This patch implements Qemu user mode syncfs() syscall support. Syscall
syncfs() syncs the filesystem containing file determined by the open
file descriptor passed as the argument to syncfs().
The implementation consists of a straightforward invocation of host's
syncfs(). Configure and strace support is included as well.
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This patch implements Qemu user mode clock_adjtime() syscall support.
The implementation is based on invocation of host's clock_adjtime().
Signed-off-by: Aleksandar Rikalo <aleksandar.rikalo@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The epoll event array which epoll_wait() allocates has a size
determined by the guest which could potentially be quite large.
Use g_try_new() rather than alloca() so that we can fail more
cleanly if the guest hands us an oversize value. (ENOMEM is
not a documented return value for epoll_wait() but in practice
some kernel configurations can return it -- see for instance
sys_oabi_epoll_wait() on ARM.)
This rearrangement includes fixing a bug where we were
incorrectly passing a negative length to unlock_user() in
the error-exit codepath.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Used by fedora21 on ppc64 in the network initialization
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
There are currently several problems related to syslog() support.
For example, if the second argument "bufp" of target syslog() syscall
is NULL, the current implementation always returns error code EFAULT.
However, NULL is a perfectly valid value for the second argument for
many use cases of this syscall. This is, for example, visible from
this excerpt of man page for syslog(2):
> EINVAL Bad arguments (e.g., bad type; or for type 2, 3, or 4, buf is
> NULL, or len is less than zero; or for type 8, the level is
> outside the range 1 to 8).
Moreover, the argument "bufp" is ignored for all cases of values of the
first argument, except 2, 3 and 4. This means that for such cases
(the first argument is not 2, 3 or 4), there is no need to pass "buf"
between host and target, and it can be set to NULL while calling host's
syslog(), without loss of emulation accuracy.
Note also that if "bufp" is NULL and the first argument is 2, 3 or 4, the
correct returned error code is EINVAL, not EFAULT.
All these details are reflected in this patch.
"#ifdef TARGET_NR_syslog" is also proprerly inserted when needed.
Support for Qemu's "-strace" switch for syslog() syscall is included too.
LTP tests syslog11 and syslog12 pass with this patch (while fail without
it), on any platform.
Changes to original patch by Riku Voipio:
fixed error paths in TARGET_SYSLOG_ACTION_READ_ALL to match
http://lxr.free-electrons.com/source/kernel/printk/printk.c?v=4.7#L1335
Should fix also the build error in:
https://lists.gnu.org/archive/html/qemu-devel/2016-10/msg03721.html
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Since not all Linux host platforms support socketcall() (most notably
Intel), do_socketcall() function in Qemu's syscalls.c is implemented to
mirror the corespondant implementation of socketcall() in Linux kernel,
and to utilise individual socket operations that are supported on all
Linux platforms. (see kernel source file net/socket.c, definition of
socketcall).
However, error codes produced by Qemu implementation are wrong for the
cases of invalid values of the first argument. Also, naming of constants
is not consistent with kernel one, and not consistant with Qemu convention
of prefixing such constants with "TARGET_". This patch in that light
brings do_socketcall() closer to its kernel counterpart, and in that way
fixes the errors and yields more consisrtent Qemu code.
There were also three missing cases (among 20) for strace support for
socketcall(). The array that contains pointers for appropriate printing
functions is updated with 3 elements, however pointers to functions are
left NULL, and its implementation is left for future.
Also, this patch fixes failure of LTP test socketcall02, if executed on some
Qemu emulated sywstems (uer mode).
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
If syscalls msgrcv() and msgsnd() fail, they return E2BIG, EACCES,
EAGAIN, EFAULT, EIDRM, EINTR, EINVAL, ENOMEM, or ENOMSG.
By examining negative scenarios of these syscalls for Mips, it was
established that ENOMSG does not have the same value accross all
platforms, but it is nevertheless not included for conversion in
the correspondant conversion table defined in linux-user/syscall.c.
This is certainly a bug, since it leads to the incorrect emulation
of msgrcv() and msgsnd() for scenarios involving ENOMSG.
This patch fixes this by extending the conversion table to include
ENOMSG.
Also, LTP test msgrcv04 will be fixed for some platforms.
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Conversion of file creation flags (O_CREAT, ...) from target to host
was missing.
