strerror() is commonly used.
For example in kselftest which currently needs to do an #ifdef NOLIBC to
handle the lack of strerror().
Keep it simple and reuse the output format of perror() for strerror().
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
The implementation always works on uintmax_t values.
This is inefficient when only 32bit are needed.
However for all functions this only happens for strtol() on 32bit
platforms.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20240425-nolibc-strtol-v1-2-bfeef7846902@weissschuh.net
All supported kernels are assumed to use struct new_utsname.
This is validated in test_uname().
uname(2) can for example be used in ksft_min_kernel_version() from the
kernels selftest framework.
Link: https://lore.kernel.org/lkml/20240412123536.GA32444@redhat.com/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
The return code should always be strlen(src), and we should copy at most
size-1 bytes.
While we are there, make sure to null-terminate the dst buffer if we
copied something.
Signed-off-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
The return code should always be strlen(src) + strnlen(dst, size).
Let's make sure to copy at most size-1 bytes from src and null-terminate
the dst buffer if we did copied something.
While we can use strnlen() and strncpy() to implement strlcat(), this is
simple enough and results in shorter code when compiled.
Signed-off-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
As with commit 8d304a3740, "tools/nolibc/string: export memset() and
memmove()", gcc -Os without -ffreestanding may fail to compile with:
cc -fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib -lgcc -static -o test test.c
/usr/bin/ld: /tmp/cccIasKL.o: in function `main':
test.c:(.text.startup+0x1e): undefined reference to `strlen'
collect2: error: ld returned 1 exit status
As on the aforementioned commit, this patch adds a section to export
this function so compilation works on those cases too.
Signed-off-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Pass user_p_len to memcpy() instead of heap->len to prevent realloc()
from copying an extra sizeof(heap) bytes from beyond the allocated
region.
Signed-off-by: Brennan Xavier McManus <bxmcmanus@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Fixes: 0e0ff63840 ("tools/nolibc/stdlib: Implement `malloc()`, `calloc()`, `realloc()` and `free()`")
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
A future commit will include linux/resource.h, which will conflict with
the private definition of struct rusage in nolibc.
Avoid the conflict by dropping the private definition and use the one
from the UAPI headers.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/20231123-nolibc-rlimit-v1-1-a428b131de2a@weissschuh.net/
Acked-by: Willy Tarreau <w@1wt.eu>
__attribute__(format(printf)) can also be used for functions that take a
va_list argument.
As per the GCC docs:
For functions where the arguments are not available to be checked
(such as vprintf), specify the third parameter as zero.
Link: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
MIPS requires some extra instructions to set up the $gp register for the
with a pointer to the global data area.
This isn't needed for non-PIC builds, but this patch enables the code
unconditionally to prevent bitrot.
Also enable PIC in one of the test configurations for ongoing
validation.
Link: https://lore.kernel.org/r/20231108-nolibc-pic-v2-1-4fb0d6284757@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
When installing nolibc to a sysroot arch.h is not used so its ABI check
is bypassed. This makes is possible to compile nolibc with a non O32 ABI
which may build but can not run.
Move the check into arch-mips.h so it will always be evaluated.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
When an architecture is unsupported arch.h would silently continue.
This leads to a lot of followup errors because my_syscallX() is not
defined and the startup code is missing.
Avoid these confusing errors and fail the build early with a clear
error message and location.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Linux defines a few custom flags for waitpid() which aren't currently
provided by nolibc, make them available to nolibc based programs by just
including linux/wait.h where they are defined instead of defining our
own copy of the flags.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
All symbols created by nolibc are also visible to user code.
Syscall constants are expected to come from the kernel headers and
should not be made up by nolibc.
Refactor the logic to avoid defining syscall numbers.
Also the new code is easier to understand.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20230917-nolibc-syscall-nr-v2-3-03863d509b9a@weissschuh.net
This function is only called by memcpy(), there is no real reason to
have this wrapper. Delete this function and move the code to memcpy()
directly.
