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584 commits

Author SHA1 Message Date
Peter Maydell 415d847110 linux-user: Use g_try_malloc() in do_msgrcv()
In do_msgrcv() we want to allocate a message buffer, whose size
is passed to us by the guest. That means we could legitimately
fail, so use g_try_malloc() and handle the error case, in the same
way that do_msgsnd() does.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:39 +03:00
Peter Maydell 99874f6552 linux-user: Handle msgrcv error case correctly
The msgrcv ABI is a bit odd -- the msgsz argument is a size_t, which is
unsigned, but it must fail EINVAL if the value is negative when cast
to a long. We were incorrectly passing the value through an
"unsigned int", which meant that if the guest was 32-bit longs and
the host was 64-bit longs an input of 0xffffffff (which should trigger
EINVAL) would simply be passed to the host msgrcv() as 0xffffffff,
where it does not cause the host kernel to reject it.
Follow the same approach as do_msgsnd() in using a ssize_t and
doing the check for negative values by hand, so we correctly fail
in this corner case.

This fixes the msgrcv03 Linux Test Project test case, which otherwise
hangs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:39 +03:00
Peter Maydell c7e35da348 linux-user: Handle negative values in timespec conversion
In a struct timespec, both fields are signed longs. Converting
them from guest to host with code like
    host_ts->tv_sec = tswapal(target_ts->tv_sec);
mishandles negative values if the guest has 32-bit longs and
the host has 64-bit longs because tswapal()'s return type is
abi_ulong: the assignment will zero-extend into the host long
type rather than sign-extending it.

Make the conversion routines use __get_user() and __set_user()
instead: this automatically picks up the signedness of the
field type and does the correct kind of sign or zero extension.
It also handles the possibility that the target struct is not
sufficiently aligned for the host's requirements.

In particular, this fixes a hang when running the Linux Test Project
mq_timedsend01 and mq_timedreceive01 tests: one of the test cases
sets the timeout to -1 and expects an EINVAL failure, but we were
setting a very long timeout instead.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:39 +03:00
Peter Maydell d509eeb13c linux-user: Use safe_syscall for futex syscall
Use the safe_syscall wrapper for the futex syscall.

In particular, this fixes hangs when using programs that link
against the Boehm garbage collector, including the Mono runtime.

(We don't change the sys_futex() call in the implementation of
the exit syscall, because as the FIXME comment there notes
that should be handled by disabling signals, since we can't
easily back out if the futex were to return ERESTARTSYS.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:39 +03:00
Peter Maydell 6df9d38d33 linux-user: Use safe_syscall for pselect, select syscalls
Use the safe_syscall wrapper for the pselect and select syscalls.
Since not every architecture has the select syscall, we now
have to implement select in terms of pselect, which means doing
timeval<->timespec conversion.

(Five years on from the initial patch that added pselect support
to QEMU and a decade after pselect6 went into the kernel, it seems
safe to not try to support hosts with header files which don't
define __NR_pselect6.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:38 +03:00
Timothy E Baldwin ffdcbe223d linux-user: Use safe_syscall for execve syscall
Wrap execve() in the safe-syscall handling. Although execve() is not
an interruptible syscall, it is a special case: if we allow a signal
to happen before we make the host$ syscall then we will 'lose' it,
because at the point of execve the process leaves QEMU's control.  So
we use the safe syscall wrapper to ensure that we either take the
signal as a guest signal, or else it does not happen before the
execve completes and makes it the other program's problem.

The practical upshot is that without this SIGTERM could fail to
terminate the process.

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-25-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: expanded commit message to explain in more detail why this is
 needed, and add comment about it too]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:38 +03:00
Timothy E Baldwin 4af80a3783 linux-user: Use safe_syscall for wait system calls
Use safe_syscall for waitpid, waitid and wait4 syscalls. Note that this
change allows us to implement support for waitid's fifth (rusage) argument
in future; for the moment we ignore it as we have done up til now.

