Andrew Geissler | b7d2861 | 2020-07-24 16:15:54 -0500 | [diff] [blame] | 1 | From f50ab86a2620bd7e8507af865b164655ee921661 Mon Sep 17 00:00:00 2001 |
| 2 | From: Prasad J Pandit <pjp@fedoraproject.org> |
| 3 | Date: Thu, 14 May 2020 00:55:38 +0530 |
| 4 | Subject: [PATCH] megasas: use unsigned type for reply_queue_head and check |
| 5 | index |
| 6 | |
| 7 | A guest user may set 'reply_queue_head' field of MegasasState to |
| 8 | a negative value. Later in 'megasas_lookup_frame' it is used to |
| 9 | index into s->frames[] array. Use unsigned type to avoid OOB |
| 10 | access issue. |
| 11 | |
| 12 | Also check that 'index' value stays within s->frames[] bounds |
| 13 | through the while() loop in 'megasas_lookup_frame' to avoid OOB |
| 14 | access. |
| 15 | |
| 16 | Reported-by: Ren Ding <rding@gatech.edu> |
| 17 | Reported-by: Hanqing Zhao <hanqing@gatech.edu> |
| 18 | Reported-by: Alexander Bulekov <alxndr@bu.edu> |
| 19 | Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> |
| 20 | Acked-by: Alexander Bulekov <alxndr@bu.edu> |
| 21 | Message-Id: <20200513192540.1583887-2-ppandit@redhat.com> |
| 22 | Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
| 23 | |
| 24 | Upstream-Status: Backport [f50ab86a2620bd7e8507af865b164655ee921661] |
| 25 | CVE: CVE-2020-13362 |
| 26 | Signed-off-by: Sakib Sajal <sakib.sajal@windriver.com> |
| 27 | --- |
| 28 | hw/scsi/megasas.c | 4 ++-- |
| 29 | 1 file changed, 2 insertions(+), 2 deletions(-) |
| 30 | |
| 31 | diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c |
| 32 | index af18c88b65..6ce598cd69 100644 |
| 33 | --- a/hw/scsi/megasas.c |
| 34 | +++ b/hw/scsi/megasas.c |
| 35 | @@ -112,7 +112,7 @@ typedef struct MegasasState { |
| 36 | uint64_t reply_queue_pa; |
| 37 | void *reply_queue; |
| 38 | int reply_queue_len; |
| 39 | - int reply_queue_head; |
| 40 | + uint16_t reply_queue_head; |
| 41 | int reply_queue_tail; |
| 42 | uint64_t consumer_pa; |
| 43 | uint64_t producer_pa; |
| 44 | @@ -445,7 +445,7 @@ static MegasasCmd *megasas_lookup_frame(MegasasState *s, |
| 45 | |
| 46 | index = s->reply_queue_head; |
| 47 | |
| 48 | - while (num < s->fw_cmds) { |
| 49 | + while (num < s->fw_cmds && index < MEGASAS_MAX_FRAMES) { |
| 50 | if (s->frames[index].pa && s->frames[index].pa == frame) { |
| 51 | cmd = &s->frames[index]; |
| 52 | break; |
| 53 | -- |
| 54 | 2.20.1 |
| 55 | |