remove x32 syscall timespec fixup hacks

the x32 syscall interfaces treat timespec's tv_nsec member as 64-bit
despite the API type being long and long being 32-bit in the ABI. this
is no problem for syscalls that store timespecs to userspace as
results, but caused uninitialized padding to be misinterpreted as the
high bits in syscalls that take timespecs as input.

since the beginning of the port, we've dealt with this situation with
hacks in syscall_arch.h, and injected between __syscall_cp_c and
__syscall_cp_asm, to special-case the syscall numbers that involve
timespecs as inputs and copy them to a form suitable to pass to the
kernel.

commit 40aa18d55ab763e69ad16d0cf1cebea708ffde47 set the stage for
removal of these hacks by letting us treat the "normal" x32 syscalls
dealing with timespec as if they're x32's "time64" syscalls,
effectively making x32 ax "time64-only 32-bit arch" like riscv32 will
be when it's added. since then, all users of syscalls that x32's
syscall_arch.h had hacks for have been updated to use time64 syscalls,
so the hacks can be removed.

there are still at least a few other timespec-related syscalls broken
on x32, which were overlooked when the x32 hacks were done or added
later. these include at least recvmmsg, adjtimex/clock_adjtime, and
timerfd_settime, and they will be fixed independently later on.

diff --git a/arch/x32/syscall_arch.h b/arch/x32/syscall_arch.h
index d05e7341b6261dd40c9778a10049f7b3abbb8a0b..81d1d0df5e5d0d7d257c83722dee8669c5efe0e8 100644 (file)
--- a/arch/x32/syscall_arch.h
+++ b/arch/x32/syscall_arch.h
@@ -3,35 +3,6 @@
 
 #define __scc(X) sizeof(1?(X):0ULL) < 8 ? (unsigned long) (X) : (long long) (X)
 typedef long long syscall_arg_t;
-struct __timespec { long long tv_sec; long tv_nsec; };
-struct __timespec_kernel { long long tv_sec; long long tv_nsec; };
-#define __tsc(X) ((struct __timespec*)(unsigned long)(X))
-#define __fixup(X) do { if(X) { \
-       ts->tv_sec = __tsc(X)->tv_sec; \
-       ts->tv_nsec = __tsc(X)->tv_nsec; \
-       (X) = (unsigned long)ts; } } while(0)
-#define __fixup_case_2 \
-       case SYS_nanosleep: \
-               __fixup(a1); break; \
-       case SYS_clock_settime: \
-               __fixup(a2); break;
-#define __fixup_case_3 \
-       case SYS_clock_nanosleep: case SYS_rt_sigtimedwait: case SYS_ppoll: \
-               __fixup(a3); break; \
-       case SYS_utimensat: \
-               if(a3) { \
-                       ts[0].tv_sec = __tsc(a3)[0].tv_sec; \
-                       ts[0].tv_nsec = __tsc(a3)[0].tv_nsec; \
-                       ts[1].tv_sec = __tsc(a3)[1].tv_sec; \
-                       ts[1].tv_nsec = __tsc(a3)[1].tv_nsec; \
-                       a3 = (unsigned long)ts; \
-               } break;
-#define __fixup_case_4 \
-       case SYS_futex: \
-               if((a2 & (~128 /* FUTEX_PRIVATE_FLAG */)) == 0 /* FUTEX_WAIT */) __fixup(a4); break;
-#define __fixup_case_5 \
-       case SYS_mq_timedsend: case SYS_mq_timedreceive: case SYS_pselect6: \
-               __fixup(a5); break;
 
