Patchwork [19/32] scsi-disk: improve the lba-out-of-range tests for read/write/verify

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Submitter Paolo Bonzini
Date July 27, 2012, 3:02 p.m.
Message ID <1343401379-19495-20-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/173716/
State New
Headers show

Comments

Paolo Bonzini - July 27, 2012, 3:02 p.m.
From: Ronnie Sahlberg <ronniesahlberg@gmail.com>

Improve the tests for the LBA to cover more cases.

For the 16 byte opcodes, the lba is a uint64, so we need to check is to
make sure that we do not wrap.  For example if an opcode would specify
the LBA:0xffffffffffffffff and LEN:2 then lba+len would wrap to 1.

Also verify that ALL requested blocks are available, not just the first one.

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/scsi-disk.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Patch

diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index 526da4b..3c03159 100644
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -1777,7 +1777,8 @@  static int32_t scsi_disk_dma_command(SCSIRequest *req, uint8_t *buf)
         if (r->req.cmd.buf[1] & 0xe0) {
             goto illegal_request;
         }
-        if (r->req.cmd.lba > s->qdev.max_lba) {
+        if (r->req.cmd.lba > r->req.cmd.lba + len ||
+            r->req.cmd.lba + len - 1 > s->qdev.max_lba) {
             goto illegal_lba;
         }
         r->sector = r->req.cmd.lba * (s->qdev.blocksize / 512);
@@ -1800,7 +1801,8 @@  static int32_t scsi_disk_dma_command(SCSIRequest *req, uint8_t *buf)
         if (r->req.cmd.buf[1] & 0xe0) {
             goto illegal_request;
         }
-        if (r->req.cmd.lba > s->qdev.max_lba) {
+        if (r->req.cmd.lba > r->req.cmd.lba + len ||
+            r->req.cmd.lba + len - 1 > s->qdev.max_lba) {
             goto illegal_lba;
         }
         r->sector = r->req.cmd.lba * (s->qdev.blocksize / 512);