TB compile flags, tb_page_addr_t type, tb_cflags() and few
other methods are defined in "exec/translation-block.h".
All these files don't include "exec/translation-block.h" but
include "exec/exec-all.h" which include it. Explicitly include
"exec/translation-block.h" to be able to remove it from
"exec/exec-all.h" later when it won't be necessary. Otherwise
we'd get errors such:
accel/tcg/internal-target.h:59:20: error: a parameter list without types is only allowed in a function definition
59 | void tb_lock_page0(tb_page_addr_t);
| ^
accel/tcg/tb-hash.h:64:23: error: unknown type name 'tb_page_addr_t'
64 | uint32_t tb_hash_func(tb_page_addr_t phys_pc, vaddr pc,
| ^
accel/tcg/tcg-accel-ops.c:62:36: error: use of undeclared identifier 'CF_CLUSTER_SHIFT'
62 | cflags = cpu->cluster_index << CF_CLUSTER_SHIFT;
| ^
accel/tcg/watchpoint.c:102:47: error: use of undeclared identifier 'CF_NOIRQ'
102 | cpu->cflags_next_tb = 1 | CF_NOIRQ | curr_cflags(cpu);
| ^
target/i386/helper.c:536:28: error: use of undeclared identifier 'CF_PCREL'
536 | if (tcg_cflags_has(cs, CF_PCREL)) {
| ^
target/rx/cpu.c:51:21: error: incomplete definition of type 'struct TranslationBlock'
51 | cpu->env.pc = tb->pc;
| ~~^
system/physmem.c:2977:9: error: call to undeclared function 'tb_invalidate_phys_range'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
2977 | tb_invalidate_phys_range(addr, addr + length - 1);
| ^
plugins/api.c:96:12: error: call to undeclared function 'tb_cflags'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
96 | return tb_cflags(tcg_ctx->gen_tb) & CF_MEMI_ONLY;
| ^
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241114011310.3615-5-philmd@linaro.org>
The TranslationBlock flags are defined in 'exec/translation-block.h'.
tcg_cflags_has/set() use them, it is more logical to declare them in
the same place. Move them there too.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212144430.66224-2-philmd@linaro.org>
Move various declarations related to user emulation
from "exec/exec-all.h" to "user/cpu_loop.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-19-philmd@linaro.org>
Declare cpu_loop() once in "user/cpu_loop.h".
bsd-user gets the G_NORETURN attribute.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-18-philmd@linaro.org>
"linux-user/cpu_loop-common.h" is generic enough to be used by
bsd-user, so rename it as "user/cpu_loop.h".
Mechanical change running:
$ sed -i -e 's,cpu_loop-common.h,user/cpu_loop.h,' \
$(git grep -l cpu_loop-common.h)
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-17-philmd@linaro.org>
Move declarations related to page protection under user
emulation from "exec/cpu-all.h" to "user/page-protection.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-15-philmd@linaro.org>
Move declarations related to page protection under user
emulation from "exec/cpu-all.h" to "user/page-protection.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-14-philmd@linaro.org>
Move declarations related to page protection under user
emulation from "exec/cpu-all.h" to "user/page-protection.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-12-philmd@linaro.org>
Move mmap_lock(), mmap_unlock() declarations and the
WITH_MMAP_LOCK_GUARD() definition to 'exec/page-protection.h'.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-5-philmd@linaro.org>
arm_set_mte_tcf0() uses the abi_long type which is defined
in "user/abitypes.h". Include it in order to avoid when
refactoring:
In file included from ../../target/arm/gdbstub64.c:28:
../linux-user/aarch64/mte_user_helper.h:30:42: error: unknown type name ‘abi_long’; did you mean ‘u_long’?
30 | void arm_set_mte_tcf0(CPUArchState *env, abi_long value);
| ^~~~~~~~
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-3-philmd@linaro.org>
The values previously used for "HEX_EXCP_*" were the cause code
definitions and not the event numbers. So in this commit, we update
the names to reflect the cause codes. In HEX_EVENT_TRAP0's case, we add
a new "HEX_EVENT_*" with the correct event number.
Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>
Set the default NaN pattern explicitly for the arm target.
This includes setting it for the old linux-user nwfpe emulation.
