linux-kernel - [PATCH 4.9 194/240] ARM: 9064/1: hw_breakpoint: Do not directly check the events overflow

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: <20210520092115.177668376@linuxfoundation.org>
Date:   Thu, 20 May 2021 11:23:06 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Zhen Lei <thunder.leizhen@...wei.com>,
        Wang Nan <wangnan0@...wei.com>, Will Deacon <will@...nel.org>,
        Russell King <rmk+kernel@...linux.org.uk>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.9 194/240] ARM: 9064/1: hw_breakpoint: Do not directly check the events overflow_handler hook

From: Zhen Lei <thunder.leizhen@...wei.com>

[ Upstream commit a506bd5756290821a4314f502b4bafc2afcf5260 ]

The commit 1879445dfa7b ("perf/core: Set event's default
::overflow_handler()") set a default event->overflow_handler in
perf_event_alloc(), and replace the check event->overflow_handler with
is_default_overflow_handler(), but one is missing.

Currently, the bp->overflow_handler can not be NULL. As a result,
enable_single_step() is always not invoked.

Comments from Zhen Lei:

 https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210207105934.2001-1-thunder.leizhen@huawei.com/

Fixes: 1879445dfa7b ("perf/core: Set event's default ::overflow_handler()")
Signed-off-by: Zhen Lei <thunder.leizhen@...wei.com>
Cc: Wang Nan <wangnan0@...wei.com>
Acked-by: Will Deacon <will@...nel.org>
Signed-off-by: Russell King <rmk+kernel@...linux.org.uk>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/arm/kernel/hw_breakpoint.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 671dbc28e5d4..59e04e2d9d9d 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -891,7 +891,7 @@ static void breakpoint_handler(unsigned long unknown, struct pt_regs *regs)
 			info->trigger = addr;
 			pr_debug("breakpoint fired: address = 0x%x\n", addr);
 			perf_bp_event(bp, regs);
-			if (!bp->overflow_handler)
+			if (is_default_overflow_handler(bp))
 				enable_single_step(bp, addr);
 			goto unlock;
 		}
-- 
2.30.2