Commit Graph

51729 Commits

Author SHA1 Message Date
Peter Maydell
39ae2474e3 armv7m: Extract "exception taken" code into functions
Extract the code from the tail end of arm_v7m_do_interrupt() which
enters the exception handler into a pair of utility functions
v7m_exception_taken() and v7m_push_stack(), which correspond roughly
to the pseudocode PushStack() and ExceptionTaken().

This also requires us to move the arm_v7m_load_vector() utility
routine up so we can call it.

Handling illegal exception returns has some cases where we want to
take a UsageFault either on an existing stack frame or with a new
stack frame but with a specific LR value, so we want to be able to
call these without having to go via arm_v7m_cpu_do_interrupt().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00
Michael Davidsaver
14790f730a armv7m: VECTCLRACTIVE and VECTRESET are UNPREDICTABLE
The VECTCLRACTIVE and VECTRESET bits in the AIRCR are both
documented as UNPREDICTABLE if you write a 1 to them when
the processor is not halted in Debug state (ie stopped
and under the control of an external JTAG debugger).
Since we don't implement Debug state or emulated JTAG
these bits are always UNPREDICTABLE for us. Instead of
logging them as unimplemented we can simply log writes
as guest errors and ignore them.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: change extracted from another patch; commit message
 constructed from scratch]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00
Michael Davidsaver
a25dc805e2 armv7m: Simpler and faster exception start
All the places in armv7m_cpu_do_interrupt() which pend an
exception in the NVIC are doing so for synchronous
exceptions. We know that we will always take some
exception in this case, so we can just acknowledge it
immediately, rather than returning and then immediately
being called again because the NVIC has raised its outbound
IRQ line.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: tweaked commit message; added DEBUG to the set of
exceptions we handle immediately, since it is synchronous
when it results from the BKPT instruction]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00
Peter Maydell
a5d8235545 armv7m: Remove unused armv7m_nvic_acknowledge_irq() return value
Having armv7m_nvic_acknowledge_irq() return the new value of
env->v7m.exception and its one caller assign the return value
back to env->v7m.exception is pointless. Just make the return
type void instead.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:18 +00:00
Michael Davidsaver
a73c98e159 armv7m: Escalate exceptions to HardFault if necessary
The v7M exception architecture requires that if a synchronous
exception cannot be taken immediately (because it is disabled
or at too low a priority) then it should be escalated to
HardFault (and the HardFault exception is then taken).
Implement this escalation logic.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: extracted from another patch]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Michael Davidsaver
7c14b3ac07 arm: gic: Remove references to NVIC
Now that the NVIC is its own separate implementation, we can
clean up the GIC code by removing REV_NVIC and conditionals
which use it.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Peter Maydell
7ecdaa4a96 armv7m: Fix condition check for taking exceptions
The M profile condition for when we can take a pending exception or
interrupt is not the same as that for A/R profile.  The code
originally copied from the A/R profile version of the
cpu_exec_interrupt function only worked by chance for the
very simple case of exceptions being masked by PRIMASK.
Replace it with a call to a function in the NVIC code that
correctly compares the priority of the pending exception
against the current execution priority of the CPU.

[Michael Davidsaver's patchset had a patch to do something
similar but the implementation ended up being a rewrite.]

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Michael Davidsaver
da6d674e50 armv7m: Rewrite NVIC to not use any GIC code
Despite some superficial similarities of register layout, the
M-profile NVIC is really very different from the A-profile GIC.
Our current attempt to reuse the GIC code means that we have
significant bugs in our NVIC.

Implement the NVIC as an entirely separate device, to give
us somewhere we can get the behaviour correct.

This initial commit does not attempt to implement exception
priority escalation, since the GIC-based code didn't either.
It does fix a few bugs in passing:
 * ICSR.RETTOBASE polarity was wrong and didn't account for
   internal exceptions
 * ICSR.VECTPENDING was 16 too high if the pending exception
   was for an external interrupt
 * UsageFault, BusFault and MemFault were not disabled on reset
   as they are supposed to be

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
[PMM: reworked, various bugs and stylistic cleanups]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:17 +00:00
Peter Maydell
1004102a77 armv7m: Implement reading and writing of PRIGROUP
Add a state field for the v7M PRIGROUP register and implent
reading and writing it. The current NVIC doesn't honour
the values written, but the new version will.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:16 +00:00
Peter Maydell
f797c07507 armv7m: Rename nvic_state to NVICState
Rename the nvic_state struct to NVICState, to match
our naming conventions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2017-02-28 12:08:16 +00:00
Kurban Mallachiev
c98c9eba88 ARM i.MX timers: fix reset handling
The i.MX timer device can be reset by writing to the SWR bit
of the CR register. This has to behave differently from hard
(power-on) reset because it does not reset all of the bits
in the CR register.

