In qemu we catch accesses to files like /proc/cpuinfo or /proc/net/route
and return to the guest contents which would be visible on a real system
(instead what the host would show).
This patch fixes a bug, where for example the accesses
cat /proc////cpuinfo
or
cd /proc && cat cpuinfo
will not be recognized by qemu and where qemu will wrongly show
the contents of the host's /proc/cpuinfo file.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230803214450.647040-2-deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Rather than using a zero tuple to end the table, use a macro
to apply ARRAY_SIZE and pass that on to the convert functions.
This fixes two bugs in which the conversion functions required
that both the target and host masks be non-zero in order to
continue, rather than require both target and host masks be
zero in order to terminate.
This affected mmap_flags_tbl when the host does not support
all of the flags we wish to convert (e.g. MAP_UNINITIALIZED).
Mapping these flags to zero is good enough, and matches how
the kernel ignores bits that are unknown.
Fixes: 4b840f96 ("linux-user: Populate more bits in mmap_flags_tbl")
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
New function that rejects unsupported map types and flags.
In 4b840f96 we should not have accepted MAP_SHARED_VALIDATE
without actually validating the rest of the flags.
Fixes: 4b840f96 ("linux-user: Populate more bits in mmap_flags_tbl")
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We will want to be able to search the set of mappings.
For this patch, the two users iterate the tree in order.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
do_brk() minimizes calls into target_mmap() by aligning the address
with host page size, which is potentially larger than the target page
size. However, the current implementation of this optimization has two
bugs:
- The start of brk is rounded up with the host page size while brk
advertises an address aligned with the target page size as the
beginning of brk. This makes the beginning of brk unmapped.
- Content clearing after mapping is flawed. The size to clear is
specified as HOST_PAGE_ALIGN(brk_page) - brk_page, but brk_page is
aligned with the host page size so it is always zero.
This optimization actually has no practical benefit. It makes difference
when brk() is called multiple times with values in a range of the host
page size. However, sophisticated memory allocators try to avoid to
make such frequent brk() calls. For example, glibc 2.37 calls brk() to
shrink the heap only when there is a room more than 128 KiB. It is
rare to have a page size larger than 128 KiB if it happens.
Let's remove the optimization to fix the bugs and make the code simpler.
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1616
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-7-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Linux 6.4.7 does nothing when a value smaller than the initial brk is
specified.
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-6-akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
MAP_FIXED_NOREPLACE can ensure the mapped address is fixed without
concerning that the new mapping overwrites something else.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-5-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Later the returned value is compared with -1, and negated errno is not
expected.
Fixes: 00faf08c95 ("linux-user: Don't use MAP_FIXED in do_brk()")
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-4-akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Fix the math overflow when calculating the new_malloc_size.
new_host_brk_page and brk_page are unsigned integers. If userspace
reduces the heap, new_host_brk_page is lower than brk_page which results
in a huge positive number (but should actually be negative).
Fix it by adding a proper check and as such make the code more readable.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
Since commit 86f04735ac ("linux-user: Fix brk() to release pages") it's
possible for userspace applications to reduce their memory footprint by
calling brk() with a lower address and free up memory. Before that commit
guest heap memory was never unmapped.
But the Linux kernel prohibits to reduce brk() below the initial memory
address which is set at startup by the set_brk() function in binfmt_elf.c.
Such a range check was missed in commit 86f04735ac.
This patch adds the missing check by storing the initial brk value in
initial_target_brk and verify any new brk addresses against that value.
Tested with the i386 upx binary from
https://github.com/upx/upx/releases/download/v4.0.2/upx-4.0.2-i386_linux.tar.xz
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
The qemu brk() implementation is too aggressive and cleans remaining bytes
on the current page above the last brk address.
But some existing applications are buggy and read/write bytes above their
current heap address. On a phyiscal machine this does not trigger a
runtime error as long as the access happens on the same page. Additionally
the Linux kernel allocates only full pages and does no zeroing on already
allocated pages, even if the brk address is lowered.
Fix qemu to behave the same way as the kernel does. Do not touch already
allocated pages, and - when running with different page sizes of guest and
host - zero out only those memory areas where the host page size is bigger
than the guest page size.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
In the code for TARGET_NR_clock_adjtime, we set the pointer phtx to
the address of the local variable htx. This means it can never be
NULL, but later in the code we check it for NULL anyway. Coverity
complains about this (CID 1507683) because the NULL check comes after
a call to clock_adjtime() that assumes it is non-NULL.
Since phtx is always &htx, and is used only in three places, it's not
really necessary. Remove it, bringing the code structure in to line
with that for TARGET_NR_clock_adjtime64, which already uses a simple
'&htx' when it wants a pointer to 'htx'.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230623144410.1837261-1-peter.maydell@linaro.org
These are types not used anymore anywhere else.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: <20230511085056.13809-1-quintela@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace the 0/-1 result with true/false.
