[qemu/f20] Fix SLES11 migration issue (bz #1109427) CVE-2014-7840: insufficient parameter validation during ram
Cole Robinson
crobinso at fedoraproject.org
Sun Nov 30 23:12:21 UTC 2014
commit 56715e285b6128fe0a9fbf9a38ce445d908d0119
Author: Cole Robinson <crobinso at redhat.com>
Date: Sun Nov 30 18:12:22 2014 -0500
Fix SLES11 migration issue (bz #1109427)
CVE-2014-7840: insufficient parameter validation during ram load (bz #1163080)
...sure-time-in-migration-never-goes-backwar.patch | 98 ++++++++++++++++++++
...sure-proper-env-tsc-value-for-kvmclock_cu.patch | 42 +++++++++
...tion-fix-parameter-validation-on-ram-load.patch | 56 +++++++++++
qemu.spec | 19 ++++-
4 files changed, 214 insertions(+), 1 deletions(-)
---
diff --git a/0419-kvmclock-Ensure-time-in-migration-never-goes-backwar.patch b/0419-kvmclock-Ensure-time-in-migration-never-goes-backwar.patch
new file mode 100644
index 0000000..5d1739a
--- /dev/null
+++ b/0419-kvmclock-Ensure-time-in-migration-never-goes-backwar.patch
@@ -0,0 +1,98 @@
+From: Alexander Graf <agraf at suse.de>
+Date: Fri, 5 Sep 2014 10:52:45 -0300
+Subject: [PATCH] kvmclock: Ensure time in migration never goes backward
+
+When we migrate we ask the kernel about its current belief on what the guest
+time would be. However, I've seen cases where the kvmclock guest structure
+indicates a time more recent than the kvm returned time.
+
+To make sure we never go backwards, calculate what the guest would have seen as time at the point of migration and use that value instead of the kernel returned one when it's more recent.
+This bases the view of the kvmclock after migration on the
+same foundation in host as well as guest.
+
+Signed-off-by: Alexander Graf <agraf at suse.de>
+Cc: qemu-stable at nongnu.org
+Reviewed-by: Marcelo Tosatti <mtosatti at redhat.com>
+Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>
+(cherry picked from commit 9a48bcd1b82494671c111109b0eefdb882581499)
+---
+ hw/i386/kvm/clock.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 49 insertions(+)
+
+diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c
+index e89e2f7..2fea4eb 100644
+--- a/hw/i386/kvm/clock.c
++++ b/hw/i386/kvm/clock.c
+@@ -14,6 +14,7 @@
+ */
+
+ #include "qemu-common.h"
++#include "qemu/host-utils.h"
+ #include "sysemu/sysemu.h"
+ #include "sysemu/kvm.h"
+ #include "hw/sysbus.h"
+@@ -34,6 +35,48 @@ typedef struct KVMClockState {
+ bool clock_valid;
+ } KVMClockState;
+
++struct pvclock_vcpu_time_info {
++ uint32_t version;
++ uint32_t pad0;
++ uint64_t tsc_timestamp;
++ uint64_t system_time;
++ uint32_t tsc_to_system_mul;
++ int8_t tsc_shift;
++ uint8_t flags;
++ uint8_t pad[2];
++} __attribute__((__packed__)); /* 32 bytes */
++
++static uint64_t kvmclock_current_nsec(KVMClockState *s)
++{
++ CPUState *cpu = first_cpu;
++ CPUX86State *env = cpu->env_ptr;
++ hwaddr kvmclock_struct_pa = env->system_time_msr & ~1ULL;
++ uint64_t migration_tsc = env->tsc;
++ struct pvclock_vcpu_time_info time;
++ uint64_t delta;
++ uint64_t nsec_lo;
++ uint64_t nsec_hi;
++ uint64_t nsec;
++
++ if (!(env->system_time_msr & 1ULL)) {
++ /* KVM clock not active */
++ return 0;
++ }
++
++ cpu_physical_memory_read(kvmclock_struct_pa, &time, sizeof(time));
++
++ assert(time.tsc_timestamp <= migration_tsc);
++ delta = migration_tsc - time.tsc_timestamp;
++ if (time.tsc_shift < 0) {