We were incorrectly implementing soft reset and hard reset
the same way, and in addition had a logic error which meant
that we were clearing the bits that soft-reset is supposed
to preserve and not touching the bits that soft-reset clears.
This was not correct behaviour for either kind of reset.

Separate out the soft reset and hard reset code paths, and
correct the handling of reset of the CR register so that it
is correct in both cases.

Signed-off-by: Kurban Mallachiev <mallachiev@ispras.ru>
[PMM: rephrased commit message, spacing on operators;
 use bool rather than int for is_soft_reset]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:16 +00:00
Eric Auger
ccc11b0279 hw/arm/virt: Add a user option to disallow ITS instantiation
In 2.9 ITS will block save/restore and migration use cases. As such,
let's introduce a user option that allows to turn its instantiation
off, along with GICv3. With the "its" option turned false, migration
will be possible, obviously at the expense of MSI support (with GICv3).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-id: 1487681108-14452-1-git-send-email-eric.auger@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:16 +00:00
Peter Maydell
44d7ce0ef3 cputlb: Don't assume do_unassigned_access() never returns
In get_page_addr_code(), if the guest PC doesn't correspond to RAM
then we currently run the CPU's do_unassigned_access() hook if it has
one, and otherwise we give up and exit QEMU with a more-or-less
useful message.  This code assumes that the do_unassigned_access hook
will never return, because if it does then we'll plough on attempting
to use a non-RAM TLB entry to get a RAM address and will abort() in
qemu_ram_addr_from_host_nofail().  Unfortunately some CPU
implementations of this hook do return: Microblaze, SPARC and the ARM
v7M.

Change the code to call report_bad_exec() if the hook returns, as
well as if it didn't have one.  This means we can tidy it up to use
the cpu_unassigned_access() function which wraps the "get the CPU
class and call the hook if it has one" work, since we aren't trying
to distinguish "no hook" from "hook existed and returned" any more.

This brings the handling of this hook into line with the handling
used for data accesses, where "hook returned" is treated the
same as "no hook existed" and gets you the default behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-02-28 12:08:15 +00:00
Nick Reilly
a4f5c5b723 Add missing fp_access_check() to aarch64 crypto instructions
The aarch64 crypto instructions for AES and SHA are missing the
check for if the FPU is enabled.

Signed-off-by: Nick Reilly <nreilly@blackberry.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:15 +00:00
Igor Mammedov
dbb74759fa hw/arm/virt: fix cpu object reference leak
object_new(FOO) returns an object with ref_cnt == 1
and following
  object_property_set_bool(cpuobj, true, "realized", NULL)
set parent of cpuobj to '/machine/unattached' which makes
ref_cnt == 2.

Since machvirt_init() doesn't take ownership of cpuobj
returned by object_new() it should explicitly drop
reference to cpuobj when dangling pointer is about to
go out of scope like it's done pc_new_cpu() to avoid
object leak.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-id: 1487253461-269218-1-git-send-email-imammedo@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:15 +00:00
Prasad J Pandit
241999bf4c sd: sdhci: Remove block count enable check in single block transfers
In SDHCI protocol, the 'Block count enable' bit of the Transfer
Mode register is relevant only in multi block transfers. We need
not check it in single block transfers.

Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-5-ppandit@redhat.com
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:15 +00:00
Prasad J Pandit
45ba9f761b sd: sdhci: conditionally invoke multi block transfer
In sdhci_write invoke multi block transfer if it is enabled
in the transfer mode register 's->trnmod'.

Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-4-ppandit@redhat.com
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:14 +00:00
Prasad J Pandit
6e86d90352 sd: sdhci: check transfer mode register in multi block transfer
In the SDHCI protocol, the transfer mode register value
is used during multi block transfer to check if block count
register is enabled and should be updated. Transfer mode
register could be set such that, block count register would
not be updated, thus leading to an infinite loop. Add check
to avoid it.

Reported-by: Wjjzhang <wjjzhang@tencent.com>
Reported-by: Jiang Xin <jiangxin1@huawei.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 20170214185225.7994-3-ppandit@redhat.com
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:14 +00:00
Prasad J Pandit
8b20aefac4 sd: sdhci: mask transfer mode register value
In SDHCI protocol, the transfer mode register is defined
to be of 6 bits. Mask its value with '0x0037' so that an
invalid value could not be assigned.

Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 20170214185225.7994-2-ppandit@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:14 +00:00
Peter Maydell
373442ea3a bcm2835_rng: Use qcrypto_random_bytes() rather than rand()
Switch to using qcrypto_random_bytes() rather than rand() as
our source of randomness for the BCM2835 RNG.

If qcrypto_random_bytes() fails, we don't want to return the guest a
non-random value in case they're really using it for cryptographic
purposes, so the best we can do is a fatal error.  This shouldn't
happen unless something's broken, though.

In theory we could implement this device's full FIFO and interrupt
semantics and then just stop filling the FIFO.  That's a lot of work,
though, and doesn't really give a very nice diagnostic to the user
since the guest will just seem to hang.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
2017-02-28 12:08:14 +00:00
Marcin Chojnacki
54a5ba13a9 target-arm: Implement BCM2835 hardware RNG
Recent vanilla Raspberry Pi kernels started to make use of
the hardware random number generator in BCM2835 SoC. As a
result, those kernels wouldn't work anymore under QEMU
but rather just freeze during the boot process.

This patch implements a trivial BCM2835 compatible RNG,
and adds it as a peripheral to BCM2835 platform, which
allows to boot a vanilla Raspberry Pi kernel under Qemu.

Changes since v1:
 * Prevented guest from writing [31..20] bits in rng_status
 * Removed redundant minimum_version_id_old
 * Added field entries for the state
 * Changed realize function to reset

Signed-off-by: Marcin Chojnacki <marcinch7@gmail.com>
Message-id: 20170210210857.47893-1-marcinch7@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:08:13 +00:00
Peter Maydell
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Merge remote-tracking branch 'remotes/vivier2/tags/linux-user-for-upstream-pull-request' into staging

# gpg: Signature made Mon 27 Feb 2017 22:15:47 GMT
# gpg:                using RSA key 0xF30C38BD3F2FBE3C
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>"
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>"
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>"
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier2/tags/linux-user-for-upstream-pull-request:
  syscall: fixed mincore(2) not failing with ENOMEM
  linux-user: fix do_rt_sigreturn on m68k linux userspace emulation
  linux-user: correctly manage SR in ucontext
  linux-user: Add signal handling support for x86_64
  linux-user: Add sockopts for IPv6 ping and IPv6 traceroute
  linux-user: fix fork()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-28 12:03:36 +00:00
Cornelia Huck
e8ebf60f6d pc-bios/s390-ccw.img: rebuild image
Contains the following commits:
- pc-bios/s390-ccw: Use the ccw bios to start the network boot

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-28 12:04:48 +01:00
Farhan Ali
99b72e0fbb pc-bios/s390-ccw: Use the ccw bios to start the network boot
We want to use the ccw bios to start final network boot. To do
this we use ccw bios to detect if the boot device is a virtio
network device and retrieve the start address of the
network boot image.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-28 12:04:48 +01:00
Farhan Ali
f38b5b7fc4 s390x/ipl: Load network boot image
Load the network boot image into guest RAM when the boot
device selected is a network device. Use some of the reserved
space in IplBlockCcw to store the start address of the netboot
image.

A user could also use 'chreipl'(diag 308/5) to change the boot device.
So every time we update the IPLB, we need to verify if the selected
boot device is a network device so we can appropriately load the
network boot image.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-28 12:04:48 +01:00
Farhan Ali
5f31ade055 s390x/ipl: Extend S390IPLState to support network boot
Add new field to S390IPLState to store the name of the network boot
loader.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
2017-02-28 12:04:48 +01:00
Farhan Ali
34f1b23f8a elf-loader: Allow late loading of elf
The current QEMU ROM infrastructure rejects late loading of ROMs.
And ELFs are currently loaded as ROM, this prevents delayed loading
of ELFs. So when loading ELF, allow the user to specify if ELF should
be loaded as ROM or not.

If an ELF is not loaded as ROM, then they are not restored on a
guest reboot/reset and so its upto the user to handle the reloading.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-28 12:04:48 +01:00
Greg Kurz
c23d5f1d5b 9pfs: local: drop unused code
Now that the all callbacks have been converted to use "at" syscalls, we
can drop this code.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a565fea565 9pfs: local: open2: don't follow symlinks
The local_open2() callback is vulnerable to symlink attacks because it
calls:

(1) open() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_open2() to rely on opendir_nofollow() and
mkdirat() to fix (1), as well as local_set_xattrat(),
local_set_mapped_file_attrat() and local_set_cred_passthrough() to
fix (2), (3) and (4) respectively. Since local_open2() already opens
a descriptor to the target file, local_set_cred_passthrough() is
modified to reuse it instead of opening a new one.

