In the recent work to remove page->index, a sanity check
that ensured all the readhead pages were covered by the
Squashfs data block was removed [1].
To avoid any regression, this commit adds the sanity check
back in an equivalent way. Namely the page actor will now
return error if any pages are unused after completion.
[1] https://lore.kernel.org/all/
20240818235847.170468-3-phillip@squashfs.org.uk/
--
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Link: https://lore.kernel.org/r/20240822233106.121522-1-phillip@squashfs.org.uk
V3: last_page should be actor->last_page
Signed-off-by: Christian Brauner <brauner@kernel.org>
last_page = squashfs_page_actor_free(actor);
- if (copied == expected) {
+ if (copied == expected && !IS_ERR(last_page)) {
/* Last page (if present) may have trailing bytes not filled */
bytes = copied % PAGE_SIZE;
if (bytes && last_page)
last_page = squashfs_page_actor_free(actor);
- if (res == expected) {
+ if (res == expected && !IS_ERR(last_page)) {
int bytes;
/* Last page (if present) may have trailing bytes not filled */
if (res < 0)
goto mark_errored;
- if (res != expected) {
+ if (res != expected || IS_ERR(last_page)) {
res = -EIO;
goto mark_errored;
}
loff_t start_index);
static inline struct page *squashfs_page_actor_free(struct squashfs_page_actor *actor)
{
- struct page *last_page = actor->last_page;
+ struct page *last_page = actor->next_page == actor->pages ? actor->last_page : ERR_PTR(-EIO);
kfree(actor->tmp_buffer);
kfree(actor);
+
return last_page;
}
static inline void *squashfs_first_page(struct squashfs_page_actor *actor)