From: Christian A. Ehrhardt Date: Thu, 26 Mar 2026 21:49:05 +0000 (+0100) Subject: lib: kunit_iov_iter: add tests for extract_iter_to_sg X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0913b7554726aac089cab89b6f0877dafc30b2a0;p=thirdparty%2Flinux.git lib: kunit_iov_iter: add tests for extract_iter_to_sg Add test cases that test extract_iter_to_sg. For each iterator type an iterator is loaded with a suitable buffer. The iterator is then extracted to a scatterlist with multiple calls to extract_iter_to_sg. The final scatterlist is copied into a scratch buffer. The test passes if the scratch buffer contains the same data as the original buffer. The new tests demonstrate bugs in extract_iter_to_sg for kvec and user iterators that are fixed by the previous commits. Link: https://lkml.kernel.org/r/20260326214905.818170-6-lk@c--e.de Signed-off-by: Christian A. Ehrhardt Cc: David Howells Cc: David Gow Cc: Kees Cook Cc: Petr Mladek Signed-off-by: Andrew Morton --- diff --git a/lib/tests/kunit_iov_iter.c b/lib/tests/kunit_iov_iter.c index 64a4e2f3eafa9..37bd6eb258960 100644 --- a/lib/tests/kunit_iov_iter.c +++ b/lib/tests/kunit_iov_iter.c @@ -13,7 +13,9 @@ #include #include #include +#include #include +#include #include MODULE_DESCRIPTION("iov_iter testing"); @@ -1016,6 +1018,202 @@ stop: KUNIT_SUCCEED(test); } +struct iov_kunit_iter_to_sg_data { + struct sg_table *sgt; + u8 *buffer, *scratch; + u8 __user *ubuf; + struct page **pages; + size_t npages; +}; + +static void __init +iov_kunit_iter_unpin_sgt(void *data) +{ + struct sg_table *sgt = data; + + for (unsigned int i = 0; i < sgt->nents; ++i) + unpin_user_page(sg_page(&sgt->sgl[i])); +} + +static void __init +iov_kunit_iter_to_sg_init(struct kunit *test, size_t bufsize, bool user, + struct iov_kunit_iter_to_sg_data *data) +{ + struct page **spages; + struct scatterlist *sg; + unsigned long uaddr; + size_t i; + + data->npages = bufsize / PAGE_SIZE; + sg = kunit_kmalloc_array(test, data->npages, sizeof(*sg), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sg); + sg_init_table(sg, data->npages); + data->sgt = kunit_kzalloc(test, sizeof(*data->sgt), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, data->sgt); + data->sgt->orig_nents = 0; + data->sgt->sgl = sg; + + data->buffer = NULL; + data->ubuf = NULL; + if (user) { + uaddr = kunit_vm_mmap(test, NULL, 0, bufsize, + PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, 0); + KUNIT_ASSERT_NE(test, uaddr, 0); + data->ubuf = (u8 __user *)uaddr; + for (i = 0; i < bufsize; ++i) + put_user(pattern(i), data->ubuf + i); + } else { + data->buffer = iov_kunit_create_buffer(test, &data->pages, + data->npages); + for (i = 0; i < bufsize; ++i) + data->buffer[i] = pattern(i); + } + data->scratch = iov_kunit_create_buffer(test, &spages, data->npages); + memset(data->scratch, 0, bufsize); +} + +static void __init +iov_kunit_iter_to_sg_check(struct kunit *test, struct iov_iter *iter, + size_t bufsize, + struct iov_kunit_iter_to_sg_data *data) +{ + static const size_t tail = 16 * PAGE_SIZE; + size_t i; + + KUNIT_ASSERT_LT(test, tail, bufsize); + + if (iov_iter_extract_will_pin(iter)) + kunit_add_action_or_reset(test, iov_kunit_iter_unpin_sgt, + data->sgt); + + i = extract_iter_to_sg(iter, bufsize, data->sgt, 0, 0); + KUNIT_ASSERT_EQ(test, i, 0); + KUNIT_ASSERT_EQ(test, data->sgt->nents, 0); + + i = extract_iter_to_sg(iter, bufsize - tail, data->sgt, 1, 0); + KUNIT_ASSERT_LE(test, i, bufsize - tail); + KUNIT_ASSERT_EQ(test, data->sgt->nents, 1); + + i += extract_iter_to_sg(iter, bufsize - tail - i, data->sgt, + data->npages - data->sgt->nents, 0); + KUNIT_ASSERT_EQ(test, i, bufsize - tail); + KUNIT_ASSERT_LE(test, data->sgt->nents, data->npages); + + i += extract_iter_to_sg(iter, tail, data->sgt, + data->npages - data->sgt->nents, 0); + KUNIT_ASSERT_EQ(test, i, bufsize); + KUNIT_ASSERT_LE(test, data->sgt->nents, data->npages); + + sg_mark_end(&data->sgt->sgl[data->sgt->nents - 1]); + + i = sg_copy_to_buffer(data->sgt->sgl, data->sgt->nents, + data->scratch, bufsize); + KUNIT_ASSERT_EQ(test, i, bufsize); + + for (i = 0; i < bufsize; ++i) { + KUNIT_EXPECT_EQ_MSG(test, data->scratch[i], pattern(i), + "at i=%zx", i); + if (data->scratch[i] != pattern(i)) + break; + } + + KUNIT_EXPECT_EQ(test, i, bufsize); +} + +static void __init iov_kunit_iter_to_sg_kvec(struct kunit *test) +{ + struct iov_kunit_iter_to_sg_data data; + struct iov_iter iter; + struct kvec kvec; + size_t bufsize; + + bufsize = 0x100000; + iov_kunit_iter_to_sg_init(test, bufsize, false, &data); + + kvec.iov_base = data.buffer; + kvec.iov_len = bufsize; + iov_iter_kvec(&iter, READ, &kvec, 1, bufsize); + + iov_kunit_iter_to_sg_check(test, &iter, bufsize, &data); +} + +static void __init iov_kunit_iter_to_sg_bvec(struct kunit *test) +{ + struct iov_kunit_iter_to_sg_data data; + struct page *p, *can_merge = NULL; + size_t i, k, bufsize; + struct bio_vec *bvec; + struct iov_iter iter; + + bufsize = 0x100000; + iov_kunit_iter_to_sg_init(test, bufsize, false, &data); + + bvec = kunit_kmalloc_array(test, data.npages, sizeof(*bvec), + GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bvec); + k = 0; + for (i = 0; i < data.npages; ++i) { + p = data.pages[i]; + if (p == can_merge) + bvec[k-1].bv_len += PAGE_SIZE; + else + bvec_set_page(&bvec[k++], p, PAGE_SIZE, 0); + can_merge = p + 1; + } + iov_iter_bvec(&iter, READ, bvec, k, bufsize); + + iov_kunit_iter_to_sg_check(test, &iter, bufsize, &data); +} + +static void __init iov_kunit_iter_to_sg_folioq(struct kunit *test) +{ + struct iov_kunit_iter_to_sg_data data; + struct folio_queue *folioq; + struct iov_iter iter; + size_t bufsize; + + bufsize = 0x100000; + iov_kunit_iter_to_sg_init(test, bufsize, false, &data); + + folioq = iov_kunit_create_folioq(test); + iov_kunit_load_folioq(test, &iter, READ, folioq, data.pages, + data.npages); + + iov_kunit_iter_to_sg_check(test, &iter, bufsize, &data); +} + +static void __init iov_kunit_iter_to_sg_xarray(struct kunit *test) +{ + struct iov_kunit_iter_to_sg_data data; + struct xarray *xarray; + struct iov_iter iter; + size_t bufsize; + + bufsize = 0x100000; + iov_kunit_iter_to_sg_init(test, bufsize, false, &data); + + xarray = iov_kunit_create_xarray(test); + iov_kunit_load_xarray(test, &iter, READ, xarray, data.pages, + data.npages); + + iov_kunit_iter_to_sg_check(test, &iter, bufsize, &data); +} + +static void __init iov_kunit_iter_to_sg_ubuf(struct kunit *test) +{ + struct iov_kunit_iter_to_sg_data data; + struct iov_iter iter; + size_t bufsize; + + bufsize = 0x100000; + iov_kunit_iter_to_sg_init(test, bufsize, true, &data); + + iov_iter_ubuf(&iter, READ, data.ubuf, bufsize); + + iov_kunit_iter_to_sg_check(test, &iter, bufsize, &data); +} + static struct kunit_case __refdata iov_kunit_cases[] = { KUNIT_CASE(iov_kunit_copy_to_kvec), KUNIT_CASE(iov_kunit_copy_from_kvec), @@ -1029,6 +1227,11 @@ static struct kunit_case __refdata iov_kunit_cases[] = { KUNIT_CASE(iov_kunit_extract_pages_bvec), KUNIT_CASE(iov_kunit_extract_pages_folioq), KUNIT_CASE(iov_kunit_extract_pages_xarray), + KUNIT_CASE(iov_kunit_iter_to_sg_kvec), + KUNIT_CASE(iov_kunit_iter_to_sg_bvec), + KUNIT_CASE(iov_kunit_iter_to_sg_folioq), + KUNIT_CASE(iov_kunit_iter_to_sg_xarray), + KUNIT_CASE(iov_kunit_iter_to_sg_ubuf), {} };