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94 lines
3.5 KiB
94 lines
3.5 KiB
commit 1a5b9d1a231ae788aac3520dab07dc856e404c69 |
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Author: Florian Weimer <fweimer@redhat.com> |
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Date: Wed May 4 15:37:21 2022 +0200 |
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i386: Honor I386_USE_SYSENTER for 6-argument Linux system calls |
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Introduce an int-80h-based version of __libc_do_syscall and use |
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it if I386_USE_SYSENTER is defined as 0. |
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Reviewed-by: H.J. Lu <hjl.tools@gmail.com> |
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(cherry picked from commit 60f0f2130d30cfd008ca39743027f1e200592dff) |
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diff --git a/sysdeps/unix/sysv/linux/i386/Makefile b/sysdeps/unix/sysv/linux/i386/Makefile |
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index abd0009d58f06303..e379a2e767d96322 100644 |
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--- a/sysdeps/unix/sysv/linux/i386/Makefile |
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+++ b/sysdeps/unix/sysv/linux/i386/Makefile |
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@@ -14,7 +14,7 @@ install-bin += lddlibc4 |
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endif |
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ifeq ($(subdir),io) |
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-sysdep_routines += libc-do-syscall |
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+sysdep_routines += libc-do-syscall libc-do-syscall-int80 |
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endif |
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ifeq ($(subdir),stdlib) |
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diff --git a/sysdeps/unix/sysv/linux/i386/libc-do-syscall-int80.S b/sysdeps/unix/sysv/linux/i386/libc-do-syscall-int80.S |
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new file mode 100644 |
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index 0000000000000000..2c472f255734b357 |
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--- /dev/null |
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+++ b/sysdeps/unix/sysv/linux/i386/libc-do-syscall-int80.S |
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@@ -0,0 +1,25 @@ |
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+/* Out-of-line syscall stub for six-argument syscalls from C. For static PIE. |
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+ Copyright (C) 2022 Free Software Foundation, Inc. |
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+ This file is part of the GNU C Library. |
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+ |
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+ The GNU C Library is free software; you can redistribute it and/or |
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+ modify it under the terms of the GNU Lesser General Public |
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+ License as published by the Free Software Foundation; either |
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+ version 2.1 of the License, or (at your option) any later version. |
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+ |
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+ The GNU C Library is distributed in the hope that it will be useful, |
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+ but WITHOUT ANY WARRANTY; without even the implied warranty of |
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+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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+ Lesser General Public License for more details. |
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+ |
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+ You should have received a copy of the GNU Lesser General Public |
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+ License along with the GNU C Library; if not, see |
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+ <https://www.gnu.org/licenses/>. */ |
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+ |
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+#ifndef SHARED |
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+# define I386_USE_SYSENTER 0 |
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+# include <sysdep.h> |
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+ |
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+# define __libc_do_syscall __libc_do_syscall_int80 |
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+# include "libc-do-syscall.S" |
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+#endif |
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diff --git a/sysdeps/unix/sysv/linux/i386/sysdep.h b/sysdeps/unix/sysv/linux/i386/sysdep.h |
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index 39d6a3c13427abb5..4c6358c7fe43fe0b 100644 |
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--- a/sysdeps/unix/sysv/linux/i386/sysdep.h |
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+++ b/sysdeps/unix/sysv/linux/i386/sysdep.h |
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@@ -43,6 +43,15 @@ |
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# endif |
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#endif |
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+#if !I386_USE_SYSENTER && IS_IN (libc) && !defined SHARED |
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+/* Inside static libc, we have two versions. For compilation units |
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+ with !I386_USE_SYSENTER, the vDSO entry mechanism cannot be |
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+ used. */ |
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+# define I386_DO_SYSCALL_STRING "__libc_do_syscall_int80" |
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+#else |
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+# define I386_DO_SYSCALL_STRING "__libc_do_syscall" |
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+#endif |
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+ |
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#ifdef __ASSEMBLER__ |
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/* Linux uses a negative return value to indicate syscall errors, |
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@@ -302,7 +311,7 @@ struct libc_do_syscall_args |
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}; \ |
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asm volatile ( \ |
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"movl %1, %%eax\n\t" \ |
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- "call __libc_do_syscall" \ |
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+ "call " I386_DO_SYSCALL_STRING \ |
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: "=a" (resultvar) \ |
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: "i" (__NR_##name), "c" (arg2), "d" (arg3), "S" (arg4), "D" (&_xv) \ |
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: "memory", "cc") |
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@@ -316,7 +325,7 @@ struct libc_do_syscall_args |
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}; \ |
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asm volatile ( \ |
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"movl %1, %%eax\n\t" \ |
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- "call __libc_do_syscall" \ |
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+ "call " I386_DO_SYSCALL_STRING \ |
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: "=a" (resultvar) \ |
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: "a" (name), "c" (arg2), "d" (arg3), "S" (arg4), "D" (&_xv) \ |
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: "memory", "cc")
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