Linux: Implements support for EFAULT with ppoll's timeout

Only need to handle the timeout structure, the rest is handled in the kernel itself.
FEX-Emu · Jan 26, 2024 · 929193c · 929193c
1 parent 69ff984
commit 929193c
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Showing 2 changed files with 14 additions and 3 deletions.
diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/x32/FD.cpp b/Source/Tools/LinuxEmulation/LinuxSyscalls/x32/FD.cpp
@@ -263,7 +263,12 @@ namespace FEX::HLE::x32 {
       struct timespec tp64{};
       struct timespec *timed_ptr{};
       if (timeout_ts) {
-        tp64 = *timeout_ts;
+        struct timespec32 timeout{};
+        if (FaultSafeMemcpy::CopyFromUser(&timeout, timeout_ts, sizeof(timeout)) == EFAULT) {
+          return -EFAULT;
+        }
+
+        tp64 = timeout;
         timed_ptr = &tp64;
       }
 
@@ -275,7 +280,13 @@ namespace FEX::HLE::x32 {
         sigsetsize);
 
       if (timeout_ts) {
-        *timeout_ts = tp64;
+        struct timespec32 timeout{};
+        timeout = tp64;
+
+        if (FaultSafeMemcpy::CopyToUser(timeout_ts, &timeout, sizeof(timeout)) == EFAULT) {
+          // Write to user memory failed, this can occur if the timeout is defined in read-only memory.
+          // This is okay to happen, kernel continues happily.
+        }
       }
 
       SYSCALL_ERRNO();

diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/x32/Types.h b/Source/Tools/LinuxEmulation/LinuxSyscalls/x32/Types.h
@@ -127,7 +127,7 @@ timespec32 {
   int32_t tv_sec;
   int32_t tv_nsec;
 
-  timespec32() = delete;
+  timespec32() = default;
 
   operator timespec() const {
     timespec spec{};