linux-kernel - [v5 4/6] extable: Add function to search only kernel exception table

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: <20190709121524.18762-5-santosh@fossix.org>
Date:   Tue,  9 Jul 2019 17:45:22 +0530
From:   Santosh Sivaraj <santosh@...six.org>
To:     linuxppc-dev <linuxppc-dev@...ts.ozlabs.org>,
        linux-kernel@...r.kernel.org
Cc:     "Aneesh Kumar K.V" <aneesh.kumar@...ux.ibm.com>,
        Mahesh Salgaonkar <mahesh@...ux.ibm.com>,
        Reza Arbab <arbab@...ux.ibm.com>,
        Balbir Singh <bsingharora@...il.com>,
        Chandan Rajendra <chandan@...ux.vnet.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Nicholas Piggin <npiggin@...il.com>,
        christophe leroy <christophe.leroy@....fr>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...nel.org>
Subject: [v5 4/6] extable: Add function to search only kernel exception table

In real mode, the search_exception tables cannot be called because
it also searches the module exception tables if entry is not found
in the kernel exception tables.

Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Ingo Molnar <mingo@...nel.org>
Cc: Nicholas Piggin <npiggin@...il.com>
Signed-off-by: Santosh Sivaraj <santosh@...six.org>
---
 include/linux/extable.h |  2 ++
 kernel/extable.c        | 16 +++++++++++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/include/linux/extable.h b/include/linux/extable.h
index 41c5b3a25f67..0c2819ba67f0 100644
--- a/include/linux/extable.h
+++ b/include/linux/extable.h
@@ -19,6 +19,8 @@ void trim_init_extable(struct module *m);
 
 /* Given an address, look for it in the exception tables */
 const struct exception_table_entry *search_exception_tables(unsigned long add);
+const struct
+exception_table_entry *search_kernel_exception_table(unsigned long addr);
 
 #ifdef CONFIG_MODULES
 /* For extable.c to search modules' exception tables. */
diff --git a/kernel/extable.c b/kernel/extable.c
index e23cce6e6092..6d544cb79fff 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -40,13 +40,23 @@ void __init sort_main_extable(void)
 	}
 }
 
-/* Given an address, look for it in the exception tables. */
+/* For the given address, look for it in the kernel exception table */
+const
+struct exception_table_entry *search_kernel_exception_table(unsigned long addr)
+{
+	return search_extable(__start___ex_table,
+			      __stop___ex_table - __start___ex_table, addr);
+}
+
+/*
+ * Given an address, look for it in the kernel and the module exception
+ * tables.
+ */
 const struct exception_table_entry *search_exception_tables(unsigned long addr)
 {
 	const struct exception_table_entry *e;
 
-	e = search_extable(__start___ex_table,
-			   __stop___ex_table - __start___ex_table, addr);
+	e = search_kernel_exception_table(addr);
 	if (!e)
 		e = search_module_extables(addr);
 	return e;
-- 
2.20.1