Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull iov_iter cleanups from Al Viro.
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fold checks into iterate_and_advance()
rw_verify_area(): saner calling conventions
aio: remove a pointless assignment
diff --git a/fs/aio.c b/fs/aio.c
index 155f842..a6deaa7 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1447,8 +1447,6 @@
return ret;
}
- len = ret;
-
if (rw == WRITE)
file_start_write(file);
diff --git a/fs/read_write.c b/fs/read_write.c
index 56425cd..933b53a 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -398,11 +398,6 @@
}
EXPORT_SYMBOL(vfs_iter_write);
-/*
- * rw_verify_area doesn't like huge counts. We limit
- * them to something that fits in "int" so that others
- * won't have to do range checks all the time.
- */
int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t count)
{
struct inode *inode;
@@ -429,11 +424,8 @@
if (retval < 0)
return retval;
}
- retval = security_file_permission(file,
+ return security_file_permission(file,
read_write == READ ? MAY_READ : MAY_WRITE);
- if (retval)
- return retval;
- return count > MAX_RW_COUNT ? MAX_RW_COUNT : count;
}
static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
@@ -477,8 +469,9 @@
return -EFAULT;
ret = rw_verify_area(READ, file, pos, count);
- if (ret >= 0) {
- count = ret;
+ if (!ret) {
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
ret = __vfs_read(file, buf, count, pos);
if (ret > 0) {
fsnotify_access(file);
@@ -560,8 +553,9 @@
return -EFAULT;
ret = rw_verify_area(WRITE, file, pos, count);
- if (ret >= 0) {
- count = ret;
+ if (!ret) {
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
file_start_write(file);
ret = __vfs_write(file, buf, count, pos);
if (ret > 0) {
@@ -1315,7 +1309,8 @@
retval = rw_verify_area(READ, in.file, &pos, count);
if (retval < 0)
goto fput_in;
- count = retval;
+ if (count > MAX_RW_COUNT)
+ count = MAX_RW_COUNT;
/*
* Get output file, and verify that it is ok..
@@ -1333,7 +1328,6 @@
retval = rw_verify_area(WRITE, out.file, &out_pos, count);
if (retval < 0)
goto fput_out;
- count = retval;
if (!max)
max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
@@ -1477,11 +1471,12 @@
if (flags != 0)
return -EINVAL;
- /* copy_file_range allows full ssize_t len, ignoring MAX_RW_COUNT */
ret = rw_verify_area(READ, file_in, &pos_in, len);
- if (ret >= 0)
- ret = rw_verify_area(WRITE, file_out, &pos_out, len);
- if (ret < 0)
+ if (unlikely(ret))
+ return ret;
+
+ ret = rw_verify_area(WRITE, file_out, &pos_out, len);
+ if (unlikely(ret))
return ret;
if (!(file_in->f_mode & FMODE_READ) ||
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index ca5316e..28cb431 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -99,40 +99,44 @@
}
#define iterate_and_advance(i, n, v, I, B, K) { \
- size_t skip = i->iov_offset; \
- if (unlikely(i->type & ITER_BVEC)) { \
- const struct bio_vec *bvec; \
- struct bio_vec v; \
- iterate_bvec(i, n, v, bvec, skip, (B)) \
- if (skip == bvec->bv_len) { \
- bvec++; \
- skip = 0; \
+ if (unlikely(i->count < n)) \
+ n = i->count; \
+ if (n) { \
+ size_t skip = i->iov_offset; \
+ if (unlikely(i->type & ITER_BVEC)) { \
+ const struct bio_vec *bvec; \
+ struct bio_vec v; \
+ iterate_bvec(i, n, v, bvec, skip, (B)) \
+ if (skip == bvec->bv_len) { \
+ bvec++; \
+ skip = 0; \
+ } \
+ i->nr_segs -= bvec - i->bvec; \
+ i->bvec = bvec; \
+ } else if (unlikely(i->type & ITER_KVEC)) { \
+ const struct kvec *kvec; \
+ struct kvec v; \
+ iterate_kvec(i, n, v, kvec, skip, (K)) \
+ if (skip == kvec->iov_len) { \
+ kvec++; \
+ skip = 0; \
+ } \
+ i->nr_segs -= kvec - i->kvec; \
+ i->kvec = kvec; \
+ } else { \
+ const struct iovec *iov; \
+ struct iovec v; \
+ iterate_iovec(i, n, v, iov, skip, (I)) \
+ if (skip == iov->iov_len) { \
+ iov++; \
+ skip = 0; \
+ } \
+ i->nr_segs -= iov - i->iov; \
+ i->iov = iov; \
} \
- i->nr_segs -= bvec - i->bvec; \
- i->bvec = bvec; \
- } else if (unlikely(i->type & ITER_KVEC)) { \
- const struct kvec *kvec; \
- struct kvec v; \
- iterate_kvec(i, n, v, kvec, skip, (K)) \
- if (skip == kvec->iov_len) { \
- kvec++; \
- skip = 0; \
- } \
- i->nr_segs -= kvec - i->kvec; \
- i->kvec = kvec; \
- } else { \
- const struct iovec *iov; \
- struct iovec v; \
- iterate_iovec(i, n, v, iov, skip, (I)) \
- if (skip == iov->iov_len) { \
- iov++; \
- skip = 0; \
- } \
- i->nr_segs -= iov - i->iov; \
- i->iov = iov; \
+ i->count -= n; \
+ i->iov_offset = skip; \
} \
- i->count -= n; \
- i->iov_offset = skip; \
}
static size_t copy_page_to_iter_iovec(struct page *page, size_t offset, size_t bytes,
@@ -386,12 +390,6 @@
size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
{
const char *from = addr;
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
iterate_and_advance(i, bytes, v,
__copy_to_user(v.iov_base, (from += v.iov_len) - v.iov_len,
v.iov_len),
@@ -407,12 +405,6 @@
size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
{
char *to = addr;
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
iterate_and_advance(i, bytes, v,
__copy_from_user((to += v.iov_len) - v.iov_len, v.iov_base,
v.iov_len),
@@ -428,12 +420,6 @@
size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
{
char *to = addr;
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
iterate_and_advance(i, bytes, v,
__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len),
@@ -474,12 +460,6 @@
size_t iov_iter_zero(size_t bytes, struct iov_iter *i)
{
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
iterate_and_advance(i, bytes, v,
__clear_user(v.iov_base, v.iov_len),
memzero_page(v.bv_page, v.bv_offset, v.bv_len),
@@ -685,12 +665,6 @@
char *to = addr;
__wsum sum, next;
size_t off = 0;
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
sum = *csum;
iterate_and_advance(i, bytes, v, ({
int err = 0;
@@ -729,12 +703,6 @@
const char *from = addr;
__wsum sum, next;
size_t off = 0;
- if (unlikely(bytes > i->count))
- bytes = i->count;
-
- if (unlikely(!bytes))
- return 0;
-
sum = *csum;
iterate_and_advance(i, bytes, v, ({
int err = 0;