May 2016 - devel - example.com

uClibc-ng and uClibc memset bug, ARM
by Lucian Cojocar 26 Jun '16

26 Jun '16

Hi all, in libc/string/arm/memset.S[0]. If the code is compiled with #undef __thumb2__ and with #undef THUMB1_ONLY (this seems to be case for Tomato[1] at least and for buildroot) then the code looks like this[2]: """ memset: mov a4, a1 cmp a3, $8 @ at least 8 bytes to do? blt 2f orr a2, a2, a2, lsl $8 orr a2, a2, a2, lsl $16 ... 2: movs a3, a3 @ anything left? IT(t, eq) BXC(eq, lr) @ nope rsb a3, a3, $7 add pc, pc, a3, lsl $2 <--- a3 can be larger than $7 here mov r0, r0 strb a2, [a4], $1 strb a2, [a4], $1 ... """" The problem is that the 'BLT' instruction checks for *signed* values. So if a3, length parameter of memset, is negative, then value added to the PC will be large. In short, an attacker gains control of PC through the len parameter of memset. The attack is a bit unrealistic, as it requires that the application that uses uClibc allows a user to control a memory chunk larger than 2GB. I only tested this on qemu-system-arm[3]. The code was just calling memset(buf, 0xaa, 0xffff0000), memset, in this example[3] is @0x1003c. This bug is similar to CVE-2011-2702[4, 5]. Probably we should notify oss-security and get a CVE for this as the impact is unknown. Thanks, Lucian [0]https://github.com/wbx-github/uclibc-ng/blob/master/libc/string/arm/memse… [1]http://tomato.groov.pl/download/K26ARM/132/tomato-R7000-ARM--132-AIO-64K.zip [2]disas.S (attached) [3]qemu.log (attached) [4]http://www.cvedetails.com/cve/CVE-2011-2702/ [5]http://old.sebug.net/paper/Exploits-Archives/2012-exploits/1208-exploits/…

4 10

static linking ppc
by Waldemar Brodkorb 26 Jun '16

26 Jun '16

Hi Leonid, you recently fixed a bug somehow related to static linking stuff. Do you have an idea why compiling for PowerPC fails like this when using static linking: /home/wbx/ppc-static/toolchain_qemu-ppc-macppc_uclibc-ng_hard/usr/bin/ppc-openadk-linux-uclibc-gcc -Wl,-EB -Wl,-z,now -Wl,-static -static-libgcc -Wl,-rpath,/home/wbx/ppc-static/toolchain_build_qemu-ppc-macppc_uclibc-ng_hard/w-uClibc-ng-1.0.15-1/uClibc-ng-1.0.15/test/argp -L/home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/lib -L/home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib -Wl,-O1 -Wl,-rpath -Wl,/usr/lib -Wl,-rpath-link -Wl,/home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib -static bug-argp1.o -o bug-argp1 -luargp /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libc.a(sigsetops.os): In function `__GI___sigismember': sigsetops.c:(.text+0x0): multiple definition of `__sigismember' /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libuargp.a(argp-xinl.os):argp-xinl.c:(.text+0x0): first defined here /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libc.a(sigsetops.os): In function `__GI___sigaddset': sigsetops.c:(.text+0x28): multiple definition of `__sigaddset' /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libuargp.a(argp-xinl.os):argp-xinl.c:(.text+0x28): first defined here /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libc.a(sigsetops.os): In function `__GI___sigdelset': sigsetops.c:(.text+0x4c): multiple definition of `__sigdelset' /home/wbx/ppc-static/target_qemu-ppc-macppc_uclibc-ng_hard/usr/lib/libuargp.a(argp-xinl.os):argp-xinl.c:(.text+0x4c): first defined here collect2: error: ld returned 1 exit status make[8]: *** [bug-argp1] Error 1 make[7]: *** [_dircompile_argp] Error 2 make[6]: *** [test_compile] Error 2 make[5]: *** [/home/wbx/ppc-static/toolchain_build_qemu-ppc-macppc_uclibc-ng_hard/w-uClibc-ng-1.0.15-1/uClibc-ng-1.0.15/.installed] Error 2 make[4]: *** [uclibc-ng-install] Error 2 make[3]: *** [toolchain/final] Error 2 make[2]: *** [world] Error 2 ARM and MIPS works fine. best regards Waldemar

