staging: erofs: fix to handle error path of erofs_vmap()

erofs_vmap() wrapped vmap() and vm_map_ram() to return virtual
continuous memory, but both of them can failed due to a lot of
reason, previously, erofs_vmap()'s callers didn't handle them,
which can potentially cause NULL pointer access, fix it.

Fixes: 3883a79abd ("staging: erofs: introduce VLE decompression support")
Fixes: 0d40d6e399 ("staging: erofs: add a generic z_erofs VLE decompressor")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Chao Yu 2019-03-11 23:10:10 +08:00 committed by Greg Kroah-Hartman
parent 4420a5611e
commit 8bce6dcede
2 changed files with 9 additions and 2 deletions

View file

@ -1029,6 +1029,10 @@ repeat:
skip_allocpage:
vout = erofs_vmap(pages, nr_pages);
if (!vout) {
err = -ENOMEM;
goto out;
}
err = z_erofs_vle_unzip_vmap(compressed_pages,
clusterpages, vout, llen, work->pageofs, overlapped);

View file

@ -136,10 +136,13 @@ int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages,
nr_pages = DIV_ROUND_UP(outlen + pageofs, PAGE_SIZE);
if (clusterpages == 1)
if (clusterpages == 1) {
vin = kmap_atomic(compressed_pages[0]);
else
} else {
vin = erofs_vmap(compressed_pages, clusterpages);
if (!vin)
return -ENOMEM;
}
preempt_disable();
vout = erofs_pcpubuf[smp_processor_id()].data;