linux-kernel - [PATCH v2 2/5] m68k: Replace NR_syscalls macro from asm/unistd.h

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: <1537455973-12468-3-git-send-email-firoz.khan@linaro.org>
Date:   Thu, 20 Sep 2018 20:36:10 +0530
From:   Firoz Khan <firoz.khan@...aro.org>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>,
        linux-m68k@...ts.linux-m68k.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Philippe Ombredanne <pombredanne@...b.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Kate Stewart <kstewart@...uxfoundation.org>
Cc:     y2038@...ts.linaro.org, linux-kernel@...r.kernel.org,
        linux-arch@...r.kernel.org, arnd@...db.de, deepa.kernel@...il.com,
        marcin.juszkiewicz@...aro.org, firoz.khan@...aro.org
Subject: [PATCH v2 2/5] m68k: Replace NR_syscalls macro from asm/unistd.h

NR_syscalls macro holds the number of system call exist in m68k
architecture. This macro is currently the part of asm/unistd.h file.
We have to change the value of NR_syscalls, if we add or delete a
system call.

One of patch in this patch series has a script which will generate
a uapi header based on syscall.tbl file. The syscall.tbl file
contains the number of system call information. So we have two
option to update NR_syscalls value.

1. Update NR_syscalls in asm/unistd.h manually by counting the
   no.of system calls. No need to update NR_syscalls untill
   we either add a new system call or delete an existing system
   call.

2. We can keep this feature it above mentioned script, that'll
   count the number of syscalls and keep it in a generated file.
   In this case we don't need to explicitly update NR_syscalls
   in asm/unistd.h file.

The 2nd option will be the recommended one. For that, I come up
with another macro - __NR_syscalls which will be updated by the
script and it will be present in api/asm/unistd.h. While __NR_syscalls
isn't strictly part of the uapi, having it as part of the generated
header to simplifies the implementation. So we need to enclose this
macro with #ifdef __KERNEL__ to avoid side effects.

Signed-off-by: Firoz Khan <firoz.khan@...aro.org>
---
 arch/m68k/include/asm/unistd.h      | 3 +--
 arch/m68k/include/uapi/asm/unistd.h | 4 ++++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/m68k/include/asm/unistd.h b/arch/m68k/include/asm/unistd.h
index 30d0d3f..5072e94 100644
--- a/arch/m68k/include/asm/unistd.h
+++ b/arch/m68k/include/asm/unistd.h
@@ -4,8 +4,7 @@

 #include <uapi/asm/unistd.h>

-
-#define NR_syscalls		380
+#define NR_syscalls __NR_syscalls

 #define __ARCH_WANT_OLD_READDIR
 #define __ARCH_WANT_OLD_STAT
diff --git a/arch/m68k/include/uapi/asm/unistd.h b/arch/m68k/include/uapi/asm/unistd.h
index de3054f..ba4176aa 100644
--- a/arch/m68k/include/uapi/asm/unistd.h
+++ b/arch/m68k/include/uapi/asm/unistd.h
@@ -387,4 +387,8 @@
 #define __NR_pwritev2		378
 #define __NR_statx		379

+#ifdef __KERNEL__
+#define __NR_syscalls		380
+#endif
+
 #endif /* _UAPI_ASM_M68K_UNISTD_H_ */
-- 
1.9.1