diff options
| -rw-r--r-- | meta/recipes-core/eglibc/eglibc-2.18/ppc-fix-time-related-syscalls.patch | 227 | ||||
| -rw-r--r-- | meta/recipes-core/eglibc/eglibc_2.18.bb | 1 |
2 files changed, 228 insertions, 0 deletions
diff --git a/meta/recipes-core/eglibc/eglibc-2.18/ppc-fix-time-related-syscalls.patch b/meta/recipes-core/eglibc/eglibc-2.18/ppc-fix-time-related-syscalls.patch new file mode 100644 index 0000000000..c2373c53cc --- /dev/null +++ b/meta/recipes-core/eglibc/eglibc-2.18/ppc-fix-time-related-syscalls.patch @@ -0,0 +1,227 @@ +Upstream-Status: Backport + +Concatenated fix of PowerPC time related system calls in eglibc 2.18 taken +from upstream glibc. Eglibc 2.17 does not have this issue and the patches are +already part of 2.19. +This compilation includes the following committs: + + +PowerPC: Fix vDSO missing ODP entries + +author Adhemerval Zanella <azanella@linux.vnet.ibm.com> + Thu, 7 Nov 2013 11:34:22 +0000 (05:34 -0600) + +This patch fixes the vDSO symbol used directed in IFUNC resolver where +they do not have an associated ODP entry leading to undefined behavior +in some cases. It adds an artificial OPD static entry to such cases +and set its TOC to non 0 to avoid triggering lazy resolutions. + + +Update copyright notices with scripts/update-copyrights + +author Allan McRae <allan@archlinux.org> + Wed, 1 Jan 2014 11:03:15 +0000 (21:03 +1000) + +((Only for files otherwise touched by this patch)) + + +PowerPC: Fix ftime gettimeofday internal call returning bogus data + +author Adhemerval Zanella <azanella@linux.vnet.ibm.com> + Thu, 16 Jan 2014 12:53:18 +0000 (06:53 -0600) + +This patches fixes BZ#16430 by setting a different symbol for internal +GLIBC calls that points to ifunc resolvers. For PPC32, if the symbol +is defined as hidden (which is the case for gettimeofday and time) the +compiler will create local branches (symbol@local) and linker will not +create PLT calls (required for IFUNC). This will leads to internal symbol +calling the IFUNC resolver instead of the resolved symbol. +For PPC64 this behavior does not occur because a call to a function in +another translation unit might use a different toc pointer thus requiring +a PLT call. + + +PowerPC: Fix gettimeofday ifunc selection + +author Adhemerval Zanella <azanella@linux.vnet.ibm.com> + Mon, 20 Jan 2014 18:29:51 +0000 (12:29 -0600) + +The IFUNC selector for gettimeofday runs before _libc_vdso_platform_setup where +__vdso_gettimeofday is set. The selector then sets __gettimeofday (the internal +version used within GLIBC) to use the system call version instead of the vDSO one. +This patch changes the check if vDSO is available to get its value directly +instead of rely on __vdso_gettimeofday. + +This patch changes it by getting the vDSO value directly. + +It fixes BZ#16431. + + +--- +diff -pruN libc.orig/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h libc/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h +--- libc.orig/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h ++++ libc/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h +@@ -1,5 +1,5 @@ + /* Resolve function pointers to VDSO functions. +- Copyright (C) 2005-2013 Free Software Foundation, Inc. ++ Copyright (C) 2005-2014 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 +@@ -34,12 +34,32 @@ extern void *__vdso_getcpu; + + extern void *__vdso_time; + +-/* This macro is needed for PPC64 to return a skeleton OPD entry of a vDSO +- symbol. This works because _dl_vdso_vsym always return the function +- address, and no vDSO symbols use the TOC or chain pointers from the OPD +- so we can allow them to be garbage. */ + #if defined(__PPC64__) || defined(__powerpc64__) +-#define VDSO_IFUNC_RET(value) ((void *) &(value)) ++/* The correct solution is for _dl_vdso_vsym to return the address of the OPD ++ for the kernel VDSO function. That address would then be stored in the ++ __vdso_* variables and returned as the result of the IFUNC resolver function. ++ Yet, the kernel does not contain any OPD entries for the VDSO functions ++ (incomplete implementation). However, PLT relocations for IFUNCs still expect ++ the address of an OPD to be returned from the IFUNC resolver function (since ++ PLT entries on PPC64 are just copies of OPDs). The solution for now is to ++ create an artificial static OPD for each VDSO function returned by a resolver ++ function. The TOC value is set to a non-zero value to avoid triggering lazy ++ symbol resolution via .glink0/.plt0 for a zero TOC (requires thread-safe PLT ++ sequences) when the dynamic linker isn't prepared for it e.g. RTLD_NOW. None ++ of the kernel VDSO routines use the TOC or AUX values so any non-zero value ++ will work. Note that function pointer comparisons will not use this artificial ++ static OPD since those are resolved via ADDR64 relocations and will point at ++ the non-IFUNC default OPD for the symbol. Lastly, because the IFUNC relocations ++ are processed immediately at startup the resolver functions and this code need ++ not be thread-safe, but