Hi Li, Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master] [also build test ERROR on v4.17-rc1 next-20180418] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Li-Bin/prctl-fix-compat-handling-for-prctl/20180419-004502 config: x86_64-randconfig-x002-201815 (attached as .config) compiler: gcc-7 (Debian 7.3.0-16) 7.3.0 reproduce: # save the attached .config to linux build tree make ARCH=x86_64 All errors (new ones prefixed by >>): kernel/sys.c: In function 'prctl_set_mm_map': >> kernel/sys.c:2009:6: error: implicit declaration of function >> 'is_compat_task'; did you mean 'is_idle_task'? >> [-Werror=implicit-function-declaration] if (is_compat_task()) { ^~~~~~~~~~~~~~ is_idle_task cc1: some warnings being treated as errors vim +2009 kernel/sys.c 1989 1990 #ifdef CONFIG_CHECKPOINT_RESTORE 1991 static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) 1992 { 1993 struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; 1994 unsigned long user_auxv[AT_VECTOR_SIZE]; 1995 struct mm_struct *mm = current->mm; 1996 int error; 1997 1998 BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); 1999 BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256); 2000 2001 if (opt == PR_SET_MM_MAP_SIZE) 2002 return put_user((unsigned int)sizeof(prctl_map), 2003 (unsigned int __user *)addr); 2004 2005 if (data_size != sizeof(prctl_map)) 2006 return -EINVAL; 2007 2008 #ifdef CONFIG_COMPAT > 2009 if (is_compat_task()) { 2010 struct compat_prctl_mm_map prctl_map32; 2011 if (copy_from_user(&prctl_map32, addr, sizeof(prctl_map32))) 2012 return -EFAULT; 2013 2014 prctl_map.start_code = prctl_map32.start_code; 2015 prctl_map.end_code = prctl_map32.end_code; 2016 prctl_map.start_data = prctl_map32.start_data; 2017 prctl_map.end_data = prctl_map32.end_data; 2018 prctl_map.start_brk = prctl_map32.start_brk; 2019 prctl_map.brk = prctl_map32.brk; 2020 prctl_map.start_stack = prctl_map32.start_stack; 2021 prctl_map.arg_start = prctl_map32.arg_start; 2022 prctl_map.arg_end = prctl_map32.arg_end; 2023 prctl_map.env_start = prctl_map32.env_start; 2024 prctl_map.env_end = prctl_map32.env_end; 2025 prctl_map.auxv = compat_ptr(prctl_map32.auxv); 2026 prctl_map.auxv_size = prctl_map32.auxv_size; 2027 prctl_map.exe_fd = prctl_map32.exe_fd; 2028 } else 2029 #endif 2030 if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) 2031 return -EFAULT; 2032 2033 error = validate_prctl_map(&prctl_map); 2034 if (error) 2035 return error; 2036 2037 if (prctl_map.auxv_size) { 2038 memset(user_auxv, 0, sizeof(user_auxv)); 2039 if (copy_from_user(user_auxv, 2040 (const void __user *)prctl_map.auxv, 2041 prctl_map.auxv_size)) 2042 return -EFAULT; 2043 2044 /* Last entry must be AT_NULL as specification requires */ 2045 user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL; 2046 user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL; 2047 } 2048 2049 if (prctl_map.exe_fd != (u32)-1) { 2050 error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd); 2051 if (error) 2052 return error; 2053 } 2054 2055 down_write(&mm->mmap_sem); 2056 2057 /* 2058 * We don't validate if these members are pointing to 2059 * real present VMAs because application may have correspond 2060 * VMAs already unmapped and kernel uses these members for statistics 2061 * output in procfs mostly, except 2062 * 2063 * - @start_brk/@brk which are used in do_brk but kernel lookups 2064 * for VMAs when updating these memvers so anything wrong written 2065 * here cause kernel to swear at userspace program but won't lead 2066 * to any problem in kernel itself 2067 */ 2068 2069 mm->start_code = prctl_map.start_code; 2070 mm->end_code = prctl_map.end_code; 2071 mm->start_data = prctl_map.start_data; 2072 mm->end_data = prctl_map.end_data; 2073 mm->start_brk = prctl_map.start_brk; 2074 mm->brk = prctl_map.brk; 2075 mm->start_stack = prctl_map.start_stack; 2076 mm->arg_start = prctl_map.arg_start; 2077 mm->arg_end = prctl_map.arg_end; 2078 mm->env_start = prctl_map.env_start; 2079 mm->env_end = prctl_map.env_end; 2080 2081 /* 2082 * Note this update of @saved_auxv is lockless thus 2083 * if someone reads this member in procfs while we're 2084 * updating -- it may get partly updated results. It's 2085 * known and acceptable trade off: we leave it as is to 2086 * not introduce additional locks here making the kernel 2087 * more complex. 2088 */ 2089 if (prctl_map.auxv_size) 2090 memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv)); 2091 2092 up_write(&mm->mmap_sem); 2093 return 0; 2094 } 2095 #endif /* CONFIG_CHECKPOINT_RESTORE */ 2096 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
.config.gz
Description: application/gzip