++ delta >>= -time.tsc_shift;
++ } else {
++ delta <<= time.tsc_shift;
++ }
++
++ mulu64(&nsec_lo, &nsec_hi, delta, time.tsc_to_system_mul);
++ nsec = (nsec_lo >> 32) | (nsec_hi << 32);
++ return nsec + time.system_time;
++}
+
+ static void kvmclock_vm_state_change(void *opaque, int running,
+ RunState state)
+@@ -45,9 +88,15 @@ static void kvmclock_vm_state_change(void *opaque, int running,
+
+ if (running) {
+ struct kvm_clock_data data;
++ uint64_t time_at_migration = kvmclock_current_nsec(s);
+
+ s->clock_valid = false;
+
++ /* We can't rely on the migrated clock value, just discard it */
++ if (time_at_migration) {
++ s->clock = time_at_migration;
++ }
++
+ data.clock = s->clock;
+ data.flags = 0;
+ ret = kvm_vm_ioctl(kvm_state, KVM_SET_CLOCK, &data);
diff --git a/0420-kvmclock-Ensure-proper-env-tsc-value-for-kvmclock_cu.patch b/0420-kvmclock-Ensure-proper-env-tsc-value-for-kvmclock_cu.patch
new file mode 100644
index 0000000..e939e46
--- /dev/null
+++ b/0420-kvmclock-Ensure-proper-env-tsc-value-for-kvmclock_cu.patch
@@ -0,0 +1,42 @@
+From: Marcelo Tosatti <mtosatti at redhat.com>
+Date: Fri, 5 Sep 2014 10:52:47 -0300
+Subject: [PATCH] kvmclock: Ensure proper env->tsc value for
+ kvmclock_current_nsec calculation
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Ensure proper env->tsc value for kvmclock_current_nsec calculation.
+
+Reported-by: Marcin Gibuła <m.gibula at beyond.pl>
+Analyzed-by: Marcin Gibuła <m.gibula at beyond.pl>
+Cc: qemu-stable at nongnu.org
+Signed-off-by: Marcelo Tosatti <mtosatti at redhat.com>
+Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>
+(cherry picked from commit 317b0a6d8ba44e9bf8f9c3dbd776c4536843d82c)
+---
+ hw/i386/kvm/clock.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c
+index 2fea4eb..eaf3f0a 100644
+--- a/hw/i386/kvm/clock.c
++++ b/hw/i386/kvm/clock.c
+@@ -17,6 +17,7 @@
+ #include "qemu/host-utils.h"
+ #include "sysemu/sysemu.h"
+ #include "sysemu/kvm.h"
++#include "sysemu/cpus.h"
+ #include "hw/sysbus.h"
+ #include "hw/kvm/clock.h"
+
+@@ -124,6 +125,9 @@ static void kvmclock_vm_state_change(void *opaque, int running,
+ if (s->clock_valid) {
+ return;
+ }
++
++ cpu_synchronize_all_states();
++ cpu_clean_all_dirty();
+ ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
+ if (ret < 0) {
+ fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret));
diff --git a/0421-migration-fix-parameter-validation-on-ram-load.patch b/0421-migration-fix-parameter-validation-on-ram-load.patch
new file mode 100644
index 0000000..758eabb
--- /dev/null
+++ b/0421-migration-fix-parameter-validation-on-ram-load.patch
@@ -0,0 +1,56 @@
+From: "Michael S. Tsirkin" <mst at redhat.com>
+Date: Wed, 12 Nov 2014 11:44:39 +0200
+Subject: [PATCH] migration: fix parameter validation on ram load
+
+During migration, the values read from migration stream during ram load
+are not validated. Especially offset in host_from_stream_offset() and
+also the length of the writes in the callers of said function.
+
+To fix this, we need to make sure that the [offset, offset + length]
+range fits into one of the allocated memory regions.
+
+Validating addr < len should be sufficient since data seems to always be
+managed in TARGET_PAGE_SIZE chunks.
+
+Fixes: CVE-2014-7840
+
+Note: follow-up patches add extra checks on each block->host access.