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Reviewed-by: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
This nolibc internal function is not used. Delete it. It was probably
supposed to handle memmove(), but today the memmove() has its own
implementation.
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Reviewed-by: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
This allows nolic to work with `-nostdinc` avoiding any reliance on
system headers.
The implementation has been lifted from musl libc 1.2.4.
There is already an implementation of stdarg.h in include/linux/stdarg.h
but that is GPL licensed and therefore not suitable for nolibc.
The used compiler builtins have been validated to be at least available
since GCC 4.1.2 and clang 3.0.0.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
The ABI mandates that the %esp register must be a multiple of 16 when
executing a 'call' instruction.
Commit 2ab446336b ("tools/nolibc: i386: shrink _start with _start_c")
simplified the _start function, but it didn't take care of the %esp
alignment, causing SIGSEGV on SSE and AVX programs that use aligned move
instruction (e.g., movdqa, movaps, and vmovdqa).
The 'and $-16, %esp' aligns the %esp at a multiple of 16. Then 'push
%eax' will subtract the %esp by 4; thus, it breaks the 16-byte
alignment. Make sure the %esp is correctly aligned after the push by
subtracting 12 before the push.
Extra:
Add 'add $12, %esp' before the 'and $-16, %esp' to avoid over-estimating
for particular cases as suggested by Willy.
A test program to validate the %esp alignment on _start can be found at:
https://lore.kernel.org/lkml/ZOoindMFj1UKqo+s@biznet-home.integral.gnuweeb.org
[ Thomas: trim Fixes tag commit id ]
Cc: Zhangjin Wu <falcon@tinylab.org>
Fixes: 2ab446336b ("tools/nolibc: i386: shrink _start with _start_c")
Reported-by: Nicholas Rosenberg <inori@vnlx.org>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Reviewed-by: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Having __sysret() as an inline function has the unfortunate effect of
adding casts and large constants comparisons after the syscall returns
that significantly inflate some light code that's otherwise syscall-
heavy. Even nolibc-test grew by ~1%.
Let's switch back to a macro for this, and use it only with signed
arguments. Note that it is also possible to design a slightly more
complex macro covering unsigned and pointers but we only have 3 such
syscalls so it is pointless, and these were just addressed not to use
this macro anymore. Now for the argument (the local variable containing
the syscall return value), any negative value is an error, that results
in -1 being returned and errno to be assigned the opposite value.
This may be revisited again in the future if really needed but for now
let's get back to something sane.
Fixes: 428905da6e ("tools/nolibc: sys.h: add a syscall return helper")
Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/
Link: https://lore.kernel.org/lkml/ZNKOJY+g66nkIyvv@1wt.eu/
Cc: Zhangjin Wu <falcon@tinylab.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Thomas Weißschuh <thomas@t-8ch.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
The __sysret() function causes some undesirable casts so we'll revert
it. In order to keep it simple it will now only support integer return
values like in the past, so we must basically revert the changes that
were made to these 3 syscalls which return a pointer so that they
simply rely on their own test and the SET_ERRNO() macro.
Fixes: 4201cfce15 ("tools/nolibc: clean up sbrk() routine")
Fixes: 924e9539ae ("tools/nolibc: clean up mmap() routine")
Fixes: d27447bc2e ("tools/nolibc: sys.h: apply __sysret() helper")
Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/
Link: https://lore.kernel.org/lkml/ZNKOJY+g66nkIyvv@1wt.eu/
Cc: Zhangjin Wu <falcon@tinylab.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Thomas Weißschuh <thomas@t-8ch.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Silence the following warnings reported by the new -Wall -Wextra options
with pure assembly code.
