linux-kernel - [REVIEW][PATCH 7/9] signal/poewrpc: Specialize _exception

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: <20180918175850.4437-7-ebiederm@xmission.com>
Date:   Tue, 18 Sep 2018 19:58:48 +0200
From:   "Eric W. Biederman" <ebiederm@...ssion.com>
To:     linux-kernel@...r.kernel.org
Cc:     linux-arch@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>,
        "Eric W. Biederman" <ebiederm@...ssion.com>
Subject: [REVIEW][PATCH 7/9] signal/poewrpc: Specialize _exception_pkey for handling pkey exceptions

Now that _exception no longer calls _exception_pkey it is no longer
necessary to handle any signal with any si_code.  All pkey exceptions
are SIGSEGV with paired with SEGV_PKUERR.  So just handle
that case and remove the now unnecessary parameters from _exception_pkey.

Signed-off-by: "Eric W. Biederman" <ebiederm@...ssion.com>
---
 arch/powerpc/include/asm/bug.h |  2 +-
 arch/powerpc/kernel/traps.c    | 10 +++++-----
 arch/powerpc/mm/fault.c        |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h
index fd06dbe7d7d3..fed7e6241349 100644
--- a/arch/powerpc/include/asm/bug.h
+++ b/arch/powerpc/include/asm/bug.h
@@ -133,7 +133,7 @@ struct pt_regs;
 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 extern void _exception(int, struct pt_regs *, int, unsigned long);
-extern void _exception_pkey(int, struct pt_regs *, int, unsigned long, int);
+extern void _exception_pkey(struct pt_regs *, unsigned long, int);
 extern void die(const char *, struct pt_regs *, long);
 extern bool die_will_crash(void);
 extern void panic_flush_kmsg_start(void);
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index c38bec51dd84..e5ea69222459 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -362,20 +362,20 @@ static bool exception_common(int signr, struct pt_regs *regs, int code,
 	return true;
 }
 
-void _exception_pkey(int signr, struct pt_regs *regs, int code, unsigned long addr, int key)
+void _exception_pkey(struct pt_regs *regs, unsigned long addr, int key)
 {
 	siginfo_t info;
 
-	if (!exception_common(signr, regs, code, addr))
+	if (!exception_common(SIGSEGV, regs, SEGV_PKUERR, addr))
 		return;
 
 	clear_siginfo(&info);
-	info.si_signo = signr;
-	info.si_code = code;
+	info.si_signo = SIGSEGV;
+	info.si_code = SEGV_PKUERR;
 	info.si_addr = (void __user *) addr;
 	info.si_pkey = key;
 
-	force_sig_info(signr, &info, current);
+	force_sig_info(info.si_signo, &info, current);
 }
 
 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index a84d06b7d50d..406d0e0ef096 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -152,7 +152,7 @@ static int bad_key_fault_exception(struct pt_regs *regs, unsigned long address,
 	if (!user_mode(regs))
 		return SIGSEGV;
 
-	_exception_pkey(SIGSEGV, regs, SEGV_PKUERR, address, pkey);
+	_exception_pkey(regs, address, pkey);
 
 	return 0;
 }
-- 
2.17.1