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Re: [uclibc-ng-devel] Patchwork instance for uClibc-ng
by Alexey Brodkin 16 Jun '16

16 Jun '16

Hi Waldemar, 21 мая 2016 г. 11:39 пользователь Peter Korsgaard <peter(a)korsgaard.com> написал: > > >>>>> "Waldemar" == Waldemar Brodkorb <wbx(a)uclibc-ng.org> writes: > > Hi, > > >> It should be pretty simple - we did this for "linux-arc" recently. > > > So how would I register the project? > > I haven't seen a description how to do it on their website. > > I think you can just email Jeremy Kerr (jk(a)ozlabs.org) who maintains the > patchwork instance on ozlabs. Indeed, that's what we did back in the day. -Alexey

2 5

[ARM] unnecessary busy loop in __lll_timedlock_wait
by Leonid Lisovskiy 12 Jun '16

12 Jun '16

Hi, I'm propose to take a glibc's commit 6d96f5e4c0 to solve the unnecessary busy loop in __lll_timedlock_wait on ARM, described in details at: https://sourceware.org/bugzilla/show_bug.cgi?id=15119 https://patchwork.ozlabs.org/patch/332656/ what is your opinion? Regards, Leonid

2 11

[PATCH] [v3] linuxthreads.old: Fix segfault when pthread_mutex_unlock() called against unlocked NORMAL mutex.
by Leonid Lisovskiy 02 Jun '16

02 Jun '16

Althought, it is undefined behavior, there is no reason for segfault. Program received signal SIGSEGV, Segmentation fault. __pthread_unlock (lock=lock@entry=0x804b03c <lock+16>) at libpthread/linuxthreads.old/spinlock.c:231 231 (&lock->__status, oldstatus, (long)(thr->p_nextlock) & ~1L)) It occurs only on platforms which has HAS_COMPARE_AND_SWAP defined. Restore glibc commit fbaf6e72d6 "spinlock.c (__pthread_unlock): Don't crash if called for an untaken mutex." behavior, broken later by commit 4ad1d0cfbf. Signed-off-by: Leonid Lisovskiy <lly.dev(a)gmail.com> --- libpthread/linuxthreads/spinlock.c | 12 ++++++-- test/pthread/ex8-mtx-odd.c | 56 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+), 3 deletions(-) create mode 100644 test/pthread/ex8-mtx-odd.c diff --git a/libpthread/linuxthreads/spinlock.c b/libpthread/linuxthreads/spinlock.c index 80aeda5..ce97002 100644 --- a/libpthread/linuxthreads/spinlock.c +++ b/libpthread/linuxthreads/spinlock.c @@ -188,10 +188,16 @@ int __pthread_unlock(struct _pthread_fastlock * lock) WRITE_MEMORY_BARRIER(); again: - while ((oldstatus = lock->__status) == 1) { - if (__compare_and_swap_with_release_semantics(&lock->__status, + oldstatus = lock->__status; + if (oldstatus == 0 || oldstatus == 1) { + /* No threads are waiting for this lock. Please note that we also + enter this case if the lock is not taken at all. If this wouldn't + be done here we would crash further down. */ + if (! __compare_and_swap_with_release_semantics(&lock->__status, oldstatus, 0)) - return 0; + goto again; + + return 0; } /* Find thread in waiting queue with maximal priority */ diff --git a/test/pthread/ex8-mtx-odd.c b/test/pthread/ex8-mtx-odd.c new file mode 100644 index 0000000..791b2c2 --- /dev/null +++ b/test/pthread/ex8-mtx-odd.c @@ -0,0 +1,56 @@ +/* Copyright (C) 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper(a)redhat.com>, 2002. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <errno.h> +#include <pthread.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> + + +static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER; + +static int +do_test (void) +{ + + if (pthread_mutex_lock (&lock) != 0) + { + puts ("mutex_lock failed"); + exit (1); + } + + if (pthread_mutex_unlock (&lock) != 0) + { + puts ("1st mutex_unlock failed"); + exit (1); + } + + if (pthread_mutex_unlock (&lock) != 0) + { + puts ("2nd mutex_unlock failed"); + exit (1); + } + + return 0; +} + +#define TEST_FUNCTION do_test () +#include "../test-skeleton.c" -- 1.8.5.6

