[compiler-rt] [compiler-rt][rtsan] copy_file_range interception for Linux. (PR #129026)

[via llvm-commits]

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@@ -312,6 +312,18 @@ INTERCEPTOR(int, ftruncate64, int fd, off64_t length) {
 #define RTSAN_MAYBE_INTERCEPT_FTRUNCATE64
 #endif
 
+#if SANITIZER_LINUX
+INTERCEPTOR(ssize_t, copy_file_range, int fdin, off_t *off_int, int fdout,
+            off_t *off_out, size_t len, unsigned int flags) {
+  __rtsan_notify_intercepted_call("copy_file_range");
+  return REAL(copy_file_range)(fdin, off_int, fdout, off_out, len, flags);
+}
+#define RTSAN_MAYBE_INTERCEPT_COPY_FILE_RANGE                                  \
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davidtrevelyan wrote:

Ah - sorry - I meant this: it appears like you intend for `copy_file_range` to _always_ be intercepted on Linux. In which case, why introduce `RTSAN_MAYBE_INTERCEPT_COPY_FILE_RANGE` at all? Why not just use `INTERCEPT_FUNCTION` directly (like we do for something such as `ftruncate`)?

https://github.com/llvm/llvm-project/pull/129026