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-18-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Adjust to new safe_syscall convention. Add fifth waitid syscall argument
 (which isn't present in the libc interface but is in the syscall ABI)]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:38 +03:00
Timothy E Baldwin c10a07387b linux-user: Use safe_syscall for open and openat system calls
Restart open() and openat() if signals occur before,
or during with SA_RESTART.

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-17-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Adjusted to follow new -1-and-set-errno safe_syscall convention]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:38 +03:00
Timothy E Baldwin 50afd02b84 linux-user: Use safe_syscall for read and write system calls
Restart read() and write() if signals occur before, or during with SA_RESTART

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-15-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Update to new safe_syscall() convention of setting errno]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:50:38 +03:00
Timothy E Baldwin 4d330cee37 linux-user: Provide safe_syscall for fixing races between signals and syscalls
If a signal is delivered immediately before a blocking system call the
handler will only be called after the system call returns, which may be a
long time later or never.

This is fixed by using a function (safe_syscall) that checks if a guest
signal is pending prior to making a system call, and if so does not call the
system call and returns -TARGET_ERESTARTSYS. If a signal is received between
the check and the system call host_signal_handler() rewinds execution to
before the check. This rewinding has the effect of closing the race window
so that safe_syscall will reliably either (a) go into the host syscall
with no unprocessed guest signals pending or or (b) return
-TARGET_ERESTARTSYS so that the caller can deal with the signals.
Implementing this requires a per-host-architecture assembly language
fragment.

This will also resolve the mishandling of the SA_RESTART flag where
we would restart a host system call and not call the guest signal handler
until the syscall finally completed -- syscall restarting now always
happens at the guest syscall level so the guest signal handler will run.
(The host syscall will never be restarted because if the host kernel
rewinds the PC to point at the syscall insn for a restart then our
host_signal_handler() will see this and arrange the guest PC rewind.)

This commit contains the infrastructure for implementing safe_syscall
and the assembly language fragment for x86-64, but does not change any
syscalls to use it.

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-14-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM:
 * Avoid having an architecture if-ladder in configure by putting
   linux-user/host/$(ARCH) on the include path and including
   safe-syscall.inc.S from it
 * Avoid ifdef ladder in signal.c by creating new hostdep.h to hold
   host-architecture-specific things
 * Added copyright/license header to safe-syscall.inc.S
 * Rewrote commit message
 * Added comments to safe-syscall.inc.S
 * Changed calling convention of safe_syscall() to match syscall()
   (returns -1 and host error in errno on failure)
 * Added a long comment in qemu.h about how to use safe_syscall()
   to implement guest syscalls.
]
RV: squashed Peters "fixup! linux-user: compile on non-x86-64 hosts"
patch
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-27 14:49:51 +03:00
Timothy E Baldwin 71a8f7fece linux-user: Add debug code to exercise restarting system calls
If DEBUG_ERESTARTSYS is set restart all system calls once. This
is pure debug code for exercising the syscall restart code paths
in the per-architecture cpu main loops.

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-10-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Add comment and a commented-out #define next to the commented-out
 generic DEBUG #define; remove the check on TARGET_USE_ERESTARTSYS;
 tweak comment message]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:49:51 +03:00
Timothy E Baldwin 0284b03ba3 linux-user: Support for restarting system calls for x86 targets
Update the x86 main loop and sigreturn code:
 * on TARGET_ERESTARTSYS, wind guest PC backwards to repeat syscall insn
 * set all guest CPU state within signal.c code rather than passing it
   back out as the "return code" from do_sigreturn()
 * handle TARGET_QEMU_ESIGRETURN in the main loop as the indication
   that the main loop should not touch EAX

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-5-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: Commit message tweaks; drop TARGET_USE_ERESTARTSYS define]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-05-27 14:49:49 +03:00
Peter Maydell a3ca7bb259 linux-user: Consistently return host errnos from do_openat()
The function do_openat() is not consistent about whether it is
returning a host errno or a guest errno in case of failure.
Standardise on returning -1 with errno set (ie caller has
to call get_errno()).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reported-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
2016-05-27 14:49:48 +03:00
Timothy E Baldwin 2466119c95 linux-user: Check array bounds in errno conversion
Check array bounds in host_to_target_errno() and target_to_host_errno().