2 1

[PATCH] tests: Take in account Makefiles that have meaning for rebuild only.
by Leonid Lisovskiy 02 Jun '16

02 Jun '16

Currently, targets dependancy list don't include Makefile.in, this leads to incomplete rebuild after target's compiler/linker flags was changed. Use "$(wildcard)" function due to Makefile.in could be absent in subdirectory. Signed-off-by: Leonid Lisovskiy <lly.dev(a)gmail.com> --- test/Test.mak | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/test/Test.mak b/test/Test.mak index c1b34a7..c9b1f5a 100644 --- a/test/Test.mak +++ b/test/Test.mak @@ -116,7 +116,7 @@ compile: $(COMPILE_TARGETS) G_TARGET_SRCS := $(addsuffix .c,$(G_TARGETS)) U_TARGET_SRCS := $(addsuffix .c,$(U_TARGETS)) -MAKE_SRCS := Makefile $(TESTDIR)Makefile $(TESTDIR)Rules.mak $(TESTDIR)Test.mak +MAKE_SRCS := $(wildcard Makefile.in) $(TESTDIR)Makefile $(TESTDIR)Rules.mak $(TESTDIR)Test.mak $(U_TARGETS): $(U_TARGET_SRCS) $(MAKE_SRCS) $(showlink) -- 1.8.5.6

2 1

[PATCH] ldso/ARC: fix DT_RELACOUNT handling
by Vineet Gupta 01 Jun '16

01 Jun '16

From: Cupertino Miranda <cmiranda(a)synopsys.com> Wih new bintuils supporting DT_RELACOUNT, ldso was crashing as it was parsing relocs incorrectly. Apparently that code ran for first time and was never tested. Signed-off-by: Vineet Gupta <vgupta(a)synopsys.com> --- ldso/ldso/arc/dl-sysdep.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ldso/ldso/arc/dl-sysdep.h b/ldso/ldso/arc/dl-sysdep.h index b6bda9d14691..caece997d254 100644 --- a/ldso/ldso/arc/dl-sysdep.h +++ b/ldso/ldso/arc/dl-sysdep.h @@ -166,7 +166,7 @@ static __always_inline void elf_machine_relative (Elf32_Addr load_off, const Elf32_Addr rel_addr, Elf32_Word relative_count) { - Elf32_Rel * rpnt = (void *) rel_addr; + Elf32_Rela * rpnt = (void *) rel_addr; --rpnt; do { Elf32_Addr *const reloc_addr = (void *) (load_off + (++rpnt)->r_offset); -- 2.5.0

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uClibc-ng - small C library for embedded systems branch master updated. v1.0.15-1-g3ac3d4e
by wbx＠helium.openadk.org 31 May '16

