512;
if (ncq_tfs->sglist.size < size) {
error_report("ahci: PRDT length for NCQ command (0x%zx) "
"is smaller than the requested size (0x%zx)",
ncq_tfs->sglist.size, size);
qemu_sglist_destroy(&ncq_tfs->sglist);
ncq_err(ncq_tfs);
ahci_trigger_irq(ad->hba, ad, PORT_IRQ_OVERFLOW);
return;
}
DPRINTF(port, "NCQ transfer LBA from %"PRId64" to %"PRId64", "
"drive max %"PRId64"\n",
ncq_tfs->lba, ncq_tfs->lba + ncq_tfs->sector_count - 2,
ide_state->nb_sectors - 1);
ahci_populate_sglist(ad, &ncq_tfs->sglist, 0);
ncq_tfs->tag = tag;
switch(ncq_fis->command) {
case READ_FPDMA_QUEUED:
DPRINTF(port, "NCQ reading %d sectors from LBA %"PRId64", "
@ -1051,6 +1060,7 @@ static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
"error: tried to process non-NCQ command as NCQ\n");
}
qemu_sglist_destroy(&ncq_tfs->sglist);
ncq_err(ncq_tfs);
}
}