if the caller writes to a PLT slot it must do so in a ++ thread-safe manner with all the required barriers. */ ++#define VDSO_IFUNC_RET(value) \ ++ ({ \ ++ static Elf64_FuncDesc vdso_opd = { .fd_toc = ~0x0 }; \ ++ vdso_opd.fd_func = (Elf64_Addr)value; \ ++ &vdso_opd; \ ++ }) ++ + #else + #define VDSO_IFUNC_RET(value) ((void *) (value)) + #endif +diff -pruN libc.orig/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c libc/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c +--- libc.orig/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c ++++ libc/sysdeps/unix/sysv/linux/powerpc/gettimeofday.c +@@ -1,4 +1,4 @@ +-/* Copyright (C) 2005-2013 Free Software Foundation, Inc. ++/* Copyright (C) 2005-2014 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 +@@ -22,6 +22,7 @@ + + # include <dl-vdso.h> + # include <bits/libc-vdso.h> ++# include <dl-machine.h> + + void *gettimeofday_ifunc (void) __asm__ ("__gettimeofday"); + +@@ -34,17 +35,36 @@ __gettimeofday_syscall (struct timeval * + void * + gettimeofday_ifunc (void) + { ++ PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); ++ + /* If the vDSO is not available we fall back syscall. */ +- return (__vdso_gettimeofday ? VDSO_IFUNC_RET (__vdso_gettimeofday) +- : __gettimeofday_syscall); ++ void *vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615); ++ return (vdso_gettimeofday ? VDSO_IFUNC_RET (vdso_gettimeofday) ++ : (void*)__gettimeofday_syscall); + } + asm (".type __gettimeofday, %gnu_indirect_function"); + + /* This is doing "libc_hidden_def (__gettimeofday)" but the compiler won't + let us do it in C because it doesn't know we're defining __gettimeofday + here in this file. */ +-asm (".globl __GI___gettimeofday\n" +- "__GI___gettimeofday = __gettimeofday"); ++asm (".globl __GI___gettimeofday"); ++ ++/* __GI___gettimeofday is defined as hidden and for ppc32 it enables the ++ compiler make a local call (symbol@local) for internal GLIBC usage. It ++ means the PLT won't be used and the ifunc resolver will be called directly. ++ For ppc64 a call to a function in another translation unit might use a ++ different toc pointer thus disallowing direct branchess and making internal ++ ifuncs calls safe. */ ++#ifdef __powerpc64__ ++asm ("__GI___gettimeofday = __gettimeofday"); ++#else ++int ++__gettimeofday_vsyscall (struct timeval *tv, struct timezone *tz) ++{ ++ return INLINE_VSYSCALL (gettimeofday, 2, tv, tz); ++} ++asm ("__GI___gettimeofday = __gettimeofday_vsyscall"); ++#endif + + #else + +diff -pruN libc.orig/sysdeps/unix/sysv/linux/powerpc/time.c libc/sysdeps/unix/sysv/linux/powerpc/time.c +--- libc.orig/sysdeps/unix/sysv/linux/powerpc/time.c ++++ libc/sysdeps/unix/sysv/linux/powerpc/time.c +@@ -1,5 +1,5 @@ + /* time system call for Linux/PowerPC. +- Copyright (C) 2013 Free Software Foundation, Inc. ++ Copyright (C) 2013-2014 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 +@@ -20,7 +20,9 @@ + + # include <time.h> + # include <sysdep.h> ++# include <dl-vdso.h> + # include <bits/libc-vdso.h> ++# include <dl-machine.h> + + void *time_ifunc (void) asm ("time"); + +@@ -43,17 +45,36 @@ time_syscall (time_t *t) + void * + time_ifunc (void) + { ++ PREPARE_VERSION (linux2615, "LINUX_2.6.15", 123718565); ++ + /* If the vDSO is not available we fall back to the syscall. */ +- return (__vdso_time ? VDSO_IFUNC_RET (__vdso_time) +- : time_syscall); ++ void *vdso_time = _dl_vdso_vsym ("__kernel_time", &linux2615); ++ return (vdso_time ? VDSO_IFUNC_RET (vdso_time) ++ : (void*)time_syscall); + } + asm (".type time, %gnu_indirect_function"); + + /* This is doing "libc_hidden_def (time)" but the compiler won't + * let us do it in C because it doesn't know we're defining time + * here in this file. */ +-asm (".globl __GI_time\n" +- "__GI_time = time"); ++asm (".globl __GI_time"); ++ ++/* __GI_time is defined as hidden and for ppc32 it enables the ++ compiler make a local call (symbol@local) for internal GLIBC usage. It ++ means the PLT won't be used and the ifunc resolver will be called directly. ++ For ppc64 a call to a function in another translation unit might use a ++ different toc pointer thus disallowing direct branchess and making internal ++ ifuncs calls safe. */ ++#ifdef __powerpc64__ ++asm ("__GI_time = time"); ++#else ++time_t ++__time_vsyscall (time_t *t) ++{ ++ return INLINE_VSYSCALL (time, 1, t); ++} ++asm ("__GI_time = __time_vsyscall"); ++#endif + + #else + diff --git a/meta/recipes-core/eglibc/eglibc_2.18.bb b/meta/recipes-core/eglibc/eglibc_2.18.bb index 15e5eed3ff..43f43ae2b0 100644 --- a/meta/recipes-core/eglibc/eglibc_2.18.bb +++ b/meta/recipes-core/eglibc/eglibc_2.18.bb @@ -28,6 +28,7 @@ SRC_URI = "http://downloads.yoctoproject.org/releases/eglibc/eglibc-${PV}-svnr23 file://fix-tibetian-locales.patch \ file://0001-ARM-Pass-dl_hwcap-to-IFUNC-resolver.patch \ file://make-4.patch \ + file://ppc-fix-time-related-syscalls.patch \ " SRC_URI[md5sum] = "b395b021422a027d89884992e91734fc" SRC_URI[sha256sum] = "15f564b45dc5dd65faf0875579e3447961ae61e876933384ae05d19328539ad4" |