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-2-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Add a lower-bound check, use braces on if(), tweak commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
2016-05-27 14:49:48 +03:00
Veronia Bahaa f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Laurent Vivier f894efd199 linux-user: add getrandom() syscall
getrandom() has been introduced in kernel 3.17 and is now used during
the boot sequence of Debian unstable (stretch/sid).

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-02-24 15:22:15 +02:00
Riku Voipio 13756fb008 linux-user: remove unavailable syscalls from aarch64
QEMU lists deprecated system call numbers in for Aarch64. These
are never enabled for Linux kernel, so don't define them in Qemu
either. Remove the ifdef around host_to_target_stat64 since
all architectures need it now.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-02-23 21:25:10 +02:00
Peter Maydell b6e17875f2 linux-user: Don't assert if guest tries shmdt(0)
Our implementation of shmat() and shmdt() for linux-user was
using "zero guest address" as its marker for "entry in the
shm_regions[] array is not in use". This meant that if the
guest did a shmdt(0) we would match on an unused array entry
and call page_set_flags() with both start and end addresses zero,
which causes an assertion failure.

Use an explicit in_use flag to manage the shm_regions[] array,
so that we avoid this problem.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reported-by: Pavel Shamis <pasharesearch@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-02-23 21:25:09 +02:00
Laurent Vivier 5089c7ce82 linux-user: fix realloc size of target_fd_trans.
target_fd_trans is an array of "TargetFdTrans *": compute size
accordingly. Use g_renew() as proposed by Paolo.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-02-23 21:25:09 +02:00
Peter Maydell d39594e9d9 linux-user: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-10-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:22 +00:00
John Paul Adrian Glaubitz 5a53dc5042 linux-user: Add SOCKOP_sendmmsg and SOCKOP_recvmmsg socket call, wire them up.
Adds the definitions for the socket calls SOCKOP_sendmmsg
and SOCKOP_recvmmsg and wires them up with the rest of the code.
The necessary function do_sendrecvmmsg() is already present in
linux-user/syscall.c. After adding these two definitions and wiring
them up, I no longer receive an error message about the
unimplemented socket calls when running "apt-get update" on Debian
unstable running on qemu with glibc_2.21 on m68k.

Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-11 14:54:03 +02:00
Chen Gang fad6c58a3d linux-user/syscall.c: Use SOL_SOCKET instead of level for setsockopt()
In this case, level is TARGET_SOL_SOCKET, but we need SOL_SOCKET for
setsockopt().

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-11 13:45:23 +02:00
Michael Tokarev c0d3573632 linux-user: enable sigaltstack for all architectures
There is no reason to limit sigaltstack syscall to just a few
architectures and pretend it is not implemented for others.

If some architecture is not ready for this, that architecture
should be fixed instead.

This fixes LP#1516408.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:36:21 +02:00
Laurent Vivier 861d72cd28 linux-user: check fd is >= 0 in fd_trans_host_to_target_data/fd_trans_host_to_target_addr
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:20:35 +02:00
Laurent Vivier 0cf227229b linux-user: manage bind with a socket of SOCK_PACKET type.
This is obsolete, but if we want to use dhcp with an old distro (like debian
etch), we need it. Some users (like dhclient) use SOCK_PACKET with AF_PACKET
and the kernel allows that.

packet(7)

  In Linux 2.0, the only way to  get  a  packet  socket  was  by calling
  socket(AF_INET,  SOCK_PACKET,  protocol).   This is still supported but
  strongly deprecated.  The main difference between the  two methods  is
  that  SOCK_PACKET uses the old struct sockaddr_pkt to specify an inter‐
  face, which doesn't provide physical layer independence.

