From: Chao Yu yuchao0@huawei.com

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: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Fixes: 0d40d6e399c1 ("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 --- drivers/staging/erofs/unzip_vle.c | 4 ++++ drivers/staging/erofs/unzip_vle_lz4.c | 7 +++++-- 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index 2b5951f233db..396f38b1c1b2 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -1010,6 +1010,10 @@ static int z_erofs_vle_unzip(struct super_block *sb,

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); diff --git a/drivers/staging/erofs/unzip_vle_lz4.c b/drivers/staging/erofs/unzip_vle_lz4.c index 8e8d705a6861..cff293710663 100644 --- a/drivers/staging/erofs/unzip_vle_lz4.c +++ b/drivers/staging/erofs/unzip_vle_lz4.c @@ -137,10 +137,13 @@ 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;