In file included from sysroot/powerpc/include/stdio.h:13,
from nolibc-test.c:13:
sysroot/powerpc/include/arch.h: In function '_start':
sysroot/powerpc/include/arch.h:192:32: warning: unused variable 'r2' [-Wunused-variable]
192 | register volatile long r2 __asm__ ("r2") = (void *)&TOC - (void *)_start;
| ^~
sysroot/powerpc/include/arch.h:187:97: warning: optimization may eliminate reads and/or writes to register variables [-Wvolatile-register-var]
187 | void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
| ^~~~~~
Since only elfv2 ABI requires to save the TOC/GOT pointer to r2
register, when using elfv1 ABI, the old C code is simply ignored by the
compiler, but the compiler can not ignore the inline assembly code and
will introduce build failure or running segfaults. So, let's further
only add the new assembly code for elfv2 ABI with the checking of
_CALL_ELF == 2.
Link: https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.pdf
Link: https://www.llvm.org/devmtg/2014-04/PDFs/Talks/Euro-LLVM-2014-Weigand.pdf
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This allows to generate smaller text/data/dec size.
As the _start_c() function added by crt.h, __stack_chk_init() is called
from _start_c() instead of the assembly _start. So, it is able to mark
it with static now.
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This follows the 64-bit PowerPC ABI [1], refers to the slides: "A new
ABI for little-endian PowerPC64 Design & Implementation" [2] and the
musl code in arch/powerpc64/crt_arch.h.
First, stdu and clrrdi are used instead of stwu and clrrwi for
powerpc64.
Second, the stack frame size is increased to 32 bytes for powerpc64, 32
bytes is the minimal stack frame size supported described in [2].
Besides, the TOC pointer (GOT pointer) must be saved to r2.
This works on both little endian and big endian 64-bit PowerPC.
[1]: https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.pdf
[2]: https://www.llvm.org/devmtg/2014-04/PDFs/Talks/Euro-LLVM-2014-Weigand.pdf
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Both syscall declarations and _start code definition are added for
powerpc to nolibc.
Like mips, powerpc uses a register (exactly, the summary overflow bit)
to record the error occurred, and uses another register to return the
value [1]. So, the return value of every syscall declaration must be
normalized to match the __sysret() helper, return -value when there is
an error, otheriwse, return value directly.
Glibc and musl use different methods to check the summary overflow bit,
glibc (sysdeps/unix/sysv/linux/powerpc/sysdep.h) saves the cr register
to r0 at first, and then check the summary overflow bit in cr0:
mfcr r0
r0 & (1 << 28) ? -r3 : r3
-->
10003c14: 7c 00 00 26 mfcr r0
10003c18: 74 09 10 00 andis. r9,r0,4096
10003c1c: 41 82 00 08 beq 0x10003c24
10003c20: 7c 63 00 d0 neg r3,r3
Musl (arch/powerpc/syscall_arch.h) directly checks the summary overflow
bit with the 'bns' instruction, it is smaller:
/* no summary overflow bit means no error, return value directly */
bns+ 1f
/* otherwise, return negated value */
neg r3, r3
1:
-->
10000418: 40 a3 00 08 bns 0x10000420
1000041c: 7c 63 00 d0 neg r3,r3
Like musl, Linux (arch/powerpc/include/asm/vdso/gettimeofday.h) uses the
same method for do_syscall_2() too.
Here applies the second method to get smaller size.
