[NET]: Fix sock_fprog setsockopt compat handling. Based upon patch from Andi Kleen.

arch/ppc64/kernel/ioctl32.c

@@ -672,21 +672,6 @@ static int bond_ioctl(unsigned long fd, unsigned int cmd, unsigned long arg)
 	return err;
 }
 
-static inline void *alloc_user_space(long len)
-{
-	struct pt_regs *regs = current->thread.regs;
-	unsigned long usp = regs->gpr[1];
-
-	/*
-	 * We cant access below the stack pointer in the 32bit ABI and
-	 * can access 288 bytes in the 64bit ABI
-	 */
-	if (!(test_thread_flag(TIF_32BIT)))
-		usp -= 288;
-
-	return (void *) (usp - len);
-}
-
 int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
 	struct ifreq *u_ifreq64;
@@ -702,7 +687,7 @@ int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 		return -EFAULT;
 	data64 = A(data32);
 
-	u_ifreq64 = alloc_user_space(sizeof(*u_ifreq64));
+	u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
 
 	/* Don't check these user accesses, just let that get trapped
 	 * in the ioctl handler instead.

arch/sparc64/kernel/ioctl32.c

@@ -659,17 +659,6 @@ static int bond_ioctl(unsigned long fd, unsigned int cmd, unsigned long arg)
 	return err;
 }
 
-static __inline__ void *alloc_user_space(long len)
-{
-	struct pt_regs *regs = current_thread_info()->kregs;
-	unsigned long usp = regs->u_regs[UREG_I6];
-
-	if (!(test_thread_flag(TIF_32BIT)))
-		usp += STACK_BIAS;
-
-	return (void *) (usp - len);
-}
-
 int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
 	struct ifreq *u_ifreq64;
@@ -685,7 +674,7 @@ int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 		return -EFAULT;
 	data64 = A(data32);
 
-	u_ifreq64 = alloc_user_space(sizeof(*u_ifreq64));
+	u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
 
 	/* Don't check these user accesses, just let that get trapped
 	 * in the ioctl handler instead.
@@ -1701,7 +1690,7 @@ struct sock_fprog32 {
 static int ppp_sock_fprog_ioctl_trans(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
 	struct sock_fprog32 *u_fprog32 = (struct sock_fprog32 *) arg;
-	struct sock_fprog *u_fprog64 = alloc_user_space(sizeof(struct sock_fprog));
+	struct sock_fprog *u_fprog64 = compat_alloc_user_space(sizeof(struct sock_fprog));
 	void __user *fptr64;
 	u32 fptr32;
 	u16 flen;

arch/x86_64/ia32/ia32_ioctl.c

@@ -671,12 +671,6 @@ static int bond_ioctl(unsigned long fd, unsigned int cmd, unsigned long arg)
 	return err;
 }
 
-static __inline__ void *alloc_user_space(long len)
-{
-	struct pt_regs *regs = (void *)current->thread.rsp0 - sizeof(struct pt_regs); 
-	return (void *)regs->rsp - len; 
-}
-
 int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
 	struct ifreq *u_ifreq64;
@@ -692,7 +686,7 @@ int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 		return -EFAULT;
 	data64 = (void *) A(data32);
 
-	u_ifreq64 = alloc_user_space(sizeof(*u_ifreq64));
+	u_ifreq64 = compat_alloc_user_space(sizeof(*u_ifreq64));
 
 	/* Don't check these user accesses, just let that get trapped
 	 * in the ioctl handler instead.
@@ -1573,7 +1567,7 @@ struct sock_fprog32 {
 static int ppp_sock_fprog_ioctl_trans(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
 	struct sock_fprog32 *u_fprog32 = (struct sock_fprog32 *) arg;
-	struct sock_fprog *u_fprog64 = alloc_user_space(sizeof(struct sock_fprog));
+	struct sock_fprog *u_fprog64 = compat_alloc_user_space(sizeof(struct sock_fprog));
 	void *fptr64;
 	u32 fptr32;
 	u16 flen;

include/asm-ppc64/compat.h

@@ -119,4 +119,19 @@ static inline void *compat_ptr(compat_uptr_t uptr)
 	return (void *)(unsigned long)uptr;
 }
 
