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| author | H.J. Lu <hjl.tools@gmail.com> | 2020-04-29 05:35:34 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2020-04-29 05:35:34 -0700 |
| commit | 2ad5d0845d80589d0adf86593bd36a7c71a521f8 (patch) | |
| tree | 81bc0b7de7e0b93604944ed70e4125866547eb39 /sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h | |
| parent | 9207e30d3f070712df6c4175547094be112454d2 (diff) | |
| download | glibc-2ad5d0845d80589d0adf86593bd36a7c71a521f8.zip glibc-2ad5d0845d80589d0adf86593bd36a7c71a521f8.tar.gz glibc-2ad5d0845d80589d0adf86593bd36a7c71a521f8.tar.bz2 | |
Add SYSCALL_ULONG_ARG_[12] to pass long to syscall [BZ #25810]
X32 has 32-bit long and pointer with 64-bit off_t. Since x32 psABI
requires that pointers passed in registers must be zero-extended to
64bit, x32 can share many syscall interfaces with LP64. When a LP64
syscall with long and unsigned long int arguments is used for x32, these
arguments must be properly extended to 64-bit. Otherwise if the upper
32 bits of the register have undefined value, such a syscall will be
rejected by kernel.
For syscalls implemented in assembly codes, 'U' is added to syscall
signature key letters for unsigned long, which is zero-extended to
64-bit types. SYSCALL_ULONG_ARG_1 and SYSCALL_ULONG_ARG_2 are passed
to syscall-template.S for the first and the second unsigned long int
arguments if PSEUDOS_HAVE_ULONG_INDICES is defined. They are used by
x32 to zero-extend 32-bit arguments to 64 bits.
Tested on i386, x86-64 and x32 as well as with build-many-glibcs.py.
Diffstat (limited to 'sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h b/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h index a37d520..62e6f8f 100644 --- a/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h +++ b/sysdeps/unix/sysv/linux/x86_64/x32/sysdep.h @@ -26,7 +26,26 @@ #undef LO_HI_LONG #define LO_HI_LONG(val) (val) -#ifndef __ASSEMBLER__ +#ifdef __ASSEMBLER__ +/* Zero-extend 32-bit unsigned long int arguments to 64 bits. */ +# undef ZERO_EXTEND_1 +# define ZERO_EXTEND_1 movl %edi, %edi; +# undef ZERO_EXTEND_2 +# define ZERO_EXTEND_2 movl %esi, %esi; +# undef ZERO_EXTEND_3 +# define ZERO_EXTEND_3 movl %edx, %edx; +# if SYSCALL_ULONG_ARG_1 == 4 || SYSCALL_ULONG_ARG_2 == 4 +# undef DOARGS_4 +# define DOARGS_4 movl %ecx, %r10d; +# else +# undef ZERO_EXTEND_4 +# define ZERO_EXTEND_4 movl %r10d, %r10d; +# endif +# undef ZERO_EXTEND_5 +# define ZERO_EXTEND_5 movl %r8d, %r8d; +# undef ZERO_EXTEND_6 +# define ZERO_EXTEND_6 movl %r9d, %r9d; +#else /* !__ASSEMBLER__ */ # undef ARGIFY /* Enforce zero-extension for pointers and array system call arguments. For integer types, extend to int64_t (the full register) using a |