lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20221217001058.41426-2-sashal@kernel.org>
Date:   Fri, 16 Dec 2022 19:10:54 -0500
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Mark Rutland <mark.rutland@....com>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>, Sasha Levin <sashal@...nel.org>,
        broonie@...nel.org, keescook@...omium.org,
        wangkefeng.wang@...wei.com, flaniel@...ux.microsoft.com,
        christophe.leroy@...roup.eu, linux-arm-kernel@...ts.infradead.org
Subject: [PATCH AUTOSEL 5.10 2/5] arm64: make is_ttbrX_addr() noinstr-safe

From: Mark Rutland <mark.rutland@....com>

[ Upstream commit d8c1d798a2e5091128c391c6dadcc9be334af3f5 ]

We use is_ttbr0_addr() in noinstr code, but as it's only marked as
inline, it's theoretically possible for the compiler to place it
out-of-line and instrument it, which would be problematic.

Mark is_ttbr0_addr() as __always_inline such that that can safely be
used from noinstr code. For consistency, do the same to is_ttbr1_addr().
Note that while is_ttbr1_addr() calls arch_kasan_reset_tag(), this is a
macro (and its callees are either macros or __always_inline), so there
is not a risk of transient instrumentation.

Signed-off-by: Mark Rutland <mark.rutland@....com>
Cc: Catalin Marinas <catalin.marinas@....com>
Cc: Will Deacon <will@...nel.org>
Link: https://lore.kernel.org/r/20221114144042.3001140-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/arm64/include/asm/processor.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 7c546c3487c9..c628d8e3a403 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -230,13 +230,13 @@ static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
 }
 #endif
 
-static inline bool is_ttbr0_addr(unsigned long addr)
+static __always_inline bool is_ttbr0_addr(unsigned long addr)
 {
 	/* entry assembly clears tags for TTBR0 addrs */
 	return addr < TASK_SIZE;
 }
 
-static inline bool is_ttbr1_addr(unsigned long addr)
+static __always_inline bool is_ttbr1_addr(unsigned long addr)
 {
 	/* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */
 	return arch_kasan_reset_tag(addr) >= PAGE_OFFSET;
-- 
2.35.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