[1]: https://man7.org/linux/man-pages/man2/syscall.2.html
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Otherwise both gcc and clang may generate warnings about type
mismatches:
sysroot/mips/include/string.h:12:14: warning: mismatch in argument 1 type of built-in function 'malloc'; expected 'unsigned int' [-Wbuiltin-declaration-mismatch]
12 | static void *malloc(size_t len);
| ^~~~~~
The compiler provides __SIZE_TYPE__ as the type that corresponds to size_t
(typically "long unsigned int" or "unsigned int"). It was verified to be
available at least since gcc-3.4 and clang-3.8, so from now on we'll use
this definition for size_t.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/20230805161929.GA15284@1wt.eu/
Signed-off-by: Willy Tarreau <w@1wt.eu>
getauxval() returns an unsigned long but the overall type of the ternary
operator needs to be signed.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This warning will be enabled later so avoid triggering it.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
It's documented as returning int which is also implemented by glibc and
musl, so adopt that return type.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
According to manual page [1], posix spec [2] and source code like
arch/mips/kernel/syscall.c, for historic reasons, the sys_pipe() syscall
on some architectures has an unusual calling convention. It returns
results in two registers which means there is no need for it to do
verify the validity of a userspace pointer argument. Historically that
used to be expensive in Linux. These days the performance advantage is
negligible.
Nolibc doesn't support the unusual calling convention above, luckily
Linux provides a generic sys_pipe2() with an additional flags argument
from 2.6.27. If flags is 0, then pipe2() is the same as pipe(). So here
we use sys_pipe2() to implement the pipe().
pipe2() is also provided to allow users to use flags argument on demand.
[1]: https://man7.org/linux/man-pages/man2/pipe.2.html
[2]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/pipe.html
Suggested-by: Zhangjin Wu <falcon@tinylab.org>
Link: https://lore.kernel.org/all/20230729100401.GA4577@1wt.eu/
Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Add a minimal implementation of setvbuf(), which error checks the mode
argument (as required by spec) and returns. Since nolibc never buffers
output, nothing needs to be done.
The kselftest framework recently added a call to setvbuf(). As a result,
any tests that use the kselftest framework and nolibc cause a compiler
error due to missing function. This provides an urgent fix for the
problem which is preventing arm64 testing on linux-next.
Example:
clang --target=aarch64-linux-gnu -fintegrated-as
-Werror=unknown-warning-option -Werror=ignored-optimization-argument
-Werror=option-ignored -Werror=unused-command-line-argument
--target=aarch64-linux-gnu -fintegrated-as
-fno-asynchronous-unwind-tables -fno-ident -s -Os -nostdlib \
-include ../../../../include/nolibc/nolibc.h -I../..\
-static -ffreestanding -Wall za-fork.c
build/kselftest/arm64/fp/za-fork-asm.o
-o build/kselftest/arm64/fp/za-fork
In file included from <built-in>:1:
In file included from ./../../../../include/nolibc/nolibc.h:97:
In file included from ./../../../../include/nolibc/arch.h:25:
./../../../../include/nolibc/arch-aarch64.h:178:35: warning: unknown
attribute 'optimize' ignored [-Wunknown-attributes]
void __attribute__((weak,noreturn,optimize("omit-frame-pointer")))
__no_stack_protector _start(void)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from za-fork.c:12:
../../kselftest.h:123:2: error: call to undeclared function 'setvbuf';
ISO C99 and later do not support implicit function declarations
[-Wimplicit-function-declaration]
setvbuf(stdout, NULL, _IOLBF, 0);
^
../../kselftest.h:123:24: error: use of undeclared identifier '_IOLBF'
setvbuf(stdout, NULL, _IOLBF, 0);
^
1 warning and 2 errors generated.
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Link: https://lore.kernel.org/linux-kselftest/CA+G9fYus3Z8r2cg3zLv8uH8MRrzLFVWdnor02SNr=rCz+_WGVg@mail.gmail.com/
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Also clean up the instructions in delayed slots.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
move most of the _start operations to _start_c(), include the
stackprotector initialization.
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
As suggested by Thomas, It is able to move the stackprotector
initialization from the assembly _start to the beginning of the new
_start_c(). Let's call __stack_chk_init() in _start_c() as a
preparation.
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/lkml/a00284a6-54b1-498c-92aa-44997fa78403@t-8ch.de/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Let's define an empty __stack_chk_init for the !_NOLIBC_STACKPROTECTOR
branch.
This allows to remove #ifdef around every call of __stack_chk_init().
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
