make ADIOI_Shfp_fname report errors

Right now there's only one error condition: file name too long.  This
change checks return codes of ADIOI_Strncpy and informs caller.
Otherwise, really long names result in buffer overruns.

See #2212
Signed-off-by: Ken Raffenetti <raffenet@mcs.anl.gov>

src/mpi/romio/adio/common/shfp_fname.c

@@ -26,7 +26,7 @@
    file pointer functions are used and is deleted when the real
    file is closed. */
 
-void ADIOI_Shfp_fname(ADIO_File fd, int rank)
+void ADIOI_Shfp_fname(ADIO_File fd, int rank, int *error_code)
 {
     int i;
     int len;
@@ -40,7 +40,11 @@ void ADIOI_Shfp_fname(ADIO_File fd, int rank)
         i = rand();
 	pid = (int)getpid();
 	
-	ADIOI_Strncpy(fd->shared_fp_fname, fd->filename, 256);
+	if (ADIOI_Strncpy(fd->shared_fp_fname, fd->filename, 256)) {
+	    *error_code = ADIOI_Err_create_code("ADIOI_Shfp_fname",
+		    fd->filename, ENAMETOOLONG);
+	    return;
+	}
 	
 #ifdef ROMIO_NTFS
 	slash = strrchr(fd->filename, '\\');
@@ -48,8 +52,16 @@ void ADIOI_Shfp_fname(ADIO_File fd, int rank)
 	slash = strrchr(fd->filename, '/');
 #endif
 	if (!slash) {
-	    ADIOI_Strncpy(fd->shared_fp_fname, ".", 2);
-	    ADIOI_Strncpy(fd->shared_fp_fname + 1, fd->filename, 255);
+	    if (ADIOI_Strncpy(fd->shared_fp_fname, ".", 2)) {
+		*error_code = ADIOI_Err_create_code("ADIOI_Shfp_fname",
+			fd->filename, ENAMETOOLONG);
+		return;
+	    }
+	    if (ADIOI_Strncpy(fd->shared_fp_fname + 1, fd->filename, 255)) {
+		*error_code = ADIOI_Err_create_code("ADIOI_Shfp_fname",
+			fd->filename, ENAMETOOLONG);
+		return;
+	    }
 	}
 	else {
 	    ptr = slash;
@@ -58,13 +70,22 @@ void ADIOI_Shfp_fname(ADIO_File fd, int rank)
 #else
 	    slash = strrchr(fd->shared_fp_fname, '/');
 #endif
-	    ADIOI_Strncpy(slash + 1, ".", 2);
+	    if (ADIOI_Strncpy(slash + 1, ".", 2))  {
+		*error_code = ADIOI_Err_create_code("ADIOI_Shfp_fname",
+			fd->filename, ENAMETOOLONG);
+		return;
+	    }
 	    /* ok to cast: file names bounded by PATH_MAX and NAME_MAX */
 	    len = (int) (256 - (slash+2 - fd->shared_fp_fname));
-	    ADIOI_Strncpy(slash + 2, ptr + 1, len);
+	    if (ADIOI_Strncpy(slash + 2, ptr + 1, len)) {
+		*error_code = ADIOI_Err_create_code("ADIOI_Shfp_fname",
+			ptr + 1, ENAMETOOLONG);
+		return;
+	    }
 	}
 	    
 	ADIOI_Snprintf(tmp, 128, ".shfp.%d.%d", pid, i);
+	/* ADIOI_Strnapp will return non-zero if truncated.  That's ok */
 	ADIOI_Strnapp(fd->shared_fp_fname, tmp, 256);
 	
 	len = (int)strlen(fd->shared_fp_fname);

src/mpi/romio/adio/include/adioi.h

@@ -691,7 +691,7 @@ ADIO_Offset ADIOI_GEN_SeekIndividual(ADIO_File fd, ADIO_Offset offset,
 void ADIOI_GEN_Resize(ADIO_File fd, ADIO_Offset size, int *error_code);
 void ADIOI_GEN_SetInfo(ADIO_File fd, MPI_Info users_info, int *error_code);
 void ADIOI_GEN_Close(ADIO_File fd, int *error_code);
-void ADIOI_Shfp_fname(ADIO_File fd, int rank);
+void ADIOI_Shfp_fname(ADIO_File fd, int rank, int *error_code);
 void ADIOI_GEN_Prealloc(ADIO_File fd, ADIO_Offset size, int *error_code);
 int ADIOI_Error(ADIO_File fd, int error_code, char *string);
 int MPIR_Err_setmsg( int, int, const char *, const char *, const char *, ... );

src/mpi/romio/mpi-io/open.c

@@ -179,7 +179,9 @@ int MPI_File_open(MPI_Comm comm, ROMIO_CONST char *filename, int amode,
     if ((error_code == MPI_SUCCESS) && 
 		    ADIO_Feature((*fh), ADIO_SHARED_FP)) {
 	MPI_Comm_rank(dupcomm, &rank);
-	ADIOI_Shfp_fname(*fh, rank);
+	ADIOI_Shfp_fname(*fh, rank, &error_code);
+	if (error_code != MPI_SUCCESS)
+	    goto fn_fail;
 
         /* if MPI_MODE_APPEND, set the shared file pointer to end of file.
            indiv. file pointer already set to end of file in ADIO_Open.