From 12b3b578869d5c25a32edd81950e104a286643d7 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Thu, 11 Feb 2016 18:44:24 +0000 Subject: [iobuf] Improve robustness of I/O buffer allocation Guard against various corner cases (such as zero-length buffers, zero alignments, and integer overflow when rounding up allocation lengths and alignments) and ensure that the struct io_buffer is correctly aligned even when the caller requests a non-zero alignment for the I/O buffer itself. Add self-tests to verify that the resulting alignments and lengths are correct for a range of allocations. Signed-off-by: Michael Brown --- src/tests/iobuf_test.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++++ src/tests/tests.c | 1 + 2 files changed, 137 insertions(+) create mode 100644 src/tests/iobuf_test.c (limited to 'src/tests') diff --git a/src/tests/iobuf_test.c b/src/tests/iobuf_test.c new file mode 100644 index 00000000..a417c2e8 --- /dev/null +++ b/src/tests/iobuf_test.c @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2016 Michael Brown . + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * You can also choose to distribute this program under the terms of + * the Unmodified Binary Distribution Licence (as given in the file + * COPYING.UBDL), provided that you have satisfied its requirements. + */ + +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); + +/** @file + * + * I/O buffer tests + * + */ + +/* Forcibly enable assertions */ +#undef NDEBUG + +#include +#include +#include +#include +#include +#include + +/* Forward declaration */ +struct self_test iobuf_test __self_test; + +/** + * Report I/O buffer allocation test result + * + * @v len Required length of buffer + * @v align Physical alignment + * @v offset Offset from physical alignment + * @v file Test code file + * @v line Test code line + */ +static inline void alloc_iob_okx ( size_t len, size_t align, size_t offset, + const char *file, unsigned int line ) { + struct io_buffer *iobuf; + + /* Allocate I/O buffer */ + iobuf = alloc_iob_raw ( len, align, offset ); + okx ( iobuf != NULL, file, line ); + DBGC ( &iobuf_test, "IOBUF %p (%#08lx+%#zx) for %#zx align %#zx " + "offset %#zx\n", iobuf, virt_to_phys ( iobuf->data ), + iob_tailroom ( iobuf ), len, align, offset ); + + /* Validate requested length and alignment */ + okx ( ( ( ( intptr_t ) iobuf ) & ( __alignof__ ( *iobuf ) - 1 ) ) == 0, + file, line ); + okx ( iob_tailroom ( iobuf ) >= len, file, line ); + okx ( ( ( align == 0 ) || + ( ( virt_to_phys ( iobuf->data ) & ( align - 1 ) ) == + ( offset & ( align - 1 ) ) ) ), file, line ); + + /* Overwrite entire content of I/O buffer (for Valgrind) */ + memset ( iob_put ( iobuf, len ), 0x55, len ); + + /* Free I/O buffer */ + free_iob ( iobuf ); +} +#define alloc_iob_ok( len, align, offset ) \ + alloc_iob_okx ( len, align, offset, __FILE__, __LINE__ ) + +/** + * Report I/O buffer allocation failure test result + * + * @v len Required length of buffer + * @v align Physical alignment + * @v offset Offset from physical alignment + * @v file Test code file + * @v line Test code line + */ +static inline void alloc_iob_fail_okx ( size_t len, size_t align, size_t offset, + const char *file, unsigned int line ) { + struct io_buffer *iobuf; + + /* Allocate I/O buffer */ + iobuf = alloc_iob_raw ( len, align, offset ); + okx ( iobuf == NULL, file, line ); +} +#define alloc_iob_fail_ok( len, align, offset ) \ + alloc_iob_fail_okx ( len, align, offset, __FILE__, __LINE__ ) + +/** + * Perform I/O buffer self-tests + * + */ +static void iobuf_test_exec ( void ) { + + /* Check zero-length allocations */ + alloc_iob_ok ( 0, 0, 0 ); + alloc_iob_ok ( 0, 0, 1 ); + alloc_iob_ok ( 0, 1, 0 ); + alloc_iob_ok ( 0, 1024, 0 ); + alloc_iob_ok ( 0, 139, -17 ); + + /* Check various sensible allocations */ + alloc_iob_ok ( 1, 0, 0 ); + alloc_iob_ok ( 16, 16, 0 ); + alloc_iob_ok ( 64, 0, 0 ); + alloc_iob_ok ( 65, 0, 0 ); + alloc_iob_ok ( 65, 1024, 19 ); + alloc_iob_ok ( 1536, 1536, 0 ); + alloc_iob_ok ( 2048, 2048, 0 ); + alloc_iob_ok ( 2048, 2048, -10 ); + + /* Excessively large or excessively aligned allocations should fail */ + alloc_iob_fail_ok ( -1UL, 0, 0 ); + alloc_iob_fail_ok ( -1UL, 1024, 0 ); + alloc_iob_fail_ok ( 0, -1UL, 0 ); + alloc_iob_fail_ok ( 1024, -1UL, 0 ); +} + +/** I/O buffer self-test */ +struct self_test iobuf_test __self_test = { + .name = "iobuf", + .exec = iobuf_test_exec, +}; diff --git a/src/tests/tests.c b/src/tests/tests.c index 54ce8667..2e67043e 100644 --- a/src/tests/tests.c +++ b/src/tests/tests.c @@ -67,3 +67,4 @@ REQUIRE_OBJECT ( profile_test ); REQUIRE_OBJECT ( setjmp_test ); REQUIRE_OBJECT ( pccrc_test ); REQUIRE_OBJECT ( linebuf_test ); +REQUIRE_OBJECT ( iobuf_test ); -- cgit v1.2.3-55-g7522