diff options
Diffstat (limited to 'kernel/compat.c')
-rw-r--r-- | kernel/compat.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/kernel/compat.c b/kernel/compat.c index 5adab05a3172..c9e2ec0b34a8 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -279,11 +279,6 @@ asmlinkage long compat_sys_setrlimit(unsigned int resource, struct compat_rlimit __user *rlim) { struct rlimit r; - int ret; - mm_segment_t old_fs = get_fs (); - - if (resource >= RLIM_NLIMITS) - return -EINVAL; if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) || __get_user(r.rlim_cur, &rlim->rlim_cur) || @@ -294,10 +289,7 @@ asmlinkage long compat_sys_setrlimit(unsigned int resource, r.rlim_cur = RLIM_INFINITY; if (r.rlim_max == COMPAT_RLIM_INFINITY) r.rlim_max = RLIM_INFINITY; - set_fs(KERNEL_DS); - ret = sys_setrlimit(resource, (struct rlimit __user *) &r); - set_fs(old_fs); - return ret; + return do_prlimit(current, resource, &r, NULL); } #ifdef COMPAT_RLIM_OLD_INFINITY @@ -329,16 +321,13 @@ asmlinkage long compat_sys_old_getrlimit(unsigned int resource, #endif -asmlinkage long compat_sys_getrlimit (unsigned int resource, +asmlinkage long compat_sys_getrlimit(unsigned int resource, struct compat_rlimit __user *rlim) { struct rlimit r; int ret; - mm_segment_t old_fs = get_fs(); - set_fs(KERNEL_DS); - ret = sys_getrlimit(resource, (struct rlimit __user *) &r); - set_fs(old_fs); + ret = do_prlimit(current, resource, NULL, &r); if (!ret) { if (r.rlim_cur > COMPAT_RLIM_INFINITY) r.rlim_cur = COMPAT_RLIM_INFINITY; @@ -1137,3 +1126,24 @@ compat_sys_sysinfo(struct compat_sysinfo __user *info) return 0; } + +/* + * Allocate user-space memory for the duration of a single system call, + * in order to marshall parameters inside a compat thunk. + */ +void __user *compat_alloc_user_space(unsigned long len) +{ + void __user *ptr; + + /* If len would occupy more than half of the entire compat space... */ + if (unlikely(len > (((compat_uptr_t)~0) >> 1))) + return NULL; + + ptr = arch_compat_alloc_user_space(len); + + if (unlikely(!access_ok(VERIFY_WRITE, ptr, len))) + return NULL; + + return ptr; +} +EXPORT_SYMBOL_GPL(compat_alloc_user_space); |