diff options
-rw-r--r-- | arch/ia64/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/mips/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/parisc/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/powerpc/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/s390/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/sparc/include/asm/compat.h | 2 | ||||
-rw-r--r-- | arch/x86/include/asm/compat.h | 2 | ||||
-rw-r--r-- | include/linux/compat.h | 2 | ||||
-rw-r--r-- | kernel/compat.c | 22 |
9 files changed, 31 insertions, 7 deletions
diff --git a/arch/ia64/include/asm/compat.h b/arch/ia64/include/asm/compat.h index dfcf75b8426d..c8662cd40fdc 100644 --- a/arch/ia64/include/asm/compat.h +++ b/arch/ia64/include/asm/compat.h @@ -198,7 +198,7 @@ ptr_to_compat(void __user *uptr) } static __inline__ void __user * -compat_alloc_user_space (long len) +arch_compat_alloc_user_space (long len) { struct pt_regs *regs = task_pt_regs(current); return (void __user *) (((regs->r12 & 0xffffffff) & -16) - len); diff --git a/arch/mips/include/asm/compat.h b/arch/mips/include/asm/compat.h index f58aed354bfd..27505bdc386e 100644 --- a/arch/mips/include/asm/compat.h +++ b/arch/mips/include/asm/compat.h @@ -144,7 +144,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; } -static inline void __user *compat_alloc_user_space(long len) +static inline void __user *arch_compat_alloc_user_space(long len) { struct pt_regs *regs = (struct pt_regs *) ((unsigned long) current_thread_info() + THREAD_SIZE - 32) - 1; diff --git a/arch/parisc/include/asm/compat.h b/arch/parisc/include/asm/compat.h index 7f32611a7a5e..7c77fa93ab33 100644 --- a/arch/parisc/include/asm/compat.h +++ b/arch/parisc/include/asm/compat.h @@ -146,7 +146,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; } -static __inline__ void __user *compat_alloc_user_space(long len) +static __inline__ void __user *arch_compat_alloc_user_space(long len) { struct pt_regs *regs = ¤t->thread.regs; return (void __user *)regs->gr[30]; diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h index 4774c2f92232..8d0fff39cdba 100644 --- a/arch/powerpc/include/asm/compat.h +++ b/arch/powerpc/include/asm/compat.h @@ -133,7 +133,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; } -static inline void __user *compat_alloc_user_space(long len) +static inline void __user *arch_compat_alloc_user_space(long len) { struct pt_regs *regs = current->thread.regs; unsigned long usp = regs->gpr[1]; diff --git a/arch/s390/include/asm/compat.h b/arch/s390/include/asm/compat.h index 01a08020bc0e..0c940d38d6b7 100644 --- a/arch/s390/include/asm/compat.h +++ b/arch/s390/include/asm/compat.h @@ -180,7 +180,7 @@ static inline int is_compat_task(void) #endif -static inline void __user *compat_alloc_user_space(long len) +static inline void __user *arch_compat_alloc_user_space(long len) { unsigned long stack; diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h index 0e706257918f..612bb3862c6d 100644 --- a/arch/sparc/include/asm/compat.h +++ b/arch/sparc/include/asm/compat.h @@ -166,7 +166,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; } -static inline void __user *compat_alloc_user_space(long len) +static inline void __user *arch_compat_alloc_user_space(long len) { struct pt_regs *regs = current_thread_info()->kregs; unsigned long usp = regs->u_regs[UREG_I6]; diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h index 9a9c7bdc923d..c8c9a74d8ccc 100644 --- a/arch/x86/include/asm/compat.h +++ b/arch/x86/include/asm/compat.h @@ -204,7 +204,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; } -static inline void __user *compat_alloc_user_space(long len) +static inline void __user *arch_compat_alloc_user_space(long len) { struct pt_regs *regs = task_pt_regs(current); return (void __user *)regs->sp - len; diff --git a/include/linux/compat.h b/include/linux/compat.h index af931ee43dd8..cab23f2da4dc 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -309,5 +309,7 @@ asmlinkage long compat_sys_newfstatat(unsigned int dfd, char __user * filename, asmlinkage long compat_sys_openat(unsigned int dfd, const char __user *filename, int flags, int mode); +extern void __user *compat_alloc_user_space(unsigned long len); + #endif /* CONFIG_COMPAT */ #endif /* _LINUX_COMPAT_H */ diff --git a/kernel/compat.c b/kernel/compat.c index 180d1885f782..8bc557869d90 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -25,6 +25,7 @@ #include <linux/posix-timers.h> #include <linux/times.h> #include <linux/ptrace.h> +#include <linux/module.h> #include <asm/uaccess.h> @@ -1136,3 +1137,24 @@ 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); |