For nwfpe, our default doesn't match the real kernel, but we
avoid making a behaviour change in this commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241202131347.498124-41-peter.maydell@linaro.org
print_mmap() assumes that mmap() receives arguments via memory if
mmap2() is present. s390x (as opposed to s390) does not fit this
pattern: it does not have mmap2(), but mmap() still receives arguments
via memory.
Fix by sharing the detection logic between syscall.c and strace.c.
Cc: qemu-stable@nongnu.org
Fixes: d971040c2d ("linux-user: Fix strace output for old_mmap")
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20241120212717.246186-1-iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This aligns with strace, and is very useful when tracing multi-threaded
programs. The result is the same in single-threaded programs.
Signed-off-by: J. Neuschäfer <j.neuschaefer@gmx.net>
Message-Id: 20241024-strace-v1-1-56c4161431cd@gmx.net
[rth: Use TaskState.ts_tid via get_task_state()]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In be8 mode, instructions are little-endian.
In be32 mode, instructions are big-endian.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2333
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reduce vdso alignment to minimum page size.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reduce vdso alignment to minimum page size.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reduce vdso alignment to minimum page size.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reduce vdso alignment to minimum page size.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This field is write-only. Use only the function-local
variable within load_elf_image.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Most binaries don't actually depend on more than page alignment,
but any binary can request it. Not honoring this was a bug.
This became obvious when gdb reported
Failed to read a valid object file image from memory
when examining some vdso which are marked as needing more
than page alignment.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Running qemu-i386 on a system running with SELinux in enforcing mode
(more precisely: s390x trixie container on Fedora 40) fails with:
qemu-i386: tests/tcg/i386-linux-user/sigreturn-sigmask: Unable to find a guest_base to satisfy all guest address mapping requirements
00000000-ffffffff
The reason is that main() determines mmap_min_addr from
/proc/sys/vm/mmap_min_addr, but SELinux additionally defines
CONFIG_LSM_MMAP_MIN_ADDR, which is normally larger: 32K or 64K, but,
in general, can be anything. There is no portable way to query its
value: /boot/config, /proc/config and /proc/config.gz are distro- and
environment-specific.
Once the identity map fails, the magnitude of guest_base does not
matter, so fix by starting the search from 1M or 1G.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2598
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20241023002558.34589-1-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The commit fd6f7798ac ("linux-user: Use direct syscalls for setuid(),
etc") added direct syscall wrappers for setuid(), setgid(), etc since the
system calls have different semantics than the libc functions.
Add and use the corresponding wrappers for setreuid and setregid which
were missed in that commit.
This fixes the build of the debian package of the uid_wrapper library
(https://cwrap.org/uid_wrapper.html) when running linux-user.
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <Zyo2jMKqq8hG8Pkz@p100>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Some applications want to use low priority realtime signals (e.g.,
SIGRTMAX). Currently QEMU cannot map all target realtime signals to
host realtime signals, and chooses to sacrifice the end of the target
realtime signal range.
Allow users to choose how to map target realtime signals to host
realtime signals using the new -t option, the new QEMU_RTSIG_MAP
environment variable, and the new -Drtsig_map=\"...\" meson flag.
To simplify things, the meson flag is not per-target, because the
intended use case is app-specific qemu-user builds.
The mapping is specified using the "tsig hsig count[,...]" syntax.
Target realtime signals [tsig,tsig+count) are mapped to host realtime
signals [hsig,hsig+count). Care is taken to avoid double and
out-of-range mappings.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20241029232211.206766-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When debugging qemu-user processes using gdbstub, the following warning
appears every time:
warning: BFD: warning: system-supplied DSO at 0x7f8253cc3000 has a corrupt string table index
The reason is that QEMU does not map the VDSO's section headers. The
VDSO's ELF header's e_shoff points to zeros, which GDB fails to parse.
The difference with the kernel's VDSO is that the latter is mapped as a
blob, ignoring program headers - which also don't cover the section
table. QEMU, on the other hand, loads it as an ELF file.
There appears to be no way to place section headers inside a section,
and, therefore, no way to refer to them from a linker script. Also, ld
hardcodes section headers to be non-loadable, see
_bfd_elf_assign_file_positions_for_non_load(). In theory ld could be
enhanced by implementing an "SHDRS" keyword in addition to the existing
"FILEHDR" and "PHDRS".