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to openat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
3f3a16990b 9pfs: local: mkdir: don't follow symlinks
The local_mkdir() callback is vulnerable to symlink attacks because it
calls:

(1) mkdir() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_mkdir() to rely on opendir_nofollow() and
mkdirat() to fix (1), as well as local_set_xattrat(),
local_set_mapped_file_attrat() and local_set_cred_passthrough() to
fix (2), (3) and (4) respectively.

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to mkdirat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d815e72190 9pfs: local: mknod: don't follow symlinks
The local_mknod() callback is vulnerable to symlink attacks because it
calls:

(1) mknod() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_mknod() to rely on opendir_nofollow() and
mknodat() to fix (1), as well as local_set_xattrat() and
local_set_mapped_file_attrat() to fix (2) and (3) respectively.

A new local_set_cred_passthrough() helper based on fchownat() and
fchmodat_nofollow() is introduced as a replacement to
local_post_create_passthrough() to fix (4).

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to mknodat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
38771613ea 9pfs: local: symlink: don't follow symlinks
The local_symlink() callback is vulnerable to symlink attacks because it
calls:

(1) symlink() which follows symbolic links for all path elements but the
    rightmost one
(2) open(O_NOFOLLOW) which follows symbolic links for all path elements but
    the rightmost one
(3) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(4) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

This patch converts local_symlink() to rely on opendir_nofollow() and
symlinkat() to fix (1), openat(O_NOFOLLOW) to fix (2), as well as
local_set_xattrat() and local_set_mapped_file_attrat() to fix (3) and
(4) respectively.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d369f20763 9pfs: local: chown: don't follow symlinks
The local_chown() callback is vulnerable to symlink attacks because it
calls:

(1) lchown() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

This patch converts local_chown() to rely on open_nofollow() and
fchownat() to fix (1), as well as local_set_xattrat() and
local_set_mapped_file_attrat() to fix (2) and (3) respectively.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
e3187a45dd 9pfs: local: chmod: don't follow symlinks
The local_chmod() callback is vulnerable to symlink attacks because it
calls:

(1) chmod() which follows symbolic links for all path elements
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

We would need fchmodat() to implement AT_SYMLINK_NOFOLLOW to fix (1). This
isn't the case on linux unfortunately: the kernel doesn't even have a flags
argument to the syscall :-\ It is impossible to fix it in userspace in
a race-free manner. This patch hence converts local_chmod() to rely on
open_nofollow() and fchmod(). This fixes the vulnerability but introduces
a limitation: the target file must readable and/or writable for the call
to openat() to succeed.

It introduces a local_set_xattrat() replacement to local_set_xattr()
based on fsetxattrat() to fix (2), and a local_set_mapped_file_attrat()
replacement to local_set_mapped_file_attr() based on local_fopenat()
and mkdirat() to fix (3). No effort is made to factor out code because
both local_set_xattr() and local_set_mapped_file_attr() will be dropped
when all users have been converted to use the "at" versions.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
ad0b46e6ac 9pfs: local: link: don't follow symlinks
The local_link() callback is vulnerable to symlink attacks because it calls:

(1) link() which follows symbolic links for all path elements but the
    rightmost one
(2) local_create_mapped_attr_dir()->mkdir() which follows symbolic links
    for all path elements but the rightmost one

This patch converts local_link() to rely on opendir_nofollow() and linkat()
to fix (1), mkdirat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
6dd4b1f1d0 9pfs: local: improve error handling in link op
When using the mapped-file security model, we also have to create a link
for the metadata file if it exists. In case of failure, we should rollback.

That's what this patch does.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d2767edec5 9pfs: local: rename: use renameat
The local_rename() callback is vulnerable to symlink attacks because it
uses rename() which follows symbolic links in all path elements but the
rightmost one.

This patch simply transforms local_rename() into a wrapper around
local_renameat() which is symlink-attack safe.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
99f2cf4b2d 9pfs: local: renameat: don't follow symlinks
The local_renameat() callback is currently a wrapper around local_rename()
which is vulnerable to symlink attacks.

