gnu: qemu: Add fixes for CVE-2015-5154 and CVE-2015-5158.

* gnu/packages/patches/qemu-CVE-2015-5154-pt1.patch,
  gnu/packages/patches/qemu-CVE-2015-5154-pt2.patch,
  gnu/packages/patches/qemu-CVE-2015-5154-pt3.patch,
  gnu/packages/patches/qemu-CVE-2015-5158.patch: New files.
* gnu-system.am (dist_patch_DATA): Add them.
* gnu/packages/qemu.scm (qemu-headless)[source]: Add patches.

4 files changed, 220 insertions, 0 deletions

diff --git a/gnu/packages/patches/qemu-CVE-2015-5154-pt1.patch b/gnu/packages/patches/qemu-CVE-2015-5154-pt1.patch
new file mode 100644
index 0000000000..8a41848ddf
--- /dev/null
+++ b/gnu/packages/patches/qemu-CVE-2015-5154-pt1.patch
@@ -0,0 +1,76 @@
+From a9de14175548c04e0f8be7fae219246509ba46a9 Mon Sep 17 00:00:00 2001
+From: Kevin Wolf <kwolf@redhat.com>
+Date: Wed, 3 Jun 2015 14:13:31 +0200
+Subject: [PATCH 1/3] ide: Check array bounds before writing to io_buffer
+ (CVE-2015-5154)
+
+If the end_transfer_func of a command is called because enough data has
+been read or written for the current PIO transfer, and it fails to
+correctly call the command completion functions, the DRQ bit in the
+status register and s->end_transfer_func may remain set. This allows the
+guest to access further bytes in s->io_buffer beyond s->data_end, and
+eventually overflowing the io_buffer.
+
+One case where this currently happens is emulation of the ATAPI command
+START STOP UNIT.
+
+This patch fixes the problem by adding explicit array bounds checks
+before accessing the buffer instead of relying on end_transfer_func to
+function correctly.
+
+Cc: qemu-stable@nongnu.org
+Signed-off-by: Kevin Wolf <kwolf@redhat.com>
+---
+ hw/ide/core.c | 16 ++++++++++++++++
+ 1 file changed, 16 insertions(+)
+
+diff --git a/hw/ide/core.c b/hw/ide/core.c
+index 122e955..44fcc23 100644
+--- a/hw/ide/core.c
++++ b/hw/ide/core.c
+@@ -2021,6 +2021,10 @@ void ide_data_writew(void *opaque, uint32_t addr, uint32_t val)
+     }
+ 
+     p = s->data_ptr;
++    if (p + 2 > s->data_end) {
++        return;
++    }
++
+     *(uint16_t *)p = le16_to_cpu(val);
+     p += 2;
+     s->data_ptr = p;
+@@ -2042,6 +2046,10 @@ uint32_t ide_data_readw(void *opaque, uint32_t addr)
+     }
+ 
+     p = s->data_ptr;
++    if (p + 2 > s->data_end) {
++        return 0;
++    }
++
+     ret = cpu_to_le16(*(uint16_t *)p);
+     p += 2;
+     s->data_ptr = p;
+@@ -2063,6 +2071,10 @@ void ide_data_writel(void *opaque, uint32_t addr, uint32_t val)
+     }
+ 
+     p = s->data_ptr;
++    if (p + 4 > s->data_end) {
++        return;
++    }
++
+     *(uint32_t *)p = le32_to_cpu(val);
+     p += 4;
+     s->data_ptr = p;
+@@ -2084,6 +2096,10 @@ uint32_t ide_data_readl(void *opaque, uint32_t addr)
+     }
+ 
+     p = s->data_ptr;
++    if (p + 4 > s->data_end) {
++        return 0;
++    }
++
+     ret = cpu_to_le32(*(uint32_t *)p);
+     p += 4;
+     s->data_ptr = p;
+-- 
+1.8.3.1
diff --git a/gnu/packages/patches/qemu-CVE-2015-5154-pt2.patch b/gnu/packages/patches/qemu-CVE-2015-5154-pt2.patch
new file mode 100644
index 0000000000..f860cfa3db
--- /dev/null
+++ b/gnu/packages/patches/qemu-CVE-2015-5154-pt2.patch
@@ -0,0 +1,28 @@
+From aa851d30acfbb9580098ac1dc82885530cb8b3c1 Mon Sep 17 00:00:00 2001
+From: Kevin Wolf <kwolf@redhat.com>
+Date: Wed, 3 Jun 2015 14:17:46 +0200
+Subject: [PATCH 2/3] ide/atapi: Fix START STOP UNIT command completion
+
+The command must be completed on all code paths. START STOP UNIT with
+pwrcnd set should succeed without doing anything.
+
+Signed-off-by: Kevin Wolf <kwolf@redhat.com>
+---
+ hw/ide/atapi.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/hw/ide/atapi.c b/hw/ide/atapi.c
+index 950e311..79dd167 100644
+--- a/hw/ide/atapi.c
++++ b/hw/ide/atapi.c
+@@ -983,6 +983,7 @@ static void cmd_start_stop_unit(IDEState *s, uint8_t* buf)
+
+     if (pwrcnd) {
+         /* eject/load only happens for power condition == 0 */
++        ide_atapi_cmd_ok(s);
+         return;
+     }
+
+--
+1.8.3.1
+
