The branch main has been updated by jhb:
URL:
https://cgit.FreeBSD.org/src/commit/?id=cf57f20edcf9c75f0f9f1ac1c44729184970b9d9
commit cf57f20edcf9c75f0f9f1ac1c44729184970b9d9
Author: John Baldwin <j...@freebsd.org>
AuthorDate: 2023-01-20 17:58:38 +0000
Commit: John Baldwin <j...@freebsd.org>
CommitDate: 2023-01-20 17:58:38 +0000
bhyve: Fix a buffer overread in the PCI hda device model.
The sc->codecs array contains HDA_CODEC_MAX (15) entries. The
guest-supplied cad field in the verb provided to hda_send_command is a
4-bit field that was used as an index into sc->codecs without any
bounds checking. The highest value (15) would overflow the array.
Other uses of sc->codecs in the device model used sc->codecs_no to
determine which array indices have been initialized, so use a similar
check to reject requests for uninitialized or invalid cad indices in
hda_send_command.
PR: 264582
Reported by: Robert Morris <r...@lcs.mit.edu>
Reviewed by: corvink, markj, emaste
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38128
---
usr.sbin/bhyve/pci_hda.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/usr.sbin/bhyve/pci_hda.c b/usr.sbin/bhyve/pci_hda.c
index bb8fba1a54bb..9e9d7ab5a626 100644
--- a/usr.sbin/bhyve/pci_hda.c
+++ b/usr.sbin/bhyve/pci_hda.c
@@ -475,12 +475,14 @@ hda_send_command(struct hda_softc *sc, uint32_t verb)
struct hda_codec_class *codec = NULL;
uint8_t cad = (verb >> HDA_CMD_CAD_SHIFT) & 0x0f;
- hci = sc->codecs[cad];
- if (!hci)
+ if (cad >= sc->codecs_no)
return (-1);
DPRINTF("cad: 0x%x verb: 0x%x", cad, verb);
+ hci = sc->codecs[cad];
+ assert(hci);
+
codec = hci->codec;
assert(codec);