31 May '16

This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "uClibc-ng - small C library for embedded systems". The branch, master has been updated via 3ac3d4e61a1de0c2d0e0d2bebf0d1b111f153f12 (commit) from 95174cb69c523a1544e5f6f20e47f7d60007e569 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- commit 3ac3d4e61a1de0c2d0e0d2bebf0d1b111f153f12 Author: Waldemar Brodkorb <wbx(a)openadk.org> Date: Tue May 31 20:51:29 2016 +0200 arm: add non-assembly versions of pthread_spin_lock/pthread_spin_trylock Sync pthread_spin_lock/pthread_spin_trylock with GNU libc as it avoids any usage of deprecated SWP instruction. This allows to build uClibc-ng for ARMv8 Cortex-A53 CPU in 32 Bit mode. ----------------------------------------------------------------------- Summary of changes: libpthread/nptl/sysdeps/arm/pthread_spin_lock.S | 30 ---------- libpthread/nptl/sysdeps/arm/pthread_spin_lock.c | 66 ++++++++++++++++++++++ libpthread/nptl/sysdeps/arm/pthread_spin_trylock.S | 33 ----------- .../sysdeps/{sparc => arm}/pthread_spin_trylock.c | 9 ++- 4 files changed, 70 insertions(+), 68 deletions(-) delete mode 100644 libpthread/nptl/sysdeps/arm/pthread_spin_lock.S create mode 100644 libpthread/nptl/sysdeps/arm/pthread_spin_lock.c delete mode 100644 libpthread/nptl/sysdeps/arm/pthread_spin_trylock.S copy libpthread/nptl/sysdeps/{sparc => arm}/pthread_spin_trylock.c (77%) diff --git a/libpthread/nptl/sysdeps/arm/pthread_spin_lock.S b/libpthread/nptl/sysdeps/arm/pthread_spin_lock.S deleted file mode 100644 index a9c07c8..0000000 --- a/libpthread/nptl/sysdeps/arm/pthread_spin_lock.S +++ /dev/null @@ -1,30 +0,0 @@ -/* Copyright (C) 2005 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <sysdep.h> - - .text - .align 4 - -ENTRY (pthread_spin_lock) - mov r1, #1 -1: swp r2, r1, [r0] - teq r2, #0 - bne 1b - mov r0, #0 - PSEUDO_RET_NOERRNO -END (pthread_spin_lock) diff --git a/libpthread/nptl/sysdeps/arm/pthread_spin_lock.c b/libpthread/nptl/sysdeps/arm/pthread_spin_lock.c new file mode 100644 index 0000000..77f5f50 --- /dev/null +++ b/libpthread/nptl/sysdeps/arm/pthread_spin_lock.c @@ -0,0 +1,66 @@ +/* pthread_spin_lock -- lock a spin lock. Generic version. + Copyright (C) 2012-2016 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <atomic.h> +#include "pthreadP.h" + +/* A machine-specific version can define SPIN_LOCK_READS_BETWEEN_CMPXCHG + to the number of plain reads that it's optimal to spin on between uses + of atomic_compare_and_exchange_val_acq. If spinning forever is optimal + then use -1. If no plain reads here would ever be optimal, use 0. */ +#define SPIN_LOCK_READS_BETWEEN_CMPXCHG 1000 + +int +pthread_spin_lock (pthread_spinlock_t *lock) +{ + /* atomic_exchange usually takes less instructions than + atomic_compare_and_exchange. On the other hand, + atomic_compare_and_exchange potentially generates less bus traffic + when the lock is locked. + We assume that the first try mostly will be successful, and we use + atomic_exchange. For the subsequent tries we use + atomic_compare_and_exchange. */ + if (atomic_exchange_acq (lock, 1) == 0) + return 0; + + do + { + /* The lock is contended and we need to wait. Going straight back + to cmpxchg is not a good idea on many targets as that will force + expensive memory synchronizations among processors and penalize other + running threads. + On the other hand, we do want to update memory state on the local core + once in a while to avoid spinning indefinitely until some event that + will happen to update local memory as a side-effect. */ + if (SPIN_LOCK_READS_BETWEEN_CMPXCHG >= 0) + { + int wait = SPIN_LOCK_READS_BETWEEN_CMPXCHG; + + while (*lock != 0 && wait > 0) + --wait; + } + else + { + while (*lock != 0) + ; + } + } + while (atomic_compare_and_exchange_val_acq (lock, 1, 0) != 0); + + return 0; +} diff --git a/libpthread/nptl/sysdeps/arm/pthread_spin_trylock.S b/libpthread/nptl/sysdeps/arm/pthread_spin_trylock.S deleted file mode 100644 index 8ccaffd..0000000 --- a/libpthread/nptl/sysdeps/arm/pthread_spin_trylock.S +++ /dev/null @@ -1,33 +0,0 @@ -/* Copyright (C) 2005 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#define _ERRNO_H 1 -#include <bits/errno.h> - -#include <sysdep.h> - - .text - .align 4 - -ENTRY (pthread_spin_trylock) - mov r1, #1 - swp r2, r1, [r0] - teq r2, #0 - moveq r0, #0 - movne r0, #EBUSY - PSEUDO_RET_NOERRNO -END (pthread_spin_trylock) diff --git a/libpthread/nptl/sysdeps/sparc/pthread_spin_trylock.c b/libpthread/nptl/sysdeps/arm/pthread_spin_trylock.c similarity index 77% copy from libpthread/nptl/sysdeps/sparc/pthread_spin_trylock.c copy to libpthread/nptl/sysdeps/arm/pthread_spin_trylock.c index c1b7b23..4e1a96c 100644 --- a/libpthread/nptl/sysdeps/sparc/pthread_spin_trylock.c +++ b/libpthread/nptl/sysdeps/arm/pthread_spin_trylock.c @@ -1,6 +1,6 @@ -/* Copyright (C) 2003 Free Software Foundation, Inc. +/* pthread_spin_trylock -- trylock a spin lock. Generic version. + Copyright (C) 2012-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. - Contributed by Jakub Jelinek <jakub(a)redhat.com>, 2003. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -17,12 +17,11 @@ <http://www.gnu.org/licenses/>. */ #include <errno.h> +#include <atomic.h> #include "pthreadP.h" int pthread_spin_trylock (pthread_spinlock_t *lock) { - int res; - __asm__ __volatile__ ("ldstub [%1], %0" : "=r" (res) : "r" (lock) : "memory"); - return res == 0 ? 0 : EBUSY; + return atomic_exchange_acq (lock, 1) ? EBUSY : 0; } hooks/post-receive -- uClibc-ng - small C library for embedded systems