     struct sockaddr_pkt {
         unsigned short spkt_family;
         unsigned char  spkt_device[14];
         unsigned short spkt_protocol;
     };

  spkt_family contains the device type, spkt_protocol is the  IEEE 802.3
  protocol  type  as  defined  in <sys/if_ether.h> and spkt_device is the
  device name as a null-terminated string, for example, eth0.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:20:15 +02:00
Laurent Vivier 7b36f78274 linux-user: add a function hook to translate sockaddr
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:20:08 +02:00
Laurent Vivier 5d4d366585 linux-user: rename TargetFdFunc to TargetFdDataFunc, and structure fields accordingly
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:19:57 +02:00
Laurent Vivier ff626f2d9e linux-user: SOCK_PACKET uses network endian to encode protocol in socket()
in PACKET(7) :

  packet_socket = socket(AF_PACKET, int socket_type, int protocol);
[...]
                                   protocol is the  IEEE  802.3 protocol
  number in network order.  See the <linux/if_ether.h> include file for a
  list of allowed protocols.  When protocol is  set  to htons(ETH_P_ALL)
  then all protocols are received.  All incoming packets of that protocol
  type will be passed to the packet socket before they are passed to the
  protocols implemented in the kernel.
[...]
Compatibility

  In Linux 2.0, the only way to  get  a  packet  socket  was  by  calling
  socket(AF_INET,  SOCK_PACKET,  protocol).

We need to tswap16() the protocol because on big-endian, the ABI is
waiting for, for instance for ETH_P_ALL, 0x0003 (big endian ==
network order), whereas on little-endian it is waiting for 0x0300.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 15:18:47 +02:00
Harmandeep Kaur 0e173b24b5 linux-user/syscall.c: malloc()/calloc() to g_malloc()/g_try_malloc()/g_new0()
Convert malloc()/ calloc() calls to g_malloc()/ g_try_malloc()/ g_new0()

All heap memory allocation should go through glib so that we can take
advantage of a single memory allocator and its debugging/tracing features.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Harmandeep Kaur <write.harmandeep@gmail.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 11:36:13 +02:00
Laurent Vivier 3e24bb3f12 linux-user: in poll(), if nfds is 0, pfd can be NULL
This problem appears with yum in Fedora 20 / PPC64 container.

test case:

    #include <stdio.h>
    #include <poll.h>

    int main(void)
    {
        int ret;

        ret = poll(NULL, 0, 1000);
        printf("%d\n", ret);
    }

target test environment: Fedora 20 / PPC64
host test environment: Ubuntu 14.0.2 / x86_64

original test result: -1

    13451 poll(0,0,1000,274886297496,268566664,268566648) = -1 errno=14 (Bad address)

patched test result: 0

    13536 poll(0,0,1000,274886297496,268566664,268566648) = 0

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 11:36:13 +02:00
Laurent Vivier e36800c91a linux-user: add signalfd/signalfd4 syscalls
This patch introduces a system very similar to the one used in the kernel
to attach specific functions to a given file descriptor.

In this case, we attach a specific "host_to_target()" translator to the fd
returned by signalfd() to be able to byte-swap the signalfd_siginfo
structure provided by read().