Also, this patch implements better error handling.
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This patch implements Qemu user mode adjtimex() syscall support.
Syscall adjtimex() reads and optionally sets parameters for a clock
adjustment algorithm used in network synchonization or similar scenarios.
Its declaration is:
int adjtimex(struct timex *buf);
The correspondent source code in the Linux kernel is at kernel/time.c,
line 206.
The Qemu implementation is based on invocation of host's adjtimex(), and
its key part is in the "TARGET_NR_adjtimex" case segment of the the main
switch statement of the function do_syscall(), in linux-user/syscalls.c. All
necessary conversions of the data structures from target to host and from
host to target are covered. Two new functions, target_to_host_timex() and
host_to_target_timex(), are provided for the purpose of such conversions.
For that purpose, the support for related structure "timex" had tp be added
to the file linux-user/syscall_defs.h, based on its definition in Linux
kernel. Also, the relevant support for "-strace" Qemu option is included
in files linux-user/strace.c and linux-user/strace.list.
This patch also fixes failures of LTP tests adjtimex01 and adjtimex02, if
executed in Qemu user mode.
Signed-off-by: Aleksandar Rikalo <aleksandar.rikalo@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
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Merge remote-tracking branch 'remotes/mjt/tags/trivial-patches-fetch' into staging
trivial patches for 2016-10-08
# gpg: Signature made Sat 08 Oct 2016 09:56:38 BST
# gpg: using RSA key 0x701B4F6B1A693E59
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg: aka "Michael Tokarev <mjt@corpit.ru>"
# gpg: aka "Michael Tokarev <mjt@debian.org>"
# Primary key fingerprint: 6EE1 95D1 886E 8FFB 810D 4324 457C E0A0 8044 65C5
# Subkey fingerprint: 7B73 BAD6 8BE7 A2C2 8931 4B22 701B 4F6B 1A69 3E59
* remotes/mjt/tags/trivial-patches-fetch: (26 commits)
net/filter-mirror: Fix mirror initial check typo
virtio: rename the bar index field name in VirtIOPCIProxy
linux-user: include <poll.h> instead of <sys/poll.h>
char: fix missing return in error path for chardev TLS init
CODING_STYLE: Fix a typo ("have" vs. "has")
bitmap: refine and move BITMAP_{FIRST/LAST}_WORD_MASK
build-sys: fix find-in-path
m68k: change default system clock for m5208evb
exec: remove unused compacted argument
usb: ehci: fix memory leak in ehci_process_itd
qapi: make the json schema files more regular.
maint: Add module_block.h to .gitignore
MAINTAINERS: Some updates related to the SH4 machines
MAINTAINERS: Add some more MIPS related files
MAINTAINERS: Add usermode related config files
MAINTAINERS: Add some more pattern to recognize all win32 related files
MAINTAINERS: Add some more rocker related files
MAINTAINERS: Add header files to CRIS section
MAINTAINERS: Add some more files to the virtio section
MAINTAINERS: Add some SPARC machine related files
...
# Conflicts:
# MAINTAINERS
This removes the last usage of <sys/poll.h> in the code base.
Signed-off-by: Felix Janda <felix.janda@posteo.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
There is a potential race if several threads exit at once. To serialise
the exits extend the lock above the initial checking of the CPU list.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20160930213106.20186-11-alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
EDQUOT is defined for Mips platform in Linux kernel in such a way
that it has different value than on most other platforms. However,
correspondent TARGET_EDQUOT for Mips is missing in Qemu code. Moreover,
TARGET_EDQUOT is missing from the table for conversion of error codes
from host to target. This patch fixes these problems.
Without this patch, syscalls add_key(), keyctl(), link(), mkdir(), mknod(),
open(), rename(), request_key(), setxattr(), symlink(), and write() will not
be able to return the right error code in some scenarios on Mips platform.
(Some of these syscalls are not yet supported in Qemu, but once they are
supported, they will need correct EDQUOT handling.)
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
The function that is changed in this patch is supposed to indicate that
there was certain argument rearrangement related to 64-bit arguments on
32-bit platforms. The background on such rearrangements can be found,
for example, in the man page for syscall(2).
However, for 64-bit Mips architectures there is no such rearrangement,
and this patch reflects it.