1 0

problem in sscanf with different data type, uint8_t, uint16_t, uint32_t
by ayaka 31 May '16

31 May '16

Hi I meet a problem with sscanf(), I want to use this function to parse string into number. But I found the neither uint16_t nor uint8_t could work with %d. Here is the sample code: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdint.h> int main(int argc, char **argv) { uint8_t num1; uint16_t num2; uint32_t num3; sscanf("10", "%d", &num1); sscanf("10", "%d", &num2); sscanf("10", "%d", &num3); printf("input number is %d %d %d\n", num1, num2, num3); return 0; } input number is 0 0 10 But if it is built with glibc at x86_64, the result would be: input number is 0 10 10 I have no idea why the uint8_t doesn't work, but why the uint16_t doesn't work? Here is the config of uclibc, from openwrt # # Automatically generated make config: don't edit # Version: 0.9.33.2 # Sun Mar 20 17:05:37 2016 # # TARGET_alpha is not set # TARGET_arm is not set # TARGET_avr32 is not set # TARGET_bfin is not set # TARGET_c6x is not set # TARGET_cris is not set # TARGET_e1 is not set # TARGET_frv is not set # TARGET_h8300 is not set # TARGET_hppa is not set # TARGET_i386 is not set # TARGET_i960 is not set # TARGET_ia64 is not set # TARGET_m68k is not set # TARGET_microblaze is not set TARGET_mips=y # TARGET_nios is not set # TARGET_nios2 is not set # TARGET_powerpc is not set # TARGET_sh is not set # TARGET_sh64 is not set # TARGET_sparc is not set # TARGET_v850 is not set # TARGET_vax is not set # TARGET_x86_64 is not set # TARGET_xtensa is not set # # Target Architecture Features and Options # TARGET_ARCH="mips" FORCE_OPTIONS_FOR_ARCH=y CONFIG_MIPS_O32_ABI=y # CONFIG_MIPS_N32_ABI is not set # CONFIG_MIPS_N64_ABI is not set # CONFIG_MIPS_ISA_1 is not set # CONFIG_MIPS_ISA_2 is not set # CONFIG_MIPS_ISA_3 is not set # CONFIG_MIPS_ISA_4 is not set CONFIG_MIPS_ISA_MIPS32=y # CONFIG_MIPS_ISA_MIPS32R2 is not set # CONFIG_MIPS_ISA_MIPS64 is not set TARGET_SUBARCH="" # # Using ELF file format # ARCH_ANY_ENDIAN=y ARCH_BIG_ENDIAN=y ARCH_WANTS_BIG_ENDIAN=y # ARCH_WANTS_LITTLE_ENDIAN is not set ARCH_HAS_MMU=y ARCH_USE_MMU=y UCLIBC_HAS_FLOATS=y # UCLIBC_HAS_FPU is not set UCLIBC_HAS_SOFT_FLOAT=y DO_C99_MATH=y # DO_XSI_MATH is not set # UCLIBC_HAS_FENV is not set KERNEL_HEADERS="/home/ayaka/src/openwrt/chaos_calmer/build_dir/toolchain-mips_34kc_gcc-4.8-linaro_uClibc-0.9.33.2/linux-dev/include" HAVE_DOT_CONFIG=y # # General Library Settings # DOPIC=y HAVE_SHARED=y # FORCE_SHAREABLE_TEXT_SEGMENTS is not set LDSO_LDD_SUPPORT=y LDSO_CACHE_SUPPORT=y LDSO_PRELOAD_ENV_SUPPORT=y # LDSO_PRELOAD_FILE_SUPPORT is not set LDSO_BASE_FILENAME="ld.so" # LDSO_STANDALONE_SUPPORT is not set # LDSO_PRELINK_SUPPORT is not set # UCLIBC_STATIC_LDCONFIG is not set LDSO_RUNPATH=y # LDSO_SEARCH_INTERP_PATH is not set LDSO_LD_LIBRARY_PATH=y # LDSO_NO_CLEANUP is not set UCLIBC_CTOR_DTOR=y # LDSO_GNU_HASH_SUPPORT is not set # HAS_NO_THREADS is not set # LINUXTHREADS_OLD is not set # LINUXTHREADS_NEW is not set UCLIBC_HAS_THREADS_NATIVE=y UCLIBC_HAS_THREADS=y UCLIBC_HAS_TLS=y PTHREADS_DEBUG_SUPPORT=y UCLIBC_HAS_SYSLOG=y UCLIBC_HAS_LFS=y # MALLOC is not set # MALLOC_SIMPLE is not set MALLOC_STANDARD=y MALLOC_GLIBC_COMPAT=y UCLIBC_DYNAMIC_ATEXIT=y # COMPAT_ATEXIT is not set UCLIBC_SUSV3_LEGACY=y UCLIBC_SUSV3_LEGACY_MACROS=y UCLIBC_SUSV4_LEGACY=y # UCLIBC_STRICT_HEADERS is not set # UCLIBC_HAS_STUBS is not set UCLIBC_HAS_SHADOW=y UCLIBC_HAS_PROGRAM_INVOCATION_NAME=y UCLIBC_HAS___PROGNAME=y UCLIBC_HAS_PTY=y ASSUME_DEVPTS=y # UNIX98PTY_ONLY is not set UCLIBC_HAS_GETPT=y UCLIBC_HAS_LIBUTIL=y UCLIBC_HAS_TM_EXTENSIONS=y UCLIBC_HAS_TZ_CACHING=y UCLIBC_HAS_TZ_FILE=y UCLIBC_HAS_TZ_FILE_READ_MANY=y UCLIBC_TZ_FILE_PATH="/etc/TZ" # UCLIBC_FALLBACK_TO_ETC_LOCALTIME is not set # # Advanced Library Settings # UCLIBC_PWD_BUFFER_SIZE=256 UCLIBC_GRP_BUFFER_SIZE=256 # # Support various families of functions # UCLIBC_LINUX_MODULE_26=y # UCLIBC_LINUX_MODULE_24 is not set UCLIBC_LINUX_SPECIFIC=y UCLIBC_HAS_GNU_ERROR=y UCLIBC_BSD_SPECIFIC=y UCLIBC_HAS_BSD_ERR=y # UCLIBC_HAS_OBSOLETE_BSD_SIGNAL is not set # UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL is not set # UCLIBC_NTP_LEGACY is not set # UCLIBC_SV4_DEPRECATED is not set UCLIBC_HAS_REALTIME=y UCLIBC_HAS_ADVANCED_REALTIME=y UCLIBC_HAS_EPOLL=y # UCLIBC_HAS_XATTR is not set # UCLIBC_HAS_PROFILING is not set UCLIBC_HAS_CRYPT_IMPL=y # UCLIBC_HAS_SHA256_CRYPT_IMPL is not set # UCLIBC_HAS_SHA512_CRYPT_IMPL is not set UCLIBC_HAS_CRYPT=y UCLIBC_HAS_NETWORK_SUPPORT=y UCLIBC_HAS_SOCKET=y UCLIBC_HAS_IPV4=y UCLIBC_HAS_IPV6=y # UCLIBC_HAS_RPC is not set UCLIBC_USE_NETLINK=y UCLIBC_SUPPORT_AI_ADDRCONFIG=y UCLIBC_HAS_BSD_RES_CLOSE=y UCLIBC_HAS_COMPAT_RES_STATE=y # UCLIBC_HAS_EXTRA_COMPAT_RES_STATE is not set UCLIBC_HAS_RESOLVER_SUPPORT=y UCLIBC_HAS_LIBRESOLV_STUB=y UCLIBC_HAS_LIBNSL_STUB=y # # String