unix: squelch futimens() EPERM on CIFS/SMB shares in copyfile

skooch · skooch · commit 2f65b5f68699 · 2026-03-11T14:44:36.000+11:00
futimens() on CIFS/SMB shares may fail with EPERM because these filesystems do not support setting arbitrary timestamps. Since preserving timestamps during copyfile is best-effort, detect the CIFS/SMB condition using uv__is_cifs_or_smb() and squelch the error, matching the existing handling for fchmod() in the same function. Without this fix, uv_fs_copyfile() fails with EPERM when copying files to CIFS/SMB mounts on Linux (e.g. Alpine containers with mounted cifs shares). Fixes: nodejs/node#56248 Refs: #4396
diff --git a/src/unix/fs.c b/src/unix/fs.c
@@ -1326,7 +1326,20 @@ static ssize_t uv__fs_copyfile(uv_fs_t* req) {
 
   if (futimens(dstfd, times) == -1) {
     err = UV__ERR(errno);
+#ifdef __linux__
+    /* futimens() on CIFS/SMB shares may fail with EPERM. Since preserving
+     * timestamps is best-effort, detect that condition and squelch the error.
+     */
+    if (err != UV_EPERM)
+      goto out;
+
+    if (!uv__is_cifs_or_smb(dstfd))
+      goto out;
+
+    err = 0;
+#else  /* !__linux__ */
     goto out;
+#endif  /* !__linux__ */
   }
 
   /*
