From c90012ac85c24547e5c3468ef00aabf44aa7332d Mon Sep 17 00:00:00 2001 From: Aleksa Sarai Date: Sun, 6 Oct 2019 10:30:28 +1100 Subject: [PATCH] lib: test_user_copy: style cleanup While writing the tests for copy_struct_from_user(), I used a construct that Linus doesn't appear to be too fond of: On 2019-10-04, Linus Torvalds wrote: > Hmm. That code is ugly, both before and after the fix. > > This just doesn't make sense for so many reasons: > > if ((ret |= test(umem_src == NULL, "kmalloc failed"))) > > where the insanity comes from > > - why "|=" when you know that "ret" was zero before (and it had to > be, for the test to make sense) > > - why do this as a single line anyway? > > - don't do the stupid "double parenthesis" to hide a warning. Make it > use an actual comparison if you add a layer of parentheses. So instead, use a bog-standard check that isn't nearly as ugly. Fixes: 341115822f88 ("usercopy: Add parentheses around assignment in test_copy_struct_from_user") Fixes: f5a1a536fa14 ("lib: introduce copy_struct_from_user() helper") Signed-off-by: Aleksa Sarai Reviewed-by: Nathan Chancellor Reviewed-by: Christian Brauner Link: https://lore.kernel.org/r/20191005233028.18566-1-cyphar@cyphar.com Signed-off-by: Christian Brauner --- lib/test_user_copy.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c index e365ace06538..ad2372727b1b 100644 --- a/lib/test_user_copy.c +++ b/lib/test_user_copy.c @@ -52,13 +52,14 @@ static int test_check_nonzero_user(char *kmem, char __user *umem, size_t size) size_t zero_end = size - zero_start; /* - * We conduct a series of check_nonzero_user() tests on a block of memory - * with the following byte-pattern (trying every possible [start,end] - * pair): + * We conduct a series of check_nonzero_user() tests on a block of + * memory with the following byte-pattern (trying every possible + * [start,end] pair): * * [ 00 ff 00 ff ... 00 00 00 00 ... ff 00 ff 00 ] * - * And we verify that check_nonzero_user() acts identically to memchr_inv(). + * And we verify that check_nonzero_user() acts identically to + * memchr_inv(). */ memset(kmem, 0x0, size); @@ -93,11 +94,13 @@ static int test_copy_struct_from_user(char *kmem, char __user *umem, size_t ksize, usize; umem_src = kmalloc(size, GFP_KERNEL); - if ((ret |= test(umem_src == NULL, "kmalloc failed"))) + ret = test(umem_src == NULL, "kmalloc failed"); + if (ret) goto out_free; expected = kmalloc(size, GFP_KERNEL); - if ((ret |= test(expected == NULL, "kmalloc failed"))) + ret = test(expected == NULL, "kmalloc failed"); + if (ret) goto out_free; /* Fill umem with a fixed byte pattern. */