Signed-off-by: Aleksandar Rikalo <aleksandar.rikalo@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
TARGET_NR_select can have three different implementations:
1- to always return -ENOSYS
microblaze, ppc, ppc64
-> TARGET_WANT_NI_OLD_SELECT
2- to take parameters from a structure pointed by arg1
(kernel sys_old_select)
i386, arm, m68k
-> TARGET_WANT_OLD_SYS_SELECT
3- to take parameters from arg[1-5]
(kernel sys_select)
x86_64, alpha, s390x,
cris, sparc, sparc64
Some (new) architectures don't define NR_select,
4- but only NR__newselect with sys_select:
mips, mips64, sh
5- don't define NR__newselect, and use pselect6 syscall:
aarch64, openrisc, tilegx, unicore32
Reported-by: Timothy Pearson <tpearson@raptorengineering.com>
Reported-by: Allan Wirth <awirth@akamai.com>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
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>
We currently make no checks on the flags passed to the clone syscall,
which means we will not fail clone attempts which ask for features
that we can't implement. Add sanity checking of the flags to clone
(which we were already doing in the "this is a fork" path, but not
for the "this is a new thread" path), tidy up the checking in
the fork path to match it, and check that the fork case isn't trying
to specify a custom termination signal.
This is helpful in causing some LTP test cases to fail cleanly
rather than behaving bizarrely when we let the clone succeed
but didn't provide the semantics requested by the flags.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The 'nptl_flags' variable in do_fork() is set to a copy of
'flags', and then the CLONE_NPTL_FLAGS are cleared out of 'flags'.
However the only effect of this is that the later check on
"if (flags & CLONE_PARENT_SETTID)" is never true. Since we
will already have done the setting of parent_tidptr in clone_func()
in the child thread, we don't need to do it again.
Delete the dead if() and the clearing of CLONE_NPTL_FLAGS from
'flags', and then use 'flags' where we were previously using
'nptl_flags', so we can delete the unnecessary variable.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Instead of assuming in queue_signal() that all callers are passing
a siginfo structure which uses the _sifields._sigfault part of the
union (and thus a si_type of QEMU_SI_FAULT), make callers pass
the si_type they require in as an argument.
[RV adjusted to apply]
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The shmat() handling needs to do target-specific handling
of the attach address for shmat():
* if the SHM_RND flag is passed, the address is rounded
down to a SHMLBA boundary
* if SHM_RND is not passed, then the call is failed EINVAL
if the address is not a multiple of SHMLBA
Since SHMLBA is target-specific, we need to do this
checking and rounding in QEMU and can't leave it up to the
host syscall.
Allow targets to define TARGET_FORCE_SHMLBA and provide
a target_shmlba() function if appropriate, and update
do_shmat() to honour them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
do_ioctl_dm() should return target errno values, not host ones;
correct an accidental use of a host errno in an error path.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
lock_user() can return NULL, which typically means the syscall
should fail with EFAULT. Add checks in various places where
Coverity spotted that we were missing them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Do an initial range check on the ppoll syscall's nfds argument,
to avoid possible overflow in the calculation of the lock_user()
size argument. The host kernel will later apply the rather lower
limit based on RLIMIT_NOFILE as appropriate.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The kernel checks that the maxevents parameter to epoll_wait
is non-negative and not larger than EP_MAX_EVENTS. Add this
check to our implementation, so that:
* we fail these cases EINVAL rather than EFAULT
* we don't pass negative or overflowing values to the
lock_user() size calculation
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The linux utimensat syscall differs in semantics from the
libc function because the syscall combines the features
of utimensat() and futimens(). Rather than trying to
split these apart in order to call the two libc functions
which then call the same underlying syscall, just always
directly make the host syscall. This fixes bugs in some
of the corner cases which should return errors from the
syscall but which we were incorrectly directing to futimens().
This doesn't reduce the set of hosts that our syscall
implementation will work on, because if the direct syscall
fails ENOSYS then the libc functions would also fail ENOSYS.
