X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=fs%2Fcompat.c;h=4bf082dbc273dcf9ad8bdeac084400229e478b7b;hp=c98787536bb888969c37afed2f0a5c5409098682;hb=2425736505b1b7f7dedcbd911640cf6769c1759a;hpb=30307c69d59b14723fbf8a524847b302388c702d

diff --git a/fs/compat.c b/fs/compat.c
index c98787536bb8..4bf082dbc273 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -572,6 +572,10 @@ ssize_t compat_rw_copy_check_uvector(int type,
 	}
 	*ret_pointer = iov;
 
+	ret = -EFAULT;
+	if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
+		goto out;
+
 	/*
 	 * Single unix specification:
 	 * We should -EINVAL if an element length is not >= 0 and fitting an
@@ -1103,17 +1107,12 @@ static ssize_t compat_do_readv_writev(int type, struct file *file,
 	if (!file->f_op)
 		goto out;
 
-	ret = -EFAULT;
-	if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector)))
-		goto out;
-
-	tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs,
+	ret = compat_rw_copy_check_uvector(type, uvector, nr_segs,
 					       UIO_FASTIOV, iovstack, &iov, 1);
-	if (tot_len == 0) {
-		ret = 0;
+	if (ret <= 0)
 		goto out;
-	}
 
+	tot_len = ret;
 	ret = rw_verify_area(type, file, pos, tot_len);
 	if (ret < 0)
 		goto out;
@@ -1174,11 +1173,14 @@ compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
 	struct file *file;
 	int fput_needed;
 	ssize_t ret;
+	loff_t pos;
 
 	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
-	ret = compat_readv(file, vec, vlen, &file->f_pos);
+	pos = file->f_pos;
+	ret = compat_readv(file, vec, vlen, &pos);
+	file->f_pos = pos;
 	fput_light(file, fput_needed);
 	return ret;
 }
@@ -1233,11 +1235,14 @@ compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
 	struct file *file;
 	int fput_needed;
 	ssize_t ret;
+	loff_t pos;
 
 	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
-	ret = compat_writev(file, vec, vlen, &file->f_pos);
+	pos = file->f_pos;
+	ret = compat_writev(file, vec, vlen, &pos);
+	file->f_pos = pos;
 	fput_light(file, fput_needed);
 	return ret;
 }