This is a note to let you know that I've just added the patch titled

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

to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From 8bce6dcede65139a087ff240127e3f3c01363eed Mon Sep 17 00:00:00 2001

From: Chao Yu yuchao0@huawei.com Date: Mon, 11 Mar 2019 23:10:10 +0800 Subject: 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: 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 8715bc50e09c..c7b3b21123c1 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -1029,6 +1029,10 @@ 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 48b263a2731a..0daac9b984a8 100644 --- a/drivers/staging/erofs/unzip_vle_lz4.c +++ b/drivers/staging/erofs/unzip_vle_lz4.c @@ -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;