(The system call has been in the kernel since 2.6.22 anyway.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The POSIX standard mandates that for a connected socket recvfrom()
must ignore the msg_name and msg_namelen fields. This is awkward
for QEMU because we will attempt to copy them from guest address
space. Handle this by not immediately returning a TARGET_EFAULT
if the copy failed, but instead passing a known-bad address
to the host kernel, which can then return EFAULT or ignore the
value appropriately.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The sendmsg and recvmsg syscalls use a different errno to indicate
an overlarge iovec length from readv and writev. Handle this
special case in do_sendrcvmsg_locked() to avoid getting the
default errno returned by lock_iovec().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
In the kernel the length of an iovec is generally handled as
an unsigned long, not an integer; fix the parameter to
lock_iovec() accordingly.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
In 9c37146782 I've tried to fix a broken build with older
linux-headers. However, I didn't do it properly. The solution
implemented here is to grab the enums that caused the problem
initially, and rename their values so that they are "QEMU_"
prefixed. In order to guarantee matching values with actual
enums from linux-headers, the enums are seeded with starting
values from the original enums.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 75c14d6e8a97c4ff3931d69c13eab7376968d8b4.1471593869.git.mprivozn@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The fix I've made there was wrong. I mean, basically what I did
there was equivalent to:
#if 0
some code;
#endif
This reverts commit 9c37146782.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 40d61349e445c1ad5fef795da704bf7ed6e19c86.1471593869.git.mprivozn@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The llseek syscall takes two 32-bit arguments, offset_high
and offset_low, which must be combined to form a single
64-bit offset. Unfortunately we were combining them with
(uint64_t)arg2 << 32) | arg3
and arg3 is a signed type; this meant that when promoting
arg3 to a 64-bit type it would be sign-extended. The effect
was that if the offset happened to have bit 31 set then
this bit would get sign-extended into all of bits 63..32.
Explicitly cast arg3 to abi_ulong to avoid the erroneous
sign extension.
Reported-by: Chanho Park <parkch98@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Chanho Park <parkch98@gmail.com>
Message-id: 1470938379-1133-1-git-send-email-peter.maydell@linaro.org
In c5dff280 we tried to make us understand netlink messages more.
So we've added a code that does some translation. However, the
code assumed linux-headers to be at least version 4.4 of it
because most of the symbols there (if not all of them) were added
in just that release. This, however, breaks build on systems with
older versions of the package.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Message-id: 23806aac6db3baf7e2cdab4c62d6e3468ce6b4dc.1471340849.git.mprivozn@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In do_brk(), we were inadvertently truncating the size
of a requested brk() from the guest by putting it into an
'int' variable. This meant that we would incorrectly report
success back to the guest rather than a failed allocation,
typically resulting in the guest then segfaulting. Use
abi_ulong instead.
This fixes a crash in the '31370.cc' test in the gcc libstdc++ test
suite (the test case starts by trying to allocate a very large
size and reduces the size until the allocation succeeds).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The target_semid_ds structure is not correct for all
architectures: the padding fields should only exist for:
* 32-bit ABIs
* x86
It is also misnamed, since it is following the kernel
semid64_ds structure (QEMU doesn't support the legacy
semid_ds structure at all). Rename the struct, provide
a correct generic definition and allow the oddball x86
architecture to provide its own version.
This fixes broken SYSV semaphores for all our 64-bit
architectures except x86 and ppc.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Use g_strlcpy() rather than strcpy() to copy the uname string
into the structure we return to the guest for the uname syscall.
This avoids overrunning the buffer if the user passed us an
overlong string via the QEMU command line.
We fix a comment typo while we're in the neighbourhood.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
In open_self_cmdline() we look for a 0 in the buffer we read
from /prc/self/cmdline. We were incorrectly passing the length
of our buf[] array to memchr() as the length to search, rather
than the number of bytes we actually read into it, which could
be shorter. This was spotted by Coverity (because it could
result in our trying to pass a negative length argument to
write()).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
If userspace specifies a short buffer for a target sockaddr,
the kernel will only copy in as much as it has space for
(or none at all if the length is zero) -- see the kernel
move_addr_to_user() function. Mimic this in QEMU's
host_to_target_sockaddr() routine.
In particular, this fixes a segfault running the LTP
recvfrom01 test, where the guest makes a recvfrom()
call with a bad buffer pointer and other parameters which
cause the kernel to set the addrlen to zero; because we
did not skip the attempt to swap the sa_family field we
segfaulted on the bad address.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Many syscalls which take a sigset_t argument also take an argument
giving the size of the sigset_t. The kernel insists that this
matches its idea of the type size and fails EINVAL if it is not.