This patch allows to execute the example program given by
man signalfd(2):

 #include <sys/signalfd.h>
 #include <signal.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>

 #define handle_error(msg) \
     do { perror(msg); exit(EXIT_FAILURE); } while (0)

 int
 main(int argc, char *argv[])
 {
     sigset_t mask;
     int sfd;
     struct signalfd_siginfo fdsi;
     ssize_t s;

     sigemptyset(&mask);
     sigaddset(&mask, SIGINT);
     sigaddset(&mask, SIGQUIT);

     /* Block signals so that they aren't handled
        according to their default dispositions */

     if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1)
         handle_error("sigprocmask");

     sfd = signalfd(-1, &mask, 0);
     if (sfd == -1)
         handle_error("signalfd");

     for (;;) {
         s = read(sfd, &fdsi, sizeof(struct signalfd_siginfo));
         if (s != sizeof(struct signalfd_siginfo))
             handle_error("read");

         if (fdsi.ssi_signo == SIGINT) {
             printf("Got SIGINT\n");
         } else if (fdsi.ssi_signo == SIGQUIT) {
             printf("Got SIGQUIT\n");
             exit(EXIT_SUCCESS);
         } else {
             printf("Read unexpected signal\n");
         }
     }
 }

 $ ./signalfd_demo
 ^CGot SIGINT
 ^CGot SIGINT
 ^\Got SIGQUIT

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-01-08 11:36:12 +02:00
Thomas Huth e9d49d518d linux-user/syscall: Replace g_malloc0 + memcpy with g_memdup
No need to use g_malloc0 to zero the memory if we memcpy to
the whole buffer afterwards anyway. Actually, there is even
a function which combines both steps, g_memdup, so let's use
this function here instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-11-06 15:42:38 +03:00
Stefan Weil d1c002b6ae linux-user: Remove type casts to union type
Casting to a union type is a gcc (and clang) extension. Other compilers
might not support it. This is not a problem today, but the type casts
can be removed easily. Smatch now no longer complains like before:

linux-user/syscall.c:3190:18: warning: cast to non-scalar
linux-user/syscall.c:7348:44: warning: cast to non-scalar

Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-10-08 19:46:47 +03:00
Markus Armbruster c78d65e8a7 linux-user: Use g_new() & friends where that makes obvious sense
g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).  Same Coccinelle semantic patch as in commit b45c03f.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-10-08 19:46:47 +03:00
Chen Gang 08703b9f7b linux-user/syscall.c: Add EAGAIN to host_to_target_errno_table for
Under Alpha host, EAGAIN is redefined to 35, so it need be remapped too.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-09-28 16:57:54 +03:00
Laurent Vivier 0f0426f343 linux-user: add name_to_handle_at/open_by_handle_at
This patch allows to run example given by open_by_handle_at(2):

      The following shell session demonstrates the use of these two programs:

           $ echo 'Can you please think about it?' > cecilia.txt
           $ ./t_name_to_handle_at cecilia.txt > fh
           $ ./t_open_by_handle_at < fh
           open_by_handle_at: Operation not permitted
           $ sudo ./t_open_by_handle_at < fh      # Need CAP_SYS_ADMIN
           Read 31 bytes
           $ rm cecilia.txt

       Now  we delete and (quickly) re-create the file so that it has the same
       content and (by chance) the  same  inode.[...]

           $ stat --printf="%i\n" cecilia.txt     # Display inode number
           4072121
           $ rm cecilia.txt
           $ echo 'Can you please think about it?' > cecilia.txt
           $ stat --printf="%i\n" cecilia.txt     # Check inode number
           4072121
           $ sudo ./t_open_by_handle_at < fh
           open_by_handle_at: Stale NFS file handle

See the man page for source code.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-09-28 16:44:46 +03:00
Timothy E Baldwin 93b4eff80a linux-user: Return target error number in do_fork()
Whilst calls to do_fork() are wrapped in get_errno() this does not
translate return values.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-09-28 16:40:12 +03:00
Jonathan Neuschäfer ee1045877a linux-user: fix cmsg conversion in case of multiple headers
Currently, __target_cmsg_nxthdr compares a pointer derived from
target_cmsg against the msg_control field of target_msgh (through
subtraction).  This failed for me when emulating i386 code under x86_64,
because pointers in the host address space and pointers in the guest
address space were not the same.  This patch passes the initial value of
target_cmsg into __target_cmsg_nxthdr.

