Merge tag 'docs-5.0-fix' of git://git.lwn.net/linux

[sfrench/cifs-2.6.git] / lib / iov_iter.c

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 1928009f506e8e4531cea681257da6df4b8a8024..be4bd627caf060cd89aa41ac88208946da568035 100644 (file)
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -136,7 +136,7 @@
 
 static int copyout(void __user *to, const void *from, size_t n)
 {
-       if (access_ok(VERIFY_WRITE, to, n)) {
+       if (access_ok(to, n)) {
                kasan_check_read(from, n);
                n = raw_copy_to_user(to, from, n);
        }
@@ -145,7 +145,7 @@ static int copyout(void __user *to, const void *from, size_t n)
 
 static int copyin(void *to, const void __user *from, size_t n)
 {
-       if (access_ok(VERIFY_READ, from, n)) {
+       if (access_ok(from, n)) {
                kasan_check_write(to, n);
                n = raw_copy_from_user(to, from, n);
        }
@@ -561,13 +561,20 @@ static size_t copy_pipe_to_iter(const void *addr, size_t bytes,
        return bytes;
 }
 
+static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
+                             __wsum sum, size_t off)
+{
+       __wsum next = csum_partial_copy_nocheck(from, to, len, 0);
+       return csum_block_add(sum, next, off);
+}
+
 static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes,
                                __wsum *csum, struct iov_iter *i)
 {
        struct pipe_inode_info *pipe = i->pipe;
        size_t n, r;
        size_t off = 0;
-       __wsum sum = *csum, next;
+       __wsum sum = *csum;
        int idx;
 
        if (!sanity(i))
@@ -579,8 +586,7 @@ static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes,
        for ( ; n; idx = next_idx(idx, pipe), r = 0) {
                size_t chunk = min_t(size_t, n, PAGE_SIZE - r);
                char *p = kmap_atomic(pipe->bufs[idx].page);
-               next = csum_partial_copy_nocheck(addr, p + r, chunk, 0);
-               sum = csum_block_add(sum, next, off);
+               sum = csum_and_memcpy(p + r, addr, chunk, sum, off);
                kunmap_atomic(p);
                i->idx = idx;
                i->iov_offset = r + chunk;
@@ -614,7 +620,7 @@ EXPORT_SYMBOL(_copy_to_iter);
 #ifdef CONFIG_ARCH_HAS_UACCESS_MCSAFE
 static int copyout_mcsafe(void __user *to, const void *from, size_t n)
 {
-       if (access_ok(VERIFY_WRITE, to, n)) {
+       if (access_ok(to, n)) {
                kasan_check_read(from, n);
                n = copy_to_user_mcsafe((__force void *) to, from, n);
        }
@@ -1401,17 +1407,15 @@ size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
                err ? v.iov_len : 0;
        }), ({
                char *p = kmap_atomic(v.bv_page);
-               next = csum_partial_copy_nocheck(p + v.bv_offset,
-                                                (to += v.bv_len) - v.bv_len,
-                                                v.bv_len, 0);
+               sum = csum_and_memcpy((to += v.bv_len) - v.bv_len,
+                                     p + v.bv_offset, v.bv_len,
+                                     sum, off);
                kunmap_atomic(p);
-               sum = csum_block_add(sum, next, off);
                off += v.bv_len;
        }),({
-               next = csum_partial_copy_nocheck(v.iov_base,
-                                                (to += v.iov_len) - v.iov_len,
-                                                v.iov_len, 0);
-               sum = csum_block_add(sum, next, off);
+               sum = csum_and_memcpy((to += v.iov_len) - v.iov_len,
+                                     v.iov_base, v.iov_len,
+                                     sum, off);
                off += v.iov_len;
        })
        )
@@ -1445,17 +1449,15 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum,
                0;
        }), ({
                char *p = kmap_atomic(v.bv_page);
-               next = csum_partial_copy_nocheck(p + v.bv_offset,
-                                                (to += v.bv_len) - v.bv_len,
-                                                v.bv_len, 0);
+               sum = csum_and_memcpy((to += v.bv_len) - v.bv_len,
+                                     p + v.bv_offset, v.bv_len,
+                                     sum, off);
                kunmap_atomic(p);
-               sum = csum_block_add(sum, next, off);
                off += v.bv_len;
        }),({
-               next = csum_partial_copy_nocheck(v.iov_base,
-                                                (to += v.iov_len) - v.iov_len,
-                                                v.iov_len, 0);
-               sum = csum_block_add(sum, next, off);
+               sum = csum_and_memcpy((to += v.iov_len) - v.iov_len,
+                                     v.iov_base, v.iov_len,
+                                     sum, off);
                off += v.iov_len;
        })
        )
@@ -1493,17 +1495,15 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump,
                err ? v.iov_len : 0;
        }), ({
                char *p = kmap_atomic(v.bv_page);
-               next = csum_partial_copy_nocheck((from += v.bv_len) - v.bv_len,
-                                                p + v.bv_offset,
-                                                v.bv_len, 0);
+               sum = csum_and_memcpy(p + v.bv_offset,
+                                     (from += v.bv_len) - v.bv_len,
+                                     v.bv_len, sum, off);
                kunmap_atomic(p);
-               sum = csum_block_add(sum, next, off);
                off += v.bv_len;
        }),({
-               next = csum_partial_copy_nocheck((from += v.iov_len) - v.iov_len,
-                                                v.iov_base,
-                                                v.iov_len, 0);
-               sum = csum_block_add(sum, next, off);
+               sum = csum_and_memcpy(v.iov_base,
+                                    (from += v.iov_len) - v.iov_len,
+                                    v.iov_len, sum, off);
                off += v.iov_len;
        })
        )
@@ -1663,7 +1663,7 @@ int import_single_range(int rw, void __user *buf, size_t len,
 {
        if (len > MAX_RW_COUNT)
                len = MAX_RW_COUNT;
-       if (unlikely(!access_ok(!rw, buf, len)))
+       if (unlikely(!access_ok(buf, len)))
                return -EFAULT;
 
        iov->iov_base = buf;