Invert the sense of the test of all callers.
Document the function.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-25-richard.henderson@linaro.org>
We build with _FILE_OFFSET_BITS=64, so off_t = off64_t = uint64_t.
With an extra cast, this fixes emulation of mmap2, which could
overflow the computation of the full value of offset.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-14-richard.henderson@linaro.org>
Fix translation of TARGET_MAP_SHARED and TARGET_MAP_PRIVATE,
which are types not single bits. Add TARGET_MAP_SHARED_VALIDATE,
TARGET_MAP_SYNC, TARGET_MAP_NONBLOCK, TARGET_MAP_POPULATE,
TARGET_MAP_FIXED_NOREPLACE, and TARGET_MAP_UNINITIALIZED.
Update strace to match.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-9-richard.henderson@linaro.org>
The guest address, raddr, should be unsigned, aka abi_ulong.
The host addresses should be cast via *intptr_t not long.
Drop the inline and fix two other whitespace issues.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230626140250.69572-1-richard.henderson@linaro.org>
Support for execveat syscall was implemented in 55bbe4 and is available
since QEMU 8.0.0. It relies on host execveat, which is widely available
on most of Linux kernels today.
However, this change breaks qemu-user self emulation, if "host" qemu
version is less than 8.0.0. Indeed, it does not implement yet execveat.
This strange use case happens with most of distribution today having
binfmt support.
With a concrete failing example:
$ qemu-x86_64-7.2 qemu-x86_64-8.0 /bin/bash -c /bin/ls
/bin/bash: line 1: /bin/ls: Function not implemented
-> not implemented means execve returned ENOSYS
qemu-user-static 7.2 and 8.0 can be conveniently grabbed from debian
packages qemu-user-static* [1].
One usage of this is running wine-arm64 from linux-x64 (details [2]).
This is by updating qemu embedded in docker image that we ran into this
issue.
The solution to update host qemu is not always possible. Either it's
complicated or ask you to recompile it, or simply is not accessible
(GitLab CI, GitHub Actions). Thus, it could be worth to implement execve
without relying on execveat, which is the goal of this patch.
This patch was tested with example presented in this commit message.
[1] http://ftp.us.debian.org/debian/pool/main/q/qemu/
[1] https://www.linaro.org/blog/emulate-windows-on-arm/
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Message-Id: <20230705121023.973284-1-pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This patch adds the new syscall for the
"RISC-V Hardware Probing Interface"
(https://docs.kernel.org/riscv/hwprobe.html).
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Robbin Ehn <rehn@rivosinc.com>
Message-Id: <06a4543df2aa6101ca9a48f21a3198064b4f1f87.camel@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The Linux accept4() syscall allows two flags only: SOCK_NONBLOCK and
SOCK_CLOEXEC, and returns -EINVAL if any other bits have been set.
Change the qemu implementation accordingly, which means we can not use
the fcntl_flags_tbl[] translation table which allows too many other
values.
Beside the correction in behaviour, this actually fixes the accept4()
emulation for hppa, mips and alpha targets for which SOCK_NONBLOCK is
different than TARGET_SOCK_NONBLOCK (aka O_NONBLOCK).
The fix can be verified with the testcase of the debian lwt package,
which hangs forever in a read() syscall without this patch.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
When running a 32-bit guest on a 64-bit host, fcntl[64](F_GETFL) should
return with the TARGET_O_LARGEFILE flag set, because all 64-bit hosts
support large files unconditionally.
But on 64-bit hosts, O_LARGEFILE has the value 0, so the flag
translation can't be done with the fcntl_flags_tbl[]. Instead add the
TARGET_O_LARGEFILE flag afterwards.
Note that for 64-bit guests the compiler will optimize away this code,
since TARGET_O_LARGEFILE is zero.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
/proc/self/smaps is an extension of /proc/self/maps: it provides the
same lines, plus additional information about each range.
GDB uses /proc/self/smaps when available, which means that
generate-core-file tries it first before falling back to
/proc/self/maps. This, in turn, causes it to dump the host mappings,
since /proc/self/smaps is not emulated and is just passed through.
Fix by emulating /proc/self/smaps. Provide true values only for
Size, KernelPageSize, MMUPageSize and VmFlags. Leave all other values
at 0, which is a valid conservative estimate.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621203627.1808446-4-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-34-alex.bennee@linaro.org>
gdbstub cannot meaningfully handle QEMU_ERESTARTSYS, and it doesn't
need to. Add a parameter to do_guest_openat() that makes it use
openat() instead of safe_openat(), so that it becomes usable from
gdbstub.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621203627.1808446-3-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-33-alex.bennee@linaro.org>
These functions will be required by the GDB stub in order to provide
the guest view of /proc to GDB.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621203627.1808446-2-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-32-alex.bennee@linaro.org>
Coverity doesn't like the way we might end up calling getgroups()
with a NULL grouplist pointer. This is fine for the special case
of gidsetsize == 0, but we will also do it if the guest passes
us a negative gidsetsize. (CID 1512465)
Explicitly fail the negative gidsetsize with EINVAL, as the kernel
does. This means we definitely only call the libc getgroups()
with valid parameters. It also brings the getgroups() code in
to line with the setgroups() code.
