From: Kees Cook <keescook@chromium.org>
To: linux-kernel@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
Alexander Potapenko <glider@google.com>,
Joe Perches <joe@perches.com>, Andy Whitcroft <apw@canonical.com>,
x86@kernel.org, drbd-dev@lists.linbit.com,
linux-block@vger.kernel.org, b43-dev@lists.infradead.org,
netdev@vger.kernel.org, linux-doc@vger.kernel.org,
linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org,
linux-clk@vger.kernel.org, linux-spi@vger.kernel.org,
linux-mm@kvack.org, clang-built-linux@googlegroups.com
Subject: [PATCH v2 13/16] mm/debug_vm_pgtable: Remove uninitialized_var() usage
Date: Fri, 19 Jun 2020 20:30:07 -0700 [thread overview]
Message-ID: <20200620033007.1444705-17-keescook@chromium.org> (raw)
In-Reply-To: <20200620033007.1444705-1-keescook@chromium.org>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings (e.g.
"unused variable"). If the compiler thinks it is uninitialized, either
simply initialize the variable or make compiler changes. As a precursor
to removing[2] this[3] macro[4], just initialize this variable to NULL.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Fixes: 399145f9eb6c ("mm/debug: add tests validating architecture page table helpers")
Signed-off-by: Kees Cook <keescook@chromium.org>
---
mm/debug_vm_pgtable.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index e45623016aea..83c9e88a052a 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -307,7 +307,7 @@ static int __init debug_vm_pgtable(void)
phys_addr_t paddr;
unsigned long vaddr, pte_aligned, pmd_aligned;
unsigned long pud_aligned, p4d_aligned, pgd_aligned;
- spinlock_t *uninitialized_var(ptl);
+ spinlock_t *ptl = NULL;
pr_info("Validating architecture page table helpers\n");
prot = vm_get_page_prot(VMFLAGS);
--
2.25.1
next prev parent reply other threads:[~2020-06-20 3:31 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-20 3:29 [PATCH v2 00/16] Remove uninitialized_var() macro Kees Cook
2020-06-20 3:29 ` [PATCH v2 01/16] docs: deprecated.rst: Add uninitialized_var() Kees Cook
2020-06-22 16:59 ` Nick Desaulniers
2020-06-20 3:29 ` [PATCH v2 02/16] x86/mm/numa: Remove uninitialized_var() usage Kees Cook
2020-06-20 3:29 ` [PATCH v2 03/16] drbd: " Kees Cook
2020-06-20 3:29 ` [PATCH v2 04/16] b43: " Kees Cook
2020-06-22 17:04 ` Nick Desaulniers
2020-06-22 21:04 ` Kees Cook
2020-06-23 18:29 ` Nick Desaulniers
2020-07-15 10:37 ` Kalle Valo
2020-06-20 3:29 ` [PATCH v2 05/16] rtlwifi: rtl8192cu: " Kees Cook
2020-06-20 3:29 ` [PATCH v2 06/16] ide: " Kees Cook
2020-06-20 3:29 ` [PATCH v2 07/16] clk: st: " Kees Cook
2020-06-22 9:03 ` Stephen Boyd
2020-06-20 3:29 ` [PATCH v2 08/16] spi: davinci: " Kees Cook
2020-07-01 20:39 ` Mark Brown
2020-07-02 15:21 ` Kees Cook
2020-07-02 15:23 ` Mark Brown
2020-07-02 15:42 ` Kees Cook
2020-07-02 16:23 ` Joe Perches
2020-06-20 3:30 ` [PATCH v2 09/16] clk: spear: " Kees Cook
2020-06-22 9:03 ` Stephen Boyd
2020-06-20 3:30 ` [PATCH v2 10/16] KVM: PPC: Book3S PR: " Kees Cook
2020-06-22 17:22 ` Nick Desaulniers
2020-06-20 3:30 ` [PATCH v2 11/16] media: sur40: " Kees Cook
2020-06-22 18:39 ` Nick Desaulniers
2020-06-20 3:30 ` [PATCH v2 12/16] f2fs: Eliminate usage of uninitialized_var() macro Kees Cook
2020-06-20 3:30 ` [PATCH v2 14/16] checkpatch: Remove awareness " Kees Cook
2020-06-20 3:30 ` [PATCH v2 15/16] treewide: Remove uninitialized_var() usage Kees Cook
2020-06-20 3:30 ` [PATCH v2 16/16] compiler: Remove uninitialized_var() macro Kees Cook
2020-06-20 3:30 ` Kees Cook [this message]
2020-06-22 17:27 ` [PATCH v2 13/16] mm/debug_vm_pgtable: Remove uninitialized_var() usage Nick Desaulniers
2020-06-20 7:03 ` [PATCH v2 00/16] Remove uninitialized_var() macro Sedat Dilek
2020-06-20 15:57 ` Kees Cook
2020-06-22 9:07 ` Sedat Dilek
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