I found and fixed two more related bugs:
- __target_cmsg_nxthdr now returns the new cmsg pointer instead of the
  old one.
- tgt_space (in host_to_target_cmsg) doesn't count "sizeof (struct
  target_cmsghdr)" twice anymore.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-09-28 16:39:43 +03:00
Stefan Brüns 59baae9a62 linux-user: remove MAX_ARG_PAGES limit
Instead of creating a temporary copy for the whole environment and
the arguments, directly copy everything to the target stack.

For this to work, we have to change the order of stack creation and
copying the arguments.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-09-28 16:29:11 +03:00
Chen Gang 704eff6c23 linux-user: Conditionalize syscalls which are not defined in tilegx
Some of architectures (e.g. tilegx), several syscall macros are not
supported, so switch them.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <BLU436-SMTP457D6FC9B2B9BA87AEB22CB9660@phx.gbl>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-09-15 07:41:35 -07:00
Peter Maydell a2aa09e181 * Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
 * cutils: qemu_strto* wrappers
 * iohandler.c simplification
 * Many other fixes and misc patches.
 
 And some MTTCG work (with Emilio's fixes squashed):
 * Signal-free TCG kick
 * Removing spinlock in favor of QemuMutex
 * User-mode emulation multi-threading fixes/docs
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
* cutils: qemu_strto* wrappers
* iohandler.c simplification
* Many other fixes and misc patches.

And some MTTCG work (with Emilio's fixes squashed):
* Signal-free TCG kick
* Removing spinlock in favor of QemuMutex
* User-mode emulation multi-threading fixes/docs

# gpg: Signature made Thu 10 Sep 2015 09:03:07 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream: (44 commits)
  cutils: work around platform differences in strto{l,ul,ll,ull}
  cpu-exec: fix lock hierarchy for user-mode emulation
  exec: make mmap_lock/mmap_unlock globally available
  tcg: comment on which functions have to be called with mmap_lock held
  tcg: add memory barriers in page_find_alloc accesses
  remove unused spinlock.
  replace spinlock by QemuMutex.
  cpus: remove tcg_halt_cond and tcg_cpu_thread globals
  cpus: protect work list with work_mutex
  scripts/dump-guest-memory.py: fix after RAMBlock change
  configure: Add support for jemalloc
  add macro file for coccinelle
  configure: factor out adding disas configure
  vhost-scsi: fix wrong vhost-scsi firmware path
  checkpatch: remove tests that are not relevant outside the kernel
  checkpatch: adapt some tests to QEMU
  CODING_STYLE: update mixed declaration rules
  qmp: Add example usage of strto*l() qemu wrapper
  cutils: Add qemu_strtoull() wrapper
  cutils: Add qemu_strtoll() wrapper
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-09-14 16:13:16 +01:00
Veres Lajos 67cc32ebfd typofixes - v4
Signed-off-by: Veres Lajos <vlajos@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:45:43 +03:00
Emilio G. Cota 7090376369 linux-user: call rcu_(un)register_thread on pthread_(exit|create)
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1440375847-17603-13-git-send-email-cota@braap.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09 15:34:54 +02:00
Laurent Vivier 45c874ebba linux-user: ioctl() command type is int
When executing a 64bit target chroot on 64bit host,
the ioctl() command can mismatch.

It seems the previous commit doesn't solve the problem in
my case:

    9c6bf9c7 linux-user: Fix ioctl cmd type mismatch on 64-bit targets

For example, a ppc64 chroot on an x86_64 host:

bash-4.3# ls
Unsupported ioctl: cmd=0x80087467
Unsupported ioctl: cmd=0x802c7415

The origin of the problem is in syscall.c:do_ioctl().

    static abi_long do_ioctl(int fd, abi_long cmd, abi_long arg)

In this case (ppc64) abi_long is long (on the x86_64), and

    cmd = 0x0000000080087467

then
    if (ie->target_cmd == cmd)

target_cmd is int, so target_cmd = 0x80087467
and to compare an int with a long, the sign is extended to 64bit,
so the comparison is:

    if (0xffffffff80087467 == 0x0000000080087467)

which doesn't match whereas it should.