Possibly Coverity may still complain about getgroups(0, NULL), but
that would be a false positive.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
There are 2 pairs of identical code (with different types)
for TARGET_NR_setgroups & TARGET_NR_setgroups32, and
for TARGET_NR_getgroups & TARGET_NR_getgroups32. Add
comments stating this fact, so that further modifications
are done in two places.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
linux-user getgroups(), setgroups(), getgroups32() and setgroups32()
used alloca() to allocate grouplist arrays, with unchecked gidsetsize
coming from the "guest". With NGROUPS_MAX being 65536 (linux, and it
is common for an application to allocate NGROUPS_MAX for getgroups()),
this means a typical allocation is half the megabyte on the stack.
Which just overflows stack, which leads to immediate SIGSEGV in actual
system getgroups() implementation.
An example of such issue is aptitude, eg
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=811087#72
Cap gidsetsize to NGROUPS_MAX (return EINVAL if it is larger than that),
and use heap allocation for grouplist instead of alloca(). While at it,
fix coding style and make all 4 implementations identical.
Try to not impose random limits - for example, allow gidsetsize to be
negative for getgroups() - just do not allocate negative-sized grouplist
in this case but still do actual getgroups() call. But do not allow
negative gidsetsize for setgroups() since its argument is unsigned.
Capping by NGROUPS_MAX seems a bit arbitrary, - we can do more, it is
not an error if set size will be NGROUPS_MAX+1. But we should not allow
integer overflow for the array being allocated. Maybe it is enough to
just call g_try_new() and return ENOMEM if it fails.
Maybe there's also no need to convert setgroups() since this one is
usually smaller and known beforehand (KERN_NGROUPS_MAX is actually 63, -
this is apparently a kernel-imposed limit for runtime group set).
The patch fixes aptitude segfault mentioned above.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Message-Id: <20230409105327.1273372-1-mjt@msgid.tls.msk.ru>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The kernel does not require PROT_READ for addresses passed to mincore.
For example the fincore(1) tool from util-linux uses PROT_NONE and
currently does not work under qemu-user.
Example (with fincore(1) from util-linux 2.38):
$ fincore /proc/self/exe
RES PAGES SIZE FILE
24K 6 22.1K /proc/self/exe
$ qemu-x86_64 /usr/bin/fincore /proc/self/exe
fincore: failed to do mincore: /proc/self/exe: Cannot allocate memory
With this patch:
$ ./build/qemu-x86_64 /usr/bin/fincore /proc/self/exe
RES PAGES SIZE FILE
24K 6 22.1K /proc/self/exe
Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20230422100314.1650-3-thomas@t-8ch.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20230424153429.276788-2-thomas@t-8ch.de>
[lv: move declaration at the beginning of the block,
define syscall]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The correct error number for unknown ioctls is ENOTTY.
ENOSYS would mean that the ioctl() syscall itself is not implemented,
which is very improbable and unexpected for userspace.
ENOTTY means "Inappropriate ioctl for device". This is what the kernel
returns on unknown ioctls, what qemu is trying to express and what
userspace is prepared to handle.
Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230426070659.80649-1-thomas@t-8ch.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
RISC-V does not expose all extensions via hwcaps, thus some userspace
applications may want to query these via /proc/cpuinfo.
Currently when querying this file the host's file is shown instead
which is slightly confusing. Emulate a basic /proc/cpuinfo file
with mmu info and an ISA string.
Signed-off-by: Afonso Bordado <afonsobordado@gmail.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <167873059442.9885.15152085316575248452-0@git.sr.ht>
[lv: removed the test that fails in CI for unknown reason]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Pass the address of the last byte to be changed, rather than
the first address past the last byte. This avoids overflow
when the last page of the address space is involved.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1528
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This had been pulled in from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-6-richard.henderson@linaro.org>
[AJB: also syscall-trace.h]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-16-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
Add emulation for the CLONE_PIDFD flag of the clone() syscall.
This flag was added in Linux kernel 5.2.
Successfully tested on a x86-64 Linux host with hppa-linux target.
Can be verified by running the testsuite of the qcoro debian package,
which breaks hard and kills the currently logged-in user without this
patch.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <Y4XoJCpvUA1JD7Sj@p100>
[lv: define CLONE_PIDFD if it is not]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
msync() uses the flags MS_ASYNC, MS_INVALIDATE and MS_SYNC, which differ
between platforms, specifcally on alpha and hppa.