+static inline void *compat_alloc_user_space(long len)
+{
+	struct pt_regs *regs = current->thread.regs;
+	unsigned long usp = regs->gpr[1];
+
+	/*
+	 * We cant access below the stack pointer in the 32bit ABI and
+	 * can access 288 bytes in the 64bit ABI
+	 */
+	if (!(test_thread_flag(TIF_32BIT)))
+		usp -= 288;
+
+	return (void *) (usp - len);
+}
+
 #endif /* _ASM_PPC64_COMPAT_H */

include/asm-sparc64/compat.h

@@ -120,4 +120,15 @@ static inline void *compat_ptr(compat_uptr_t uptr)
 	return (void *)(unsigned long)uptr;
 }
 
+static __inline__ void *compat_alloc_user_space(long len)
+{
+	struct pt_regs *regs = current_thread_info()->kregs;
+	unsigned long usp = regs->u_regs[UREG_I6];
+
+	if (!(test_thread_flag(TIF_32BIT)))
+		usp += STACK_BIAS;
+
+	return (void *) (usp - len);
+}
+
 #endif /* _ASM_SPARC64_COMPAT_H */

include/asm-x86_64/compat.h

@@ -128,4 +128,10 @@ static inline void *compat_ptr(compat_uptr_t uptr)
 	return (void *)(unsigned long)uptr;
 }
 
+static __inline__ void *compat_alloc_user_space(long len)
+{
+	struct pt_regs *regs = (void *)current->thread.rsp0 - sizeof(struct pt_regs); 
+	return (void *)regs->rsp - len; 
+}
+
 #endif /* _ASM_X86_64_COMPAT_H */

net/compat.c

@@ -389,30 +389,20 @@ static int do_set_attach_filter(int fd, int level, int optname,
 				char *optval, int optlen)
 {
 	struct compat_sock_fprog *fprog32 = (struct compat_sock_fprog *)optval;
-	struct sock_fprog kfprog;
-	mm_segment_t old_fs;
-	int ret;
+	struct sock_fprog *kfprog = compat_alloc_user_space(sizeof(struct sock_fprog)); 
 	compat_uptr_t ptr;
+	u16 len;
 
 	if (!access_ok(VERIFY_READ, fprog32, sizeof(*fprog32)) ||
-	    __get_user(kfprog.len, &fprog32->len) ||
-	    __get_user(ptr, &fprog32->filter))
-		return -EFAULT;
-	kfprog.filter = compat_ptr(ptr);	
-
-	if (kfprog.len * sizeof(struct sock_filter) < kfprog.len) 
-		return -EINVAL;
-
-	if (verify_area(VERIFY_READ, kfprog.filter, 
-				    kfprog.len * sizeof(struct sock_filter)))
+	    !access_ok(VERIFY_WRITE, kfprog, sizeof(struct sock_fprog)) ||
+	    __get_user(len, &fprog32->len) ||
+	    __get_user(ptr, &fprog32->filter) ||
+	    __put_user(len, &kfprog->len) ||
+	    __put_user(compat_ptr(ptr), &kfprog->filter))
 		return -EFAULT;
 
-	old_fs = get_fs();
-	set_fs(KERNEL_DS);
-	ret = sys_setsockopt(fd, level, optname,
-			     (char *)&kfprog, sizeof(kfprog));
-	set_fs(old_fs);
-	return ret;
+	return sys_setsockopt(fd, level, optname, (char *)kfprog, 
+			      sizeof(struct sock_fprog));
 }
 
 static int do_set_icmpv6_filter(int fd, int level, int optname,