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* linux-user: Use direct syscalls for setuid(), etcPeter Maydell2016-05-271-12/+46
| | | | | | | | | | | | | | | | On Linux the setuid(), setgid(), etc system calls have different semantics from the libc functions. The libc functions follow POSIX and update the credentials for all threads in the process; the system calls update only the thread which makes the call. (This impedance mismatch is worked around in libc by signalling all threads to tell them to do a syscall, in a byzantine and fragile way; see http://ewontfix.com/17/.) Since in linux-user we are trying to emulate the system call semantics, we must implement all these syscalls to directly call the underlying host syscall, rather than calling the host libc function. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
* linux-user: Use g_try_malloc() in do_msgrcv()Peter Maydell2016-05-271-1/+5
| | | | | | | | | | 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>
* linux-user: Handle msgrcv error case correctlyPeter Maydell2016-05-271-1/+5
| | | | | | | | | | | | | | | | | | | 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>
* linux-user: Handle negative values in timespec conversionPeter Maydell2016-05-271-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: Use safe_syscall for futex syscallPeter Maydell2016-05-271-8/+10
| | | | | | | | | | | | | | | 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>
* linux-user: Use safe_syscall for pselect, select syscallsPeter Maydell2016-05-271-17/+19
| | | | | | | | | | | | | | | 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>
* linux-user: Use safe_syscall for execve syscallTimothy E Baldwin2016-05-271-1/+12
| | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: Use safe_syscall for wait system callsTimothy E Baldwin2016-05-271-3/+7
| | | | | | | | | | | | | 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>
* linux-user: Use safe_syscall for open and openat system callsTimothy E Baldwin2016-05-271-14/+4Star
| | | | | | | | | | | 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>
* linux-user: Use safe_syscall for read and write system callsTimothy E Baldwin2016-05-271-2/+5
| | | | | | | | | | | 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>
* linux-user: Provide safe_syscall for fixing races between signals and syscallsTimothy E Baldwin2016-05-271-0/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: Add debug code to exercise restarting system callsTimothy E Baldwin2016-05-271-0/+19
| | | | | | | | | | | | | | | 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>
* linux-user: Support for restarting system calls for x86 targetsTimothy E Baldwin2016-05-271-2/+0Star
| | | | | | | | | | | | | | | | 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>
* linux-user: Consistently return host errnos from do_openat()Peter Maydell2016-05-271-4/+10
| | | | | | | | | | | | 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>
* linux-user: Check array bounds in errno conversionTimothy E Baldwin2016-05-271-2/+6
| | | | | | | | | | | 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>
* util: move declarations out of qemu-common.hVeronia Bahaa2016-03-221-0/+2
| | | | | | | | | | 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>
* linux-user: add getrandom() syscallLaurent Vivier2016-02-241-0/+13
| | | | | | | | 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>
* linux-user: remove unavailable syscalls from aarch64Riku Voipio2016-02-231-2/+0Star
| | | | | | | | | | 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>
* linux-user: Don't assert if guest tries shmdt(0)Peter Maydell2016-02-231-5/+7
| | | | | | | | | | | | | | | | | 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>
* linux-user: fix realloc size of target_fd_trans.Laurent Vivier2016-02-231-2/+2
| | | | | | | | | 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>
* linux-user: Clean up includesPeter Maydell2016-01-291-13/+1Star
| | | | | | | | | | 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
* linux-user: Add SOCKOP_sendmmsg and SOCKOP_recvmmsg socket call, wire them up.John Paul Adrian Glaubitz2016-01-111-2/+6
| | | | | | | | | | | | | | 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>
* linux-user/syscall.c: Use SOL_SOCKET instead of level for setsockopt()Chen Gang2016-01-111-1/+2
| | | | | | | | | 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>
* linux-user: enable sigaltstack for all architecturesMichael Tokarev2016-01-081-6/+0Star
| | | | | | | | | | | | | | 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>
* linux-user: check fd is >= 0 in ↵Laurent Vivier2016-01-081-2/+2
| | | | | | | 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>
* linux-user: manage bind with a socket of SOCK_PACKET type.Laurent Vivier2016-01-081-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: add a function hook to translate sockaddrLaurent Vivier2016-01-081-6/+21
| | | | | Signed-off-by: Laurent Vivier <laurent@vivier.eu> Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
* linux-user: rename TargetFdFunc to TargetFdDataFunc, and structure fields ↵Laurent Vivier2016-01-081-9/+9
| | | | | | | | 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>
* linux-user: SOCK_PACKET uses network endian to encode protocol in socket()Laurent Vivier2016-01-081-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user/syscall.c: malloc()/calloc() to g_malloc()/g_try_malloc()/g_new0()Harmandeep Kaur2016-01-081-15/+15
| | | | | | | | | | | 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>
* linux-user: in poll(), if nfds is 0, pfd can be NULLLaurent Vivier2016-01-081-7/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: add signalfd/signalfd4 syscallsLaurent Vivier2016-01-081-0/+167
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user/syscall: Replace g_malloc0 + memcpy with g_memdupThomas Huth2015-11-061-2/+1Star
| | | | | | | | | | | 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>
* linux-user: Remove type casts to union typeStefan Weil2015-10-081-4/+4
| | | | | | | | | | | | | 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>
* linux-user: Use g_new() & friends where that makes obvious senseMarkus Armbruster2015-10-081-1/+1
| | | | | | | | | | | | | | | 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>
* linux-user/syscall.c: Add EAGAIN to host_to_target_errno_table forChen Gang2015-09-281-0/+1
| | | | | | | | 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>
* linux-user: add name_to_handle_at/open_by_handle_atLaurent Vivier2015-09-281-0/+98
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: Return target error number in do_fork()Timothy E Baldwin2015-09-281-2/+3
| | | | | | | | | 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>
* linux-user: fix cmsg conversion in case of multiple headersJonathan Neuschäfer2015-09-281-5/+9
| | | | | | | | | | | | | | | | | | | 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>
* linux-user: remove MAX_ARG_PAGES limitStefan Brüns2015-09-281-6/+0Star
| | | | | | | | | | | | 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>
* linux-user: Conditionalize syscalls which are not defined in tilegxChen Gang2015-09-151-1/+49
| | | | | | | | | | 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>
* Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into stagingPeter Maydell2015-09-141-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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>
| * linux-user: call rcu_(un)register_thread on pthread_(exit|create)Emilio G. Cota2015-09-091-0/+2
| | | | | | | | | | | | 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>
* | typofixes - v4Veres Lajos2015-09-111-1/+0Star
|/ | | | | Signed-off-by: Veres Lajos <vlajos@gmail.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
* linux-user: ioctl() command type is intLaurent Vivier2015-06-161-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: use __get_user and __put_user in cmsg conversionsPeter Maydell2015-06-161-9/+11
| | | | | | | | | | | | | | | 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>
* linux-user: Fix length handling in host_to_target_cmsgPeter Maydell2015-06-161-8/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: Allocate thunk size dynamicallyAlexander Graf2015-06-151-0/+3
| | | | | | | | | | | | | | | | | 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>
* rcu: do not create thread in pthread_atfork callbackPaolo Bonzini2015-04-011-0/+1
| | | | | | | | | | | | | | | | | | | | | 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>
* linux-user: fix emulation of splice syscallAndreas Schwab2015-03-221-4/+18
| | | | | | | | | | 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>