From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752846AbeDSBQQ (ORCPT ); Wed, 18 Apr 2018 21:16:16 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:40338 "EHLO huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752738AbeDSBQP (ORCPT ); Wed, 18 Apr 2018 21:16:15 -0400 From: Li Bin To: Al Viro , "Eric W. Biederman" , Dominik Brodowski , Andrew Morton , Andy Lutomirski , CC: , Subject: [PATCH v2] prctl: fix compat handling for prctl Date: Thu, 19 Apr 2018 09:06:06 +0800 Message-ID: <1524099966-43544-1-git-send-email-huawei.libin@huawei.com> X-Mailer: git-send-email 1.7.12.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The member auxv in prctl_mm_map structure which be shared with userspace is pointer type, but the kernel supporting COMPAT didn't handle it. This patch fix the compat handling for prctl syscall. Signed-off-by: Li Bin --- kernel/sys.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/kernel/sys.c b/kernel/sys.c index ad69218..d4259938 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1969,6 +1969,26 @@ static int validate_prctl_map(struct prctl_mm_map *prctl_map) } #ifdef CONFIG_CHECKPOINT_RESTORE + +#ifdef CONFIG_COMPAT +struct compat_prctl_mm_map { + __u64 start_code; /* code section bounds */ + __u64 end_code; + __u64 start_data; /* data section bounds */ + __u64 end_data; + __u64 start_brk; /* heap for brk() syscall */ + __u64 brk; + __u64 start_stack; /* stack starts at */ + __u64 arg_start; /* command line arguments bounds */ + __u64 arg_end; + __u64 env_start; /* environment variables bounds */ + __u64 env_end; + compat_uptr_t auxv; /* auxiliary vector */ + __u32 auxv_size; /* vector size */ + __u32 exe_fd; /* /proc/$pid/exe link file */ +}; +#endif + static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) { struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; @@ -1986,6 +2006,28 @@ static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data if (data_size != sizeof(prctl_map)) return -EINVAL; +#ifdef CONFIG_COMPAT + if (in_compat_syscall()) { + struct compat_prctl_mm_map prctl_map32; + if (copy_from_user(&prctl_map32, addr, sizeof(prctl_map32))) + return -EFAULT; + + prctl_map.start_code = prctl_map32.start_code; + prctl_map.end_code = prctl_map32.end_code; + prctl_map.start_data = prctl_map32.start_data; + prctl_map.end_data = prctl_map32.end_data; + prctl_map.start_brk = prctl_map32.start_brk; + prctl_map.brk = prctl_map32.brk; + prctl_map.start_stack = prctl_map32.start_stack; + prctl_map.arg_start = prctl_map32.arg_start; + prctl_map.arg_end = prctl_map32.arg_end; + prctl_map.env_start = prctl_map32.env_start; + prctl_map.env_end = prctl_map32.env_end; + prctl_map.auxv = compat_ptr(prctl_map32.auxv); + prctl_map.auxv_size = prctl_map32.auxv_size; + prctl_map.exe_fd = prctl_map32.exe_fd; + } else +#endif if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) return -EFAULT; -- 1.7.12.4