+
+Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
+Reviewed-by: Paolo Bonzini <pbonzini at redhat.com>
+Reviewed-by: Dr. David Alan Gilbert <dgilbert at redhat.com>
+Signed-off-by: Amit Shah <amit.shah at redhat.com>
+(cherry picked from commit 0be839a2701369f669532ea5884c15bead1c6e08)
+
+Conflicts:
+ arch_init.c
+---
+ arch_init.c | 7 ++++---
+ 1 file changed, 4 insertions(+), 3 deletions(-)
+
+diff --git a/arch_init.c b/arch_init.c
+index 23151b3..b6f7958 100644
+--- a/arch_init.c
++++ b/arch_init.c
+@@ -816,8 +816,8 @@ static inline void *host_from_stream_offset(QEMUFile *f,
+ uint8_t len;
+
+ if (flags & RAM_SAVE_FLAG_CONTINUE) {
+- if (!block) {
+- fprintf(stderr, "Ack, bad migration stream!\n");
++ if (!block || block->length <= offset) {
++ fprintf(stderr, "Ack, bad migration stream!");
+ return NULL;
+ }
+
+@@ -829,8 +829,9 @@ static inline void *host_from_stream_offset(QEMUFile *f,
+ id[len] = 0;
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+- if (!strncmp(id, block->idstr, sizeof(id)))
++ if (!strncmp(id, block->idstr, sizeof(id)) && block->length > offset) {
+ return memory_region_get_ram_ptr(block->mr) + offset;
++ }
+ }
+
+ fprintf(stderr, "Can't find block %s!\n", id);
diff --git a/qemu.spec b/qemu.spec
index abb9c3b..10dedc4 100644
--- a/qemu.spec
+++ b/qemu.spec
@@ -139,7 +139,7 @@
Summary: QEMU is a FAST! processor emulator
Name: qemu
Version: 1.6.2
-Release: 10%{?dist}
+Release: 11%{?dist}
Epoch: 2
License: GPLv2+ and LGPLv2+ and BSD
Group: Development/Tools
@@ -369,6 +369,12 @@ Patch0415: 0415-vmware-vga-add-vmsvga_verify_rect.patch
Patch0416: 0416-vmware-vga-use-vmsvga_verify_rect-in-vmsvga_update_r.patch
Patch0417: 0417-vmware-vga-use-vmsvga_verify_rect-in-vmsvga_copy_rec.patch
Patch0418: 0418-vmware-vga-use-vmsvga_verify_rect-in-vmsvga_fill_rec.patch
+# Fix SLES11 migration issue (bz #1109427)
+Patch0419: 0419-kvmclock-Ensure-time-in-migration-never-goes-backwar.patch
+Patch0420: 0420-kvmclock-Ensure-proper-env-tsc-value-for-kvmclock_cu.patch
+# CVE-2014-7840: insufficient parameter validation during ram load (bz
+# #1163080)
+Patch0421: 0421-migration-fix-parameter-validation-on-ram-load.patch
BuildRequires: SDL-devel
BuildRequires: zlib-devel
@@ -1070,6 +1076,12 @@ CAC emulation development files.
%patch0416 -p1
%patch0417 -p1
%patch0418 -p1
+# Fix SLES11 migration issue (bz #1109427)
+%patch0419 -p1
+%patch0420 -p1
+# CVE-2014-7840: insufficient parameter validation during ram load (bz
+# #1163080)
+%patch0421 -p1
%build
@@ -1777,6 +1789,11 @@ getent passwd qemu >/dev/null || \
%endif
%changelog
+* Sun Nov 30 2014 Cole Robinson <crobinso at redhat.com> - 2:1.6.2-11
+- Fix SLES11 migration issue (bz #1109427)
+- CVE-2014-7840: insufficient parameter validation during ram load (bz
+ #1163080)
+
* Wed Oct 29 2014 Cole Robinson <crobinso at redhat.com> - 2:1.6.2-10
- CVE-2014-7815 vnc: insufficient bits_per_pixel from the client sanitization
(bz #1157647, bz #1157641)
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