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author | H.J. Lu <hjl.tools@gmail.com> | 2015-12-16 06:50:42 -0800 |
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committer | H.J. Lu <hjl.tools@gmail.com> | 2015-12-16 06:50:42 -0800 |
commit | bf0e161423748feb7950110d6074ebbcd102cb7e (patch) | |
tree | 2ea352f400a4e4da763965639fc6550c84768db6 /sysdeps | |
parent | 4c0dfefbdf950080746e48f6f95f449922bb5d0c (diff) | |
download | glibc-hjl/pr19371/master.zip glibc-hjl/pr19371/master.tar.gz glibc-hjl/pr19371/master.tar.bz2 |
Properly handle x32 syscallhjl/pr19371/master
X32 syscall() may return 64-bit integer as lseek, time and times. Its
return type should be __syscall_slong_t instead of long int. We need
to properly return 64-bit error value.
Before the patch:
Dump of assembler code for function syscall:
0x000dab20 <+0>: mov %rdi,%rax
0x000dab23 <+3>: mov %rsi,%rdi
0x000dab26 <+6>: mov %rdx,%rsi
0x000dab29 <+9>: mov %rcx,%rdx
0x000dab2c <+12>: mov %r8,%r10
0x000dab2f <+15>: mov %r9,%r8
0x000dab32 <+18>: mov 0x8(%rsp),%r9
0x000dab37 <+23>: syscall
0x000dab39 <+25>: cmp $0xfffffffffffff001,%rax
0x000dab3f <+31>: jae 0xdab42 <syscall+34>
0x000dab41 <+33>: retq
0x000dab42 <+34>: mov 0x2b3367(%rip),%rcx # 0x38deb0
0x000dab49 <+41>: neg %eax
0x000dab4b <+43>: mov %eax,%fs:(%rcx)
0x000dab4e <+46>: or $0xffffffff,%eax
^^^^^^^^^^^^^^^^^^ This is 32-bit error return.
0x000dab51 <+49>: retq
End of assembler dump.
After the patch:
Dump of assembler code for function syscall:
0x000daaf0 <+0>: mov %rdi,%rax
0x000daaf3 <+3>: mov %rsi,%rdi
0x000daaf6 <+6>: mov %rdx,%rsi
0x000daaf9 <+9>: mov %rcx,%rdx
0x000daafc <+12>: mov %r8,%r10
0x000daaff <+15>: mov %r9,%r8
0x000dab02 <+18>: mov 0x8(%rsp),%r9
0x000dab07 <+23>: syscall
0x000dab09 <+25>: cmp $0xfffffffffffff001,%rax
0x000dab0f <+31>: jae 0xdab12 <syscall+34>
0x000dab11 <+33>: retq
0x000dab12 <+34>: mov 0x2b3397(%rip),%rcx # 0x38deb0
0x000dab19 <+41>: neg %eax
0x000dab1b <+43>: mov %eax,%fs:(%rcx)
0x000dab1e <+46>: or $0xffffffffffffffff,%rax
0x000dab22 <+50>: retq
End of assembler dump.
[BZ #19371]
* posix/unistd.h (syscall): Use __syscall_slong_t for return
type.
* sysdeps/unix/sysv/linux/x86_64/x32/syscall.S: New file.
Diffstat (limited to 'sysdeps')
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/x32/syscall.S | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/syscall.S b/sysdeps/unix/sysv/linux/x86_64/x32/syscall.S new file mode 100644 index 0000000..cc5255f --- /dev/null +++ b/sysdeps/unix/sysv/linux/x86_64/x32/syscall.S @@ -0,0 +1,33 @@ +/* The syscall system call. Linux/x32 version. + Copyright (C) 2015 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> + +/* Return -1LL in a full 64 bits. */ +#undef SYSCALL_ERROR_HANDLER +#define SYSCALL_ERROR_HANDLER \ +0: \ + SYSCALL_SET_ERRNO; \ + orq $-1, %rax; \ + ret; + +/* Always use our own error handler. */ +#undef SYSCALL_ERROR_LABEL +#define SYSCALL_ERROR_LABEL 0f + +#include <sysdeps/unix/sysv/linux/x86_64/syscall.S> |