and Stdio Support # UCLIBC_HAS_STRING_GENERIC_OPT=y UCLIBC_HAS_STRING_ARCH_OPT=y UCLIBC_HAS_CTYPE_TABLES=y UCLIBC_HAS_CTYPE_SIGNED=y # UCLIBC_HAS_CTYPE_UNSAFE is not set UCLIBC_HAS_CTYPE_CHECKED=y # UCLIBC_HAS_CTYPE_ENFORCED is not set UCLIBC_HAS_WCHAR=y # UCLIBC_HAS_LOCALE is not set UCLIBC_HAS_HEXADECIMAL_FLOATS=y UCLIBC_HAS_GLIBC_CUSTOM_PRINTF=y UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS=9 # UCLIBC_HAS_STDIO_BUFSIZ_NONE is not set # UCLIBC_HAS_STDIO_BUFSIZ_256 is not set # UCLIBC_HAS_STDIO_BUFSIZ_512 is not set # UCLIBC_HAS_STDIO_BUFSIZ_1024 is not set # UCLIBC_HAS_STDIO_BUFSIZ_2048 is not set UCLIBC_HAS_STDIO_BUFSIZ_4096=y # UCLIBC_HAS_STDIO_BUFSIZ_8192 is not set UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE=y # UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4 is not set # UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8 is not set # UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT is not set UCLIBC_HAS_STDIO_GETC_MACRO=y UCLIBC_HAS_STDIO_PUTC_MACRO=y UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION=y # UCLIBC_HAS_FOPEN_LARGEFILE_MODE is not set UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE=y # UCLIBC_HAS_FOPEN_CLOSEEXEC_MODE is not set UCLIBC_HAS_GLIBC_CUSTOM_STREAMS=y UCLIBC_HAS_PRINTF_M_SPEC=y UCLIBC_HAS_ERRNO_MESSAGES=y # UCLIBC_HAS_SYS_ERRLIST is not set UCLIBC_HAS_SIGNUM_MESSAGES=y # UCLIBC_HAS_SYS_SIGLIST is not set UCLIBC_HAS_GNU_GETOPT=y UCLIBC_HAS_STDIO_FUTEXES=y UCLIBC_HAS_GNU_GETSUBOPT=y # # Big and Tall # UCLIBC_HAS_REGEX=y UCLIBC_HAS_REGEX_OLD=y UCLIBC_HAS_FNMATCH=y UCLIBC_HAS_FNMATCH_OLD=y UCLIBC_HAS_WORDEXP=y UCLIBC_HAS_NFTW=y UCLIBC_HAS_FTW=y UCLIBC_HAS_FTS=y UCLIBC_HAS_GLOB=y UCLIBC_HAS_GNU_GLOB=y # UCLIBC_HAS_UTMPX is not set # # Library Installation Options # RUNTIME_PREFIX="/" DEVEL_PREFIX="/usr/" MULTILIB_DIR="lib" # HARDWIRED_ABSPATH is not set # # Security options # # UCLIBC_BUILD_PIE is not set # UCLIBC_HAS_ARC4RANDOM is not set # UCLIBC_HAS_SSP is not set UCLIBC_BUILD_RELRO=y # UCLIBC_BUILD_NOW is not set UCLIBC_BUILD_NOEXECSTACK=y # # Development/debugging options # CROSS_COMPILER_PREFIX="" UCLIBC_EXTRA_CFLAGS="" # DODEBUG is not set DOSTRIP=y # DOASSERTS is not set # SUPPORT_LD_DEBUG is not set # SUPPORT_LD_DEBUG_EARLY is not set # UCLIBC_MALLOC_DEBUGGING is not set # UCLIBC_HAS_BACKTRACE is not set WARNINGS="-Wall" # EXTRA_WARNINGS is not set # DOMULTI is not set # UCLIBC_MJN3_ONLY is not set