This patch uses int in the case of the target command type
instead of abi_long.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-06-16 09:37:17 +03:00
Peter Maydell 876e23cb2e linux-user: use __get_user and __put_user in cmsg conversions
The target payloads in cmsg conversions may not have the alignment
required by the host. Using the get_user and put_user functions is
the easiest way to handle this and also do the byte-swapping we
require.

(Note that prior to this commit target_to_host_cmsg was incorrectly
using __put_user() rather than __get_user() for the SCM_CREDENTIALS
conversion, which meant it wasn't getting the benefit of the
misalignment handling.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-06-16 08:21:01 +03:00
Peter Maydell c2aeb2586b linux-user: Fix length handling in host_to_target_cmsg
The previous code for handling payload length when converting
cmsg structures from host to target had a number of problems:
 * we required the msg->msg_controllen to declare the buffer
   to have enough space for final trailing padding (we were
   checking against CMSG_SPACE), whereas the kernel does not
   require this, and common userspace code assumes this. (In
   particular, glibc's "try to talk to nscd" code that it will
   run on startup will receive a cmsg with a 4 byte payload and
   only allocate 4 bytes for it, which was causing us to do
   the wrong thing on architectures that need 8-alignment.)
 * we weren't correctly handling the fact that the SO_TIMESTAMP
   payload may be larger for the target than the host
 * we weren't marking the messages with MSG_CTRUNC when we did
   need to truncate a message that wasn't truncated by the host,
   but were instead logging a QEMU message; since truncation is
   always the result of a guest giving us an insufficiently
   sized buffer, we should report it to the guest as the kernel
   does and don't log anything

Rewrite the parts of the function that deal with length to
fix these issues, and add a comment in target_to_host_cmsg
to explain why the overflow logging it does is a QEMU bug,
not a guest issue.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-06-16 08:21:01 +03:00
Alexander Graf 8be656b87c linux-user: Allocate thunk size dynamically
We store all struct types in an array of static size without ever
checking whether we overrun it. Of course some day someone (like me
in another, ancient ALSA enabling patch set) will run into the limit
without realizing it.

So let's make the allocation dynamic. We already know the number of
structs that we want to allocate, so we only need to pass the variable
into the respective piece of code.

Also, to ensure we don't accidently overwrite random memory, add some
asserts to sanity check whether a thunk is actually part of our array.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-06-15 11:36:58 +03:00
Paolo Bonzini a59629fcc6 rcu: do not create thread in pthread_atfork callback
If QEMU forks after the CPU threads have been created, qemu_mutex_lock_iothread
will not be able to do qemu_cpu_kick_thread.  There is no solution other than
assuming that forks after the CPU threads have been created will end up in an
exec.  Forks before the CPU threads have been created (such as -daemonize)
have to call rcu_after_fork manually.

Notably, the oxygen theme for GTK+ forks and shows a "No such process" error
without this patch.

This patch can be reverted once the iothread loses the "kick the TCG thread"
magic.

User-mode emulation does not use the iothread, so it can also call
rcu_after_fork.

Reported by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-01 10:06:38 +02:00
Andreas Schwab 17644b3627 linux-user: fix emulation of splice syscall
The second and fourth argument are in/out parameters, store them back
after the syscall.  Also, the fourth argument was mishandled, and EFAULT
handling was missing.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2015-03-22 15:18:51 +02:00
Chen Gang S dec0473dc6 linux-user/syscall.c: do_ioctl_dm: Need to call unlock_user() before going to failure return in default case
In abi_long do_ioctl_dm(), after lock_user() call, the code does
not call unlock_user() before going to failure return in default case.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-02-10 09:27:20 +03:00