 static __inline long __syscall0(long long n)
 {
@@ -50,10 +21,6 @@ static __inline long __syscall1(long long n, long long a1)
 static __inline long __syscall2(long long n, long long a1, long long a2)
 {
        unsigned long ret;
-       struct __timespec_kernel ts[1];
-       switch (n) {
-               __fixup_case_2;
-       }
        __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2)
                                        : "rcx", "r11", "memory");
        return ret;
@@ -62,11 +29,6 @@ static __inline long __syscall2(long long n, long long a1, long long a2)
 static __inline long __syscall3(long long n, long long a1, long long a2, long long a3)
 {
        unsigned long ret;
-       struct __timespec_kernel ts[2];
-       switch (n) {
-               __fixup_case_2;
-               __fixup_case_3;
-       }
        __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2),
                                                  "d"(a3) : "rcx", "r11", "memory");
        return ret;
@@ -77,12 +39,6 @@ static __inline long __syscall4(long long n, long long a1, long long a2, long lo
 {
        unsigned long ret;
        register long long a4 __asm__("r10") = a4_;
-       struct __timespec_kernel ts[2];
-       switch (n) {
-               __fixup_case_2;
-               __fixup_case_3;
-               __fixup_case_4;
-       }
        __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2),
                                          "d"(a3), "r"(a4): "rcx", "r11", "memory");
        return ret;
@@ -94,13 +50,6 @@ static __inline long __syscall5(long long n, long long a1, long long a2, long lo
        unsigned long ret;
        register long long a4 __asm__("r10") = a4_;
        register long long a5 __asm__("r8") = a5_;
-       struct __timespec_kernel ts[2];
-       switch (n) {
-               __fixup_case_2;
-               __fixup_case_3;
-               __fixup_case_4;
-               __fixup_case_5;
-       }
        __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2),
                                          "d"(a3), "r"(a4), "r"(a5) : "rcx", "r11", "memory");
        return ret;
@@ -113,13 +62,6 @@ static __inline long __syscall6(long long n, long long a1, long long a2, long lo
        register long long a4 __asm__("r10") = a4_;
        register long long a5 __asm__("r8") = a5_;
        register long long a6 __asm__("r9") = a6_;
-       struct __timespec_kernel ts[2];
-       switch (n) {
-               __fixup_case_2;
-               __fixup_case_3;
-               __fixup_case_4;
-               __fixup_case_5;
-       }
        __asm__ __volatile__ ("syscall" : "=a"(ret) : "a"(n), "D"(a1), "S"(a2),
                                          "d"(a3), "r"(a4), "r"(a5), "r"(a6) : "rcx", "r11", "memory");
        return ret;

diff --git a/src/thread/x32/syscall_cp.s b/src/thread/x32/syscall_cp.s
index 9805af0ae98996a7d2d6d9c7680c140689d82068..4f101716d4ee0cd50461f45a0da6b2edb2be3d4c 100644 (file)
--- a/src/thread/x32/syscall_cp.s
+++ b/src/thread/x32/syscall_cp.s
@@ -6,10 +6,10 @@
 .global __cp_cancel
 .hidden __cp_cancel
 .hidden __cancel
-.global __syscall_cp_internal
-.hidden __syscall_cp_internal
-.type   __syscall_cp_internal,@function
-__syscall_cp_internal:
+.global __syscall_cp_asm
+.hidden __syscall_cp_asm
+.type   __syscall_cp_asm,@function
+__syscall_cp_asm:
 
 __cp_begin:
        mov (%rdi),%eax

diff --git a/src/thread/x32/syscall_cp_fixup.c b/src/thread/x32/syscall_cp_fixup.c
deleted file mode 100644 (file)
index 4956610..0000000
--- a/src/thread/x32/syscall_cp_fixup.c
+++ /dev/null
@@ -1,39 +0,0 @@
-#include <sys/syscall.h>
-#include <features.h>
-
-hidden long __syscall_cp_internal(volatile void*, long long, long long,
-                                  long long, long long, long long,
-                                  long long, long long);
-
-struct __timespec { long long tv_sec; long tv_nsec; };
-struct __timespec_kernel { long long tv_sec; long long tv_nsec; };
-#define __tsc(X) ((struct __timespec*)(unsigned long)(X))
-#define __fixup(X) do { if(X) { \
-       ts->tv_sec = __tsc(X)->tv_sec; \
-       ts->tv_nsec = __tsc(X)->tv_nsec; \
-       (X) = (unsigned long)ts; } } while(0)
-
-hidden long __syscall_cp_asm (volatile void * foo, long long n, long long a1,
-                              long long a2, long long a3, long long a4,
-                              long long a5, long long a6)
-{
-       struct __timespec_kernel ts[1];
-       switch (n) {
-       case SYS_mq_timedsend: case SYS_mq_timedreceive: case SYS_pselect6:
-               __fixup(a5);
-               break;
-       case SYS_futex:
-               if((a2 & (~128 /* FUTEX_PRIVATE_FLAG */)) == 0 /* FUTEX_WAIT */)
-                       __fixup(a4);
-               break;
-       case SYS_clock_nanosleep:
-       case SYS_rt_sigtimedwait: case SYS_ppoll:
-               __fixup(a3);
-               break;
-       case SYS_nanosleep:
-               __fixup(a1);
-               break;
-       }
-       return __syscall_cp_internal(foo, n, a1, a2, a3, a4, a5, a6);
-}
-