diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/iov_iter.c | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c index c3ca28ca68a6..98e8425b060d 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -520,6 +520,8 @@ static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes, size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { + if (WARN_ON_ONCE(i->data_source)) + return 0; if (unlikely(iov_iter_is_pipe(i))) return copy_pipe_to_iter(addr, bytes, i); if (user_backed_iter(i)) @@ -606,6 +608,8 @@ static size_t copy_mc_pipe_to_iter(const void *addr, size_t bytes, */ size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { + if (WARN_ON_ONCE(i->data_source)) + return 0; if (unlikely(iov_iter_is_pipe(i))) return copy_mc_pipe_to_iter(addr, bytes, i); if (user_backed_iter(i)) @@ -622,10 +626,9 @@ EXPORT_SYMBOL_GPL(_copy_mc_to_iter); size_t _copy_from_iter(void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(iov_iter_is_pipe(i))) { - WARN_ON(1); + if (WARN_ON_ONCE(!i->data_source)) return 0; - } + if (user_backed_iter(i)) might_fault(); iterate_and_advance(i, bytes, base, len, off, @@ -639,10 +642,9 @@ EXPORT_SYMBOL(_copy_from_iter); size_t _copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(iov_iter_is_pipe(i))) { - WARN_ON(1); + if (WARN_ON_ONCE(!i->data_source)) return 0; - } + iterate_and_advance(i, bytes, base, len, off, __copy_from_user_inatomic_nocache(addr + off, base, len), memcpy(addr + off, base, len) @@ -671,10 +673,9 @@ EXPORT_SYMBOL(_copy_from_iter_nocache); */ size_t _copy_from_iter_flushcache(void *addr, size_t bytes, struct iov_iter *i) { - if (unlikely(iov_iter_is_pipe(i))) { - WARN_ON(1); + if (WARN_ON_ONCE(!i->data_source)) return 0; - } + iterate_and_advance(i, bytes, base, len, off, __copy_from_user_flushcache(addr + off, base, len), memcpy_flushcache(addr + off, base, len) @@ -703,17 +704,18 @@ static inline bool page_copy_sane(struct page *page, size_t offset, size_t n) head = compound_head(page); v += (page - head) << PAGE_SHIFT; - if (likely(n <= v && v <= (page_size(head)))) - return true; - WARN_ON(1); - return false; + if (WARN_ON(n > v || v > page_size(head))) + return false; + return true; } size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, struct iov_iter *i) { size_t res = 0; - if (unlikely(!page_copy_sane(page, offset, bytes))) + if (!page_copy_sane(page, offset, bytes)) + return 0; + if (WARN_ON_ONCE(i->data_source)) return 0; if (unlikely(iov_iter_is_pipe(i))) return copy_page_to_iter_pipe(page, offset, bytes, i); @@ -808,13 +810,12 @@ size_t copy_page_from_iter_atomic(struct page *page, unsigned offset, size_t byt struct iov_iter *i) { char *kaddr = kmap_atomic(page), *p = kaddr + offset; - if (unlikely(!page_copy_sane(page, offset, bytes))) { + if (!page_copy_sane(page, offset, bytes)) { kunmap_atomic(kaddr); return 0; } - if (unlikely(iov_iter_is_pipe(i) || iov_iter_is_discard(i))) { + if (WARN_ON_ONCE(!i->data_source)) { kunmap_atomic(kaddr); - WARN_ON(1); return 0; } iterate_and_advance(i, bytes, base, len, off, @@ -1526,10 +1527,9 @@ size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, { __wsum sum, next; sum = *csum; - if (unlikely(iov_iter_is_pipe(i) || iov_iter_is_discard(i))) { - WARN_ON(1); + if (WARN_ON_ONCE(!i->data_source)) return 0; - } + iterate_and_advance(i, bytes, base, len, off, ({ next = csum_and_copy_from_user(base, addr + off, len); sum = csum_block_add(sum, next, off); @@ -1549,9 +1549,15 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate, struct csum_state *csstate = _csstate; __wsum sum, next; - if (unlikely(iov_iter_is_discard(i))) { - WARN_ON(1); /* for now */ + if (WARN_ON_ONCE(i->data_source)) return 0; + if (unlikely(iov_iter_is_discard(i))) { + // can't use csum_memcpy() for that one - data is not copied + csstate->csum = csum_block_add(csstate->csum, + csum_partial(addr, bytes, 0), + csstate->off); + csstate->off += bytes; + return bytes; } sum = csum_shift(csstate->csum, csstate->off); |