This patch rewrites local_renameat() to have its own implementation, based
on local_opendir_nofollow() and renameat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
f9aef99b3e 9pfs: local: lstat: don't follow symlinks
The local_lstat() callback is vulnerable to symlink attacks because it
calls:

(1) lstat() which follows symbolic links in all path elements but the
    rightmost one
(2) getxattr() which follows symbolic links in all path elements
(3) local_mapped_file_attr()->local_fopen()->openat(O_NOFOLLOW) which
    follows symbolic links in all path elements but the rightmost
    one

This patch converts local_lstat() to rely on opendir_nofollow() and
fstatat(AT_SYMLINK_NOFOLLOW) to fix (1), fgetxattrat_nofollow() to
fix (2).

A new local_fopenat() helper is introduced as a replacement to
local_fopen() to fix (3). No effort is made to factor out code
because local_fopen() will be dropped when all users have been
converted to call local_fopenat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
bec1e9546e 9pfs: local: readlink: don't follow symlinks
The local_readlink() callback is vulnerable to symlink attacks because it
calls:

(1) open(O_NOFOLLOW) which follows symbolic links for all path elements but
    the rightmost one
(2) readlink() which follows symbolic links for all path elements but the
    rightmost one

This patch converts local_readlink() to rely on open_nofollow() to fix (1)
and opendir_nofollow(), readlinkat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
ac125d993b 9pfs: local: truncate: don't follow symlinks
The local_truncate() callback is vulnerable to symlink attacks because
it calls truncate() which follows symbolic links in all path elements.

This patch converts local_truncate() to rely on open_nofollow() and
ftruncate() instead.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
31e51d1c15 9pfs: local: statfs: don't follow symlinks
The local_statfs() callback is vulnerable to symlink attacks because it
calls statfs() which follows symbolic links in all path elements.

This patch converts local_statfs() to rely on open_nofollow() and fstatfs()
instead.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a33eda0dd9 9pfs: local: utimensat: don't follow symlinks
The local_utimensat() callback is vulnerable to symlink attacks because it
calls qemu_utimens()->utimensat(AT_SYMLINK_NOFOLLOW) which follows symbolic
links in all path elements but the rightmost one or qemu_utimens()->utimes()
which follows symbolic links for all path elements.

This patch converts local_utimensat() to rely on opendir_nofollow() and
utimensat(AT_SYMLINK_NOFOLLOW) directly instead of using qemu_utimens().
It is hence assumed that the OS supports utimensat(), i.e. has glibc 2.6
or higher and linux 2.6.22 or higher, which seems reasonable nowadays.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a0e640a872 9pfs: local: remove: don't follow symlinks
The local_remove() callback is vulnerable to symlink attacks because it
calls:

(1) lstat() which follows symbolic links in all path elements but the
    rightmost one
(2) remove() which follows symbolic links in all path elements but the
    rightmost one

This patch converts local_remove() to rely on opendir_nofollow(),
fstatat(AT_SYMLINK_NOFOLLOW) to fix (1) and unlinkat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
df4938a665 9pfs: local: unlinkat: don't follow symlinks
The local_unlinkat() callback is vulnerable to symlink attacks because it
calls remove() which follows symbolic links in all path elements but the
rightmost one.

This patch converts local_unlinkat() to rely on opendir_nofollow() and
unlinkat() instead.

Most of the code is moved to a separate local_unlinkat_common() helper
which will be reused in a subsequent patch to fix the same issue in
local_remove().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
72f0d0bf51 9pfs: local: lremovexattr: don't follow symlinks
The local_lremovexattr() callback is vulnerable to symlink attacks because
it calls lremovexattr() which follows symbolic links in all path elements
but the rightmost one.

This patch introduces a helper to emulate the non-existing fremovexattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lremovexattr().

local_lremovexattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
3e36aba757 9pfs: local: lsetxattr: don't follow symlinks
The local_lsetxattr() callback is vulnerable to symlink attacks because
it calls lsetxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing fsetxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lsetxattr().

local_lsetxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
5507904e36 9pfs: local: llistxattr: don't follow symlinks
The local_llistxattr() callback is vulnerable to symlink attacks because
it calls llistxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing flistxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to llistxattr().

local_llistxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
56ad3e54da 9pfs: local: lgetxattr: don't follow symlinks
The local_lgetxattr() callback is vulnerable to symlink attacks because
it calls lgetxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing fgetxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lgetxattr().

local_lgetxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
996a0d76d7 9pfs: local: open/opendir: don't follow symlinks
The local_open() and local_opendir() callbacks are vulnerable to symlink
attacks because they call:

(1) open(O_NOFOLLOW) which follows symbolic links in all path elements but
    the rightmost one
(2) opendir() which follows symbolic links in all path elements

This patch converts both callbacks to use new helpers based on
openat_nofollow() to only open files and directories if they are
below the virtfs shared folder

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00