Add a target to host translation for those and wire up a nicer strace
output.
This fixes the testsuite of the macaulay2 debian package with a hppa-linux
guest on a x86-64 host.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <Y5rMcts4qe15RaVN@p100>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The sin6_scope_id field uses the host byte order, so there is a
conversion to be made when host and target endianness differ.
Signed-off-by: Mathis Marion <mathis.marion@silabs.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230307154256.101528-2-Mathis.Marion@silabs.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The current brk() implementation does not de-allocate pages if a lower
address is given compared to earlier brk() calls.
But according to the manpage, brk() shall deallocate memory in this case
and currently it breaks a real-world application, specifically building
the debian gcl package in qemu-user.
Fix this issue by reworking the qemu brk() implementation.
Tested with the C-code testcase included in qemu commit 4d1de87c75, and
by building debian package of gcl in a hppa-linux guest on a x86-64
host.
Signed-off-by: Helge Deller <deller@gmx.de>
Message-Id: <Y6gId80ek49TK1xB@p100>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Some programs want to match an actual task state character.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <mvmedq2kxoe.fsf@suse.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
target_rlimit64 contains uint64_t fields, so it's 8-byte aligned on
some hosts, while some guests may align their respective type on a
4-byte boundary. This may lead to an unaligned access, which is an UB.
Fix by defining the fields as abi_ullong. This makes the host alignment
match that of the guest, and lets the compiler know that it should emit
code that can deal with the guest alignment.
While at it, also use __get_user() and __put_user() instead of
tswap64().
Fixes: 163a05a839 ("linux-user: Implement prlimit64 syscall")
Reported-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20230224003907.263914-2-iii@linux.ibm.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
When reading the expiration count from a timerfd, the endianness of the
64bit value read is the one of the host, just as for eventfds.
Signed-off-by: Mathis Marion <mathis.marion@silabs.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20230220085822.626798-2-Mathis.Marion@silabs.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
When accsssing /proc/self/exe from a userspace program, linux-user tries
to resolve the name via realpath(), which may fail if the process
changed the working directory in the meantime.
An example:
- a userspace program ist started with ./testprogram
- the program runs chdir("/tmp")
- then the program calls readlink("/proc/self/exe")
- linux-user tries to run realpath("./testprogram") which fails
because ./testprogram isn't in /tmp
- readlink() will return -ENOENT back to the program
Avoid this issue by resolving the full path name of the started process
at startup of linux-user and store it in real_exec_path[]. This then
simplifies the emulation of readlink() and readlinkat() as well, because
they can simply copy the path string to userspace.
I noticed this bug because the testsuite of the debian package "pandoc"
failed on linux-user while it succeeded on real hardware. The full log
is here:
https://buildd.debian.org/status/fetch.php?pkg=pandoc&arch=hppa&ver=2.17.1.1-1.1%2Bb1&stamp=1670153210&raw=0
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20221205113825.20615-1-deller@gmx.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
fork()ed processes currently start with
current_cpu->in_exclusive_context set, which is, strictly speaking, not
correct, but does not cause problems (even assertion failures).
With one of the next patches, the code begins to rely on this value, so
fix it by always calling end_exclusive() in fork_end().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230214140829.45392-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Applications do call sendmsg() without any IOV, e.g.:
sendmsg(4, {msg_name=NULL, msg_namelen=0, msg_iov=NULL, msg_iovlen=0,
msg_control=[{cmsg_len=36, cmsg_level=SOL_ALG, cmsg_type=0x2}],
msg_controllen=40, msg_flags=0}, MSG_MORE) = 0
sendmsg(4, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="The quick brown fox jumps over t"..., iov_len=183}],
msg_iovlen=1, msg_control=[{cmsg_len=20, cmsg_level=SOL_ALG, cmsg_type=0x3}],
msg_controllen=24, msg_flags=0}, 0) = 183
The function do_sendrecvmsg_locked() is used for sndmsg() and recvmsg()
and calls lock_iovec() to lock the IOV into memory. For the first
sendmsg() above it returns NULL and thus wrongly skips the call the host
sendmsg() syscall, which will break the calling application.
Fix this issue by:
- allowing sendmsg() even with empty IOV
- skip recvmsg() if IOV is NULL
- skip both if the return code of do_sendrecvmsg_locked() != 0, which
indicates some failure like EFAULT on the IOV
Tested with the debian "ell" package with hppa guest on x86_64 host.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20221212173416.90590-2-deller@gmx.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Denis Drakhnia
Helge Deller
Richard Henderson
Akihiko Odaki
Peter Maydell
Juan Quintela
Andreas Schwab
Pierrick Bouvier
Robbin Ehn
Ilya Leoshkevich
Michael Tokarev
Thomas Weißschuh
Afonso Bordado
Mathis Marion