diff --git a/gnu/packages/patches/qemu-CVE-2015-5154-pt3.patch b/gnu/packages/patches/qemu-CVE-2015-5154-pt3.patch
new file mode 100644
index 0000000000..3ade9b1600
--- /dev/null
+++ b/gnu/packages/patches/qemu-CVE-2015-5154-pt3.patch
@@ -0,0 +1,71 @@
+From 1d3c2268f8708126a34064c2e0c1000b40e6f3e5 Mon Sep 17 00:00:00 2001
+From: Kevin Wolf <kwolf@redhat.com>
+Date: Wed, 3 Jun 2015 14:41:27 +0200
+Subject: [PATCH 3/3] ide: Clear DRQ after handling all expected accesses
+
+This is additional hardening against an end_transfer_func that fails to
+clear the DRQ status bit. The bit must be unset as soon as the PIO
+transfer has completed, so it's better to do this in a central place
+instead of duplicating the code in all commands (and forgetting it in
+some).
+
+Signed-off-by: Kevin Wolf <kwolf@redhat.com>
+---
+ hw/ide/core.c | 16 ++++++++++++----
+ 1 file changed, 12 insertions(+), 4 deletions(-)
+
+diff --git a/hw/ide/core.c b/hw/ide/core.c
+index 44fcc23..50449ca 100644
+--- a/hw/ide/core.c
++++ b/hw/ide/core.c
+@@ -2028,8 +2028,10 @@ void ide_data_writew(void *opaque, uint32_t addr, uint32_t val)
+     *(uint16_t *)p = le16_to_cpu(val);
+     p += 2;
+     s->data_ptr = p;
+-    if (p >= s->data_end)
++    if (p >= s->data_end) {
++        s->status &= ~DRQ_STAT;
+         s->end_transfer_func(s);
++    }
+ }
+
+ uint32_t ide_data_readw(void *opaque, uint32_t addr)
+@@ -2053,8 +2055,10 @@ uint32_t ide_data_readw(void *opaque, uint32_t addr)
+     ret = cpu_to_le16(*(uint16_t *)p);
+     p += 2;
+     s->data_ptr = p;
+-    if (p >= s->data_end)
++    if (p >= s->data_end) {
++        s->status &= ~DRQ_STAT;
+         s->end_transfer_func(s);
++    }
+     return ret;
+ }
+
+@@ -2078,8 +2082,10 @@ void ide_data_writel(void *opaque, uint32_t addr, uint32_t val)
+     *(uint32_t *)p = le32_to_cpu(val);
+     p += 4;
+     s->data_ptr = p;
+-    if (p >= s->data_end)
++    if (p >= s->data_end) {
++        s->status &= ~DRQ_STAT;
+         s->end_transfer_func(s);
++    }
+ }
+
+ uint32_t ide_data_readl(void *opaque, uint32_t addr)
+@@ -2103,8 +2109,10 @@ uint32_t ide_data_readl(void *opaque, uint32_t addr)
+     ret = cpu_to_le32(*(uint32_t *)p);
+     p += 4;
+     s->data_ptr = p;
+-    if (p >= s->data_end)
++    if (p >= s->data_end) {
++        s->status &= ~DRQ_STAT;
+         s->end_transfer_func(s);
++    }
+     return ret;
+ }
+
+--
+1.8.3.1
+
diff --git a/gnu/packages/patches/qemu-CVE-2015-5158.patch b/gnu/packages/patches/qemu-CVE-2015-5158.patch
new file mode 100644
index 0000000000..bedbfc8fa4
--- /dev/null
+++ b/gnu/packages/patches/qemu-CVE-2015-5158.patch
@@ -0,0 +1,45 @@
+c170aad8b057223b1139d72e5ce7acceafab4fa9
+Author: Paolo Bonzini <pbonzini@redhat.com>
+Date:   Tue Jul 21 08:59:39 2015 +0200
+
+    scsi: fix buffer overflow in scsi_req_parse_cdb (CVE-2015-5158)
+    
+    This is a guest-triggerable buffer overflow present in QEMU 2.2.0
+    and newer.  scsi_cdb_length returns -1 as an error value, but the
+    caller does not check it.
+    
+    Luckily, the massive overflow means that QEMU will just SIGSEGV,
+    making the impact much smaller.
+    
+    Reported-by: Zhu Donghai (朱东海) <donghai.zdh@alibaba-inc.com>
+    Fixes: 1894df02811f6b79ea3ffbf1084599d96f316173
+    Reviewed-by: Fam Zheng <famz@redhat.com>
+    Cc: qemu-stable@nongnu.org
+    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
+
+1 file changed, 6 insertions(+), 1 deletion(-)
+ hw/scsi/scsi-bus.c | 7 ++++++-
+
+	Modified   hw/scsi/scsi-bus.c
+diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
+index f50b2f0..f0ae462 100644
+--- a/hw/scsi/scsi-bus.c
++++ b/hw/scsi/scsi-bus.c
+@@ -1239,10 +1239,15 @@ int scsi_cdb_length(uint8_t *buf) {
+ int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf)
+ {
+     int rc;
++    int len;
+ 
+     cmd->lba = -1;
+-    cmd->len = scsi_cdb_length(buf);
++    len = scsi_cdb_length(buf);
++    if (len < 0) {
++        return -1;
++    }
+ 
++    cmd->len = len;
+     switch (dev->type) {
+     case TYPE_TAPE:
+         rc = scsi_req_stream_xfer(cmd, dev, buf);
+