Implement this logic in QEMU. (This mostly just means some LTP test
cases which check error cases now pass.)
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>
Nested types are used by the kernel to send link information and
protocol properties.
We can see following errors with "ip link show":
Unimplemented nested type 26
Unimplemented nested type 26
Unimplemented nested type 18
Unimplemented nested type 26
Unimplemented nested type 18
Unimplemented nested type 26
This patch implements nested types 18 (IFLA_LINKINFO) and
26 (IFLA_AF_SPEC).
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
As we convert sockaddr for AF_PACKET family for sendto() (target to
host) we need also to convert this for getsockname() (host to target).
arping uses getsockname() to get the the interface address and uses
this address with sendto().
Tested with:
/sbin/arping -D -q -c2 -I eno1 192.168.122.88
...
getsockname(3, {sa_family=AF_PACKET, proto=0x806, if2,
pkttype=PACKET_HOST, addr(6)={1, 10c37b6b9a76}, [18]) = 0
...
sendto(3, "..." 28, 0,
{sa_family=AF_PACKET, proto=0x806, if2, pkttype=PACKET_HOST,
addr(6)={1, ffffffffffff}, 20) = 28
...
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Netlink is byte-swapping data in the guest memory (it's bad).
It's ok when the data come from the host as they are generated by the
host.
But it doesn't work when data come from the guest: the guest can
try to reuse these data whereas they have been byte-swapped.
This is what happens in glibc:
glibc generates a sequence number in nlh.nlmsg_seq and calls
sendto() with this nlh. In sendto(), we byte-swap nlmsg.seq.
Later, after the recvmsg(), glibc compares nlh.nlmsg_seq with
sequence number given in return, and of course it fails (hangs),
because nlh.nlmsg_seq is not valid anymore.
The involved code in glibc is:
sysdeps/unix/sysv/linux/check_pf.c:make_request()
...
req.nlh.nlmsg_seq = time (NULL);
...
if (TEMP_FAILURE_RETRY (__sendto (fd, (void *) &req, sizeof (req), 0,
(struct sockaddr *) &nladdr,
sizeof (nladdr))) < 0)
<here req.nlh.nlmsg_seq has been byte-swapped>
...
do
{
...
ssize_t read_len = TEMP_FAILURE_RETRY (__recvmsg (fd, &msg, 0));
...
struct nlmsghdr *nlmh;
for (nlmh = (struct nlmsghdr *) buf;
NLMSG_OK (nlmh, (size_t) read_len);
nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len))
{
<we compare nlmh->nlmsg_seq with corrupted req.nlh.nlmsg_seq>
if (nladdr.nl_pid != 0 || (pid_t) nlmh->nlmsg_pid != pid
|| nlmh->nlmsg_seq != req.nlh.nlmsg_seq)
continue;
...
else if (nlmh->nlmsg_type == NLMSG_DONE)
/* We found the end, leave the loop. */
done = true;
}
}
while (! done);
As we have a continue on "nlmh->nlmsg_seq != req.nlh.nlmsg_seq",
"done" cannot be set to "true" and we have an infinite loop.
It's why commands like "apt-get update" or "dnf update hangs".
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
fd_trans_target_to_host_data() and fd_trans_host_to_target_data() must
return the length of processed data.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Older kernels don't have F_SETPIPE_SZ and F_GETPIPE_SZ (in
particular RHEL6's system headers don't define these). Add
ifdefs so that we can gracefully fall back to not supporting
those guest ioctls rather than failing to build.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 1467304429-21470-1-git-send-email-peter.maydell@linaro.org
Adds two events to trace syscalls in syscall emulation mode (*-user):
* guest_user_syscall: Emitted before the syscall is emulated; contains
the syscall number and arguments.
* guest_user_syscall_ret: Emitted after the syscall is emulated;
contains the syscall number and return value.
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 146651712411.12388.10024905980452504938.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If the structure pointed by NLMSG_DATA() is bigger
than the size of NLMSG_DATA(), don't swap its fields
to avoid memory corruption.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
if we process the whole buffer, the netlink helpers can try
to swap invalid data.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Support the F_GETPIPE_SZ and F_SETPIPE_SZ fcntl operations.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