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memmove() is failing on MIPS CPU
by Rene Nielsen 29 May '16

29 May '16

I have found a bug in .../libc/string/generic/memmove.c, which is the one that MIPS uses, since there's no specialized, optimized version for MIPS. We're currently using uClibc v. 1.0.12, but I suspect the bug to be present in earlier releases too. Here's a snippet from memmove.c#memmove(): ---------------------oOo--------------------- /* This test makes the forward copying code be used whenever possible. Reduces the working set. */ if (dstp - srcp >= len) /* *Unsigned* compare! */ { #ifndef __ARCH_HAS_BWD_MEMCPY__ /* Backward memcpy implementation cannot be used */ memcpy(dest, src, len); #else /* Copy from the beginning to the end. */ ---------------------oOo--------------------- Given the name of the define (__ARCH_HAS_BWD_MEMCPY__) it sounds as when this is defined, the architecture indeed has backward memcpy() support. But how come the line is preceded by #ifndef and not #ifdef, when the code inside calls memcpy()? Also, the first comment inside the #ifndef seems odd, since memcpy() indeed is called: /* Backward memcpy implementation cannot be used */ Our SDK does not define __ARCH_HAS_BWD_MEMCPY__, so when memmove() resorts to a simple memcpy() that does the wrong thing for overlapping regions, our application fails with disastrous side-effects. I have attached a patch that fixes this. Please CC me in case of any inquiries/replies: rene.nielsen (at) microsemi.com Thanks & regards, Rene Schipp von Branitz Nielsen

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