From 6538c682db9c2b34fbffc22e111a4bcd8f4b02de Mon Sep 17 00:00:00 2001 From: Warner Losh Date: Sun, 13 Aug 2023 10:41:24 +0200 Subject: [PATCH] bsd-user; Update the definitions of __put_user and __get_user macros Use __builtin_choose_expr to avoid type promotion from ?: in __put_user_e and __get_user_e macros. Copied from linux-user/qemu.h, originally by Blue Swirl. Signed-off-by: Warner Losh Signed-off-by: Karim Taha Reviewed-by: Richard Henderson --- bsd-user/qemu.h | 81 ++++++++++++++++++++--------------------------- bsd-user/signal.c | 5 +-- 2 files changed, 35 insertions(+), 51 deletions(-) diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h index 61501c321b..ca791e18b2 100644 --- a/bsd-user/qemu.h +++ b/bsd-user/qemu.h @@ -272,50 +272,37 @@ static inline bool access_ok(int type, abi_ulong addr, abi_ulong size) * These are usually used to access struct data members once the struct has been * locked - usually with lock_user_struct(). */ -#define __put_user(x, hptr)\ -({\ - int size = sizeof(*hptr);\ - switch (size) {\ - case 1:\ - *(uint8_t *)(hptr) = (uint8_t)(typeof(*hptr))(x);\ - break;\ - case 2:\ - *(uint16_t *)(hptr) = tswap16((typeof(*hptr))(x));\ - break;\ - case 4:\ - *(uint32_t *)(hptr) = tswap32((typeof(*hptr))(x));\ - break;\ - case 8:\ - *(uint64_t *)(hptr) = tswap64((typeof(*hptr))(x));\ - break;\ - default:\ - abort();\ - } \ - 0;\ -}) +#define __put_user_e(x, hptr, e) \ + do { \ + PRAGMA_DISABLE_PACKED_WARNING; \ + (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort)))) \ + ((hptr), (x)), (void)0); \ + PRAGMA_REENABLE_PACKED_WARNING; \ + } while (0) -#define __get_user(x, hptr) \ -({\ - int size = sizeof(*hptr);\ - switch (size) {\ - case 1:\ - x = (typeof(*hptr))*(uint8_t *)(hptr);\ - break;\ - case 2:\ - x = (typeof(*hptr))tswap16(*(uint16_t *)(hptr));\ - break;\ - case 4:\ - x = (typeof(*hptr))tswap32(*(uint32_t *)(hptr));\ - break;\ - case 8:\ - x = (typeof(*hptr))tswap64(*(uint64_t *)(hptr));\ - break;\ - default:\ - x = 0;\ - abort();\ - } \ - 0;\ -}) +#define __get_user_e(x, hptr, e) \ + do { \ + PRAGMA_DISABLE_PACKED_WARNING; \ + ((x) = (typeof(*hptr))( \ + __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p, \ + __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort)))) \ + (hptr)), (void)0); \ + PRAGMA_REENABLE_PACKED_WARNING; \ + } while (0) + + +#if TARGET_BIG_ENDIAN +# define __put_user(x, hptr) __put_user_e(x, hptr, be) +# define __get_user(x, hptr) __get_user_e(x, hptr, be) +#else +# define __put_user(x, hptr) __put_user_e(x, hptr, le) +# define __get_user(x, hptr) __get_user_e(x, hptr, le) +#endif /* * put_user()/get_user() take a guest address and check access @@ -328,10 +315,10 @@ static inline bool access_ok(int type, abi_ulong addr, abi_ulong size) ({ \ abi_ulong __gaddr = (gaddr); \ target_type *__hptr; \ - abi_long __ret; \ + abi_long __ret = 0; \ __hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0); \ if (__hptr) { \ - __ret = __put_user((x), __hptr); \ + __put_user((x), __hptr); \ unlock_user(__hptr, __gaddr, sizeof(target_type)); \ } else \ __ret = -TARGET_EFAULT; \ @@ -342,10 +329,10 @@ static inline bool access_ok(int type, abi_ulong addr, abi_ulong size) ({ \ abi_ulong __gaddr = (gaddr); \ target_type *__hptr; \ - abi_long __ret; \ + abi_long __ret = 0; \ __hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1); \ if (__hptr) { \ - __ret = __get_user((x), __hptr); \ + __get_user((x), __hptr); \ unlock_user(__hptr, __gaddr, 0); \ } else { \ (x) = 0; \ diff --git a/bsd-user/signal.c b/bsd-user/signal.c index f4e078ee1d..4db85a3485 100644 --- a/bsd-user/signal.c +++ b/bsd-user/signal.c @@ -787,10 +787,7 @@ static int reset_signal_mask(target_ucontext_t *ucontext) TaskState *ts = (TaskState *)thread_cpu->opaque; for (i = 0; i < TARGET_NSIG_WORDS; i++) { - if (__get_user(target_set.__bits[i], - &ucontext->uc_sigmask.__bits[i])) { - return -TARGET_EFAULT; - } + __get_user(target_set.__bits[i], &ucontext->uc_sigmask.__bits[i]); } target_to_host_sigset_internal(&blocked, &target_set); ts->signal_mask = blocked;