There are multiple ways to resolve the issue:
- Copy VDSO as a blob in load_elf_vdso(). This would require creating
specialized loader logic, that duplicates parts of load_elf_image().
- Fix up VDSO's PHDR size in load_elf_vdso(). This would require either
duplicating the parsing logic, or adding an ugly parameter to
load_elf_image().
- Fix up VDSO's PHDR size in gen-vdso. This is the simplest solution,
so do it.
There are two tricky parts:
- Byte-swaps need to be done either on local copies, or in-place and
then reverted in the end. To preserve the existing code structure, do
the former for Sym and Dyn, and the latter for Ehdr, Phdr, and Shdr.
- There must be no .bss, which is already the case - but having an
explicit check is helpful to ensure correctness.
To verify this change, I diffed the on-disk and the loaded VDSOs; the
result does not show anything unusual, except for what seems to be an
existing oversight (which should probably be fixed separately):
│ Symbol table '.dynsym' contains 8 entries:
│ Num: Value Size Type Bind Vis Ndx Name
│ - 0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
│ - 6: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.29
│ + 0: 00007f61075bf000 0 NOTYPE LOCAL DEFAULT UND
│ + 6: 00007f61075bf000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.29
Fixes: 2fa536d107 ("linux-user: Add gen-vdso tool")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20241023202850.55211-1-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Set the 2-NaN propagation rule explicitly in the float_status words
we use. We wrap this plus the pre-existing setting of the
tininess-before-rounding flag in a new function
arm_set_default_fp_behaviours() to avoid repetition, since we have a
lot of float_status words at this point.
The situation with FPA11 emulation in linux-user is a little odd, and
arguably "correct" behaviour there would be to exactly match a real
Linux kernel's FPA11 emulation. However FPA11 emulation is
essentially dead at this point and so it seems better to continue
with QEMU's current behaviour and leave a comment describing the
situation.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-4-peter.maydell@linaro.org
Current definition yields a negative 32bits value, messing up hwprobe
result when Zvfhmin extension presents. Replace it by using a 1ULL bit
shift value as done in kernel upstream.
Link: 5ea6764d90
Fixes: a3432cf227 ("linux-user/riscv: Sync hwprobe keys with Linux")
Cc: qemu-stable@nongnu.org
Signed-off-by: Yao Zi <ziyao@disroot.org>
Message-ID: <20241022160136.21714-2-ziyao@disroot.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit 9651cead2f ("linux-user: add openat2 support in linux-user")
ships a definition of struct open_how_ver0 while assuming type __u64 is
available in code, which is not the case when building QEMU on musl.
Let's replaces __u64 with uint64_t.
Fixes: 9651cead2f ("linux-user: add openat2 support in linux-user")
Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20241022122929.17465-2-ziyao@disroot.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add a function for formatting target sigsets. It can be useful for
other syscalls in the future, so put it into the beginning of strace.c.
For simplicity, do not implement the strace's ~[] output syntax.
Add a rt_sigprocmask return handler.
Example outputs:
753914 rt_sigprocmask(SIG_BLOCK,[SIGCHLD SIGTSTP SIGTTIN SIGTTOU],0x00007f80fddfe380,8) = 0 (oldset=[SIGTTOU])
753914 rt_sigprocmask(SIG_SETMASK,[SIGCHLD],NULL,8) = 0
753914 rt_sigprocmask(SIG_BLOCK,NULL,0x00007f80fddff3c0,8) = 0 (oldset=[])
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20241022102726.18520-1-iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
do_setcontext() copies the target sigmask without endianness handling
and then uses target_to_host_sigset_internal(), which expects a
byte-swapped one. Use target_to_host_sigset() instead.
Fixes: bcd4933a23 ("linux-user: ppc signal handling")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20241017125811.447961-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If one thread modifies the mappings and another thread prints them,
a situation may occur that the printer thread sees a guest mapping
without a corresponding host mapping, leading to a crash in
open_self_maps_2().
Cc: qemu-stable@nongnu.org
Fixes: 7b7a3366e1 ("linux-user: Use walk_memory_regions for open_self_maps")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20241014203441.387560-1-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Clean up unused (already commented-out) header from syscall.c.
Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The x86 architecture uses little endianness. Directly use
the little-endian LD/ST API.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20241003234211.53644-4-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Since commit 95b9c27c81 ("linux-user: Remove unused handle_vm86_fault")
a bunch of other "static inline" function are now unused, too. Clang
warns about such unused "static inline" functions in .c files, so the
build currently breaks when compiling with "--enable-werror". Remove
the unused functions to get it going again.
Fixes: 95b9c27c81 ("linux-user: Remove unused handle_vm86_fault")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Message-ID: <20241011161845.417342-1-thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The kernel uses orig_rax/orig_eax to store the syscall number before
a syscall. One can see this value in core dumps and ptrace.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20240912093012.402366-3-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
It's the same as env_cpu(), but for const objects.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20240912093012.402366-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240807124306.52903-6-philmd@linaro.org>
[rth: Do not dump output buffers.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Rather than 'raw param', display as pointer to get
"NULL" instead of "0x00000000".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20240807124306.52903-3-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When the %addr argument can not be accessed, a double comma
is logged (the final qemu_log call prepend a comma). Move
the comma from the final qemu_log to the preceeding switch
cases that had omitted it.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20240807124306.52903-2-philmd@linaro.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
[rth: Move comma into the various switch cases.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Borrow the code for formatting the most frequent WIFEXITED() and
WIFSIGNALED() special cases from from the strace's printstatus().
Output examples:
474729 wait4(-1,0x7f00767ff0a0,0,(nil)) = 474733 (wstatus={WIFEXITED(s) && WEXITSTATUS(s) == 1})
475833 wait4(-1,0x7f7de61ff0a0,0,(nil)) = 475837 (wstatus={WIFSIGNALED(s) && WTERMSIG(s) == SIGKILL})
1168 waitpid(1171,0x7f44eea00340,0) = 1171 (wstatus={WIFSIGNALED(s) && WTERMSIG(s) == SIGKILL})
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20241001193244.14939-1-iii@linux.ibm.com>
[rth: Drop extra output for NULL wstatus or error reading.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit adds support for the `openat2()` to `QEMU_STRACE`. It
will use the `openat2.h` header if available to create user
readable flags for the `resolve` argument but does not require
the header otherwise.
It also makes `copy_struct_from_user()` available via `qemu.h`
and `open_how_ver0` via `syscall_defs.h` so that strace.c can use
them.
Signed-off-by: Michael Vogt <mvogt@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <f02d40c7751c03af885ced6dd94e4734d4be4d8f.1727795334.git.mvogt@redhat.com>
[rth: Add braces around the expanded how structure, like strace(3)]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit adds support for the `openat2()` syscall in the
`linux-user` userspace emulator.
It is implemented by extracting a new helper `maybe_do_fake_open()`
out of the exiting `do_guest_openat()` and share that with the
new `do_guest_openat2()`. Unfortunately we cannot just make
do_guest_openat2() a superset of do_guest_openat() because the
openat2() syscall is stricter with the argument checking and
will return an error for invalid flags or mode combinations (which
open()/openat() will ignore).
The implementation is similar to SYSCALL_DEFINE(openat2), i.e.
a new `copy_struct_from_user()` is used that works the same
as the kernels version to support backwards-compatibility
for struct syscall argument.
Instead of including openat2.h we create a copy of `open_how`
as `open_how_ver0` to ensure that if the structure grows we
can log a LOG_UNIMP warning.
Note that in this commit using openat2() for a "faked" file in
/proc will honor the "resolve" flags for
RESOLVE_NO_{MAGIC,SYM}LINKS for path based access to /proc/self/exe
(which is the only magic link we support for faked files).
Note it will not catch special access via e.g. dirfd. This is not
great but it seems similar to the exiting behavior when openat()
is called with a dirfd to "/proc". Here too the fake file lookup
may not catch the special file because no dirfd is used to
determine if the path is in /proc.
Signed-off-by: Michael Vogt <mvogt@redhat.com>
Buglink: https://github.com/osbuild/bootc-image-builder/issues/619
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <1c2c8c9db3731ed4c6fd9b10c63637c3e4caf8f5.1727795334.git.mvogt@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Comparing a string of 4 bytes only works in little-endian.
Adjust bulk bswap to only apply to the note payload.
Perform swapping of the note header manually; the magic
is defined so that it does not need a runtime swap.
Fixes: 83f990eb5a ("linux-user/elfload: Parse NT_GNU_PROPERTY_TYPE_0 notes")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2596
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
