1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
http://git.qemu.org/?p=qemu.git;a=patch;h=765a707000e838c30b18d712fe6cb3dd8e0435f3
this patch is from qemu-git.
From 765a707000e838c30b18d712fe6cb3dd8e0435f3 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 2 Jan 2017 11:03:33 +0100
Subject: [PATCH] megasas: fix guest-triggered memory leak
If the guest sets the sglist size to a value >=2GB, megasas_handle_dcmd
will return MFI_STAT_MEMORY_NOT_AVAILABLE without freeing the memory.
Avoid this by returning only the status from map_dcmd, and loading
cmd->iov_size in the caller.
Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/scsi/megasas.c | 11 ++++++-----
1 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index 67fc1e7..6233865 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -683,14 +683,14 @@ static int megasas_map_dcmd(MegasasState *s, MegasasCmd *cmd)
trace_megasas_dcmd_invalid_sge(cmd->index,
cmd->frame->header.sge_count);
cmd->iov_size = 0;
- return -1;
+ return -EINVAL;
}
iov_pa = megasas_sgl_get_addr(cmd, &cmd->frame->dcmd.sgl);
iov_size = megasas_sgl_get_len(cmd, &cmd->frame->dcmd.sgl);
pci_dma_sglist_init(&cmd->qsg, PCI_DEVICE(s), 1);
qemu_sglist_add(&cmd->qsg, iov_pa, iov_size);
cmd->iov_size = iov_size;
- return cmd->iov_size;
+ return 0;
}
static void megasas_finish_dcmd(MegasasCmd *cmd, uint32_t iov_size)
@@ -1559,19 +1559,20 @@ static const struct dcmd_cmd_tbl_t {
static int megasas_handle_dcmd(MegasasState *s, MegasasCmd *cmd)
{
- int opcode, len;
+ int opcode;
int retval = 0;
+ size_t len;
const struct dcmd_cmd_tbl_t *cmdptr = dcmd_cmd_tbl;
opcode = le32_to_cpu(cmd->frame->dcmd.opcode);
trace_megasas_handle_dcmd(cmd->index, opcode);
- len = megasas_map_dcmd(s, cmd);
- if (len < 0) {
+ if (megasas_map_dcmd(s, cmd) < 0) {
return MFI_STAT_MEMORY_NOT_AVAILABLE;
}
while (cmdptr->opcode != -1 && cmdptr->opcode != opcode) {
cmdptr++;
}
+ len = cmd->iov_size;
if (cmdptr->opcode == -1) {
trace_megasas_dcmd_unhandled(cmd->index, opcode, len);
retval = megasas_dcmd_dummy(s, cmd);
--
1.7.0.4
|