bcachefs: do_encrypt() now handles allocation failures

convert to darray, and add a fallback when allocation fails

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2024-09-01 15:24:11 -04:00
parent 3340dee235
commit b7d8092a1b

View File

@ -100,13 +100,12 @@ static inline int do_encrypt_sg(struct crypto_sync_skcipher *tfm,
struct scatterlist *sg, size_t len)
{
SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm);
int ret;
skcipher_request_set_sync_tfm(req, tfm);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, sg, sg, len, nonce.d);
ret = crypto_skcipher_encrypt(req);
int ret = crypto_skcipher_encrypt(req);
if (ret)
pr_err("got error %i from crypto_skcipher_encrypt()", ret);
@ -128,28 +127,41 @@ static inline int do_encrypt(struct crypto_sync_skcipher *tfm,
len, offset_in_page(buf));
return do_encrypt_sg(tfm, nonce, &sg, len);
} else {
unsigned pages = buf_pages(buf, len);
struct scatterlist *sg;
size_t orig_len = len;
int ret, i;
DARRAY_PREALLOCATED(struct scatterlist, 4) sgl;
size_t sgl_len = 0;
int ret;
sg = kmalloc_array(pages, sizeof(*sg), GFP_KERNEL);
if (!sg)
return -BCH_ERR_ENOMEM_do_encrypt;
darray_init(&sgl);
sg_init_table(sg, pages);
for (i = 0; i < pages; i++) {
while (len) {
unsigned offset = offset_in_page(buf);
unsigned pg_len = min_t(size_t, len, PAGE_SIZE - offset);
struct scatterlist sg = {
.page_link = (unsigned long) vmalloc_to_page(buf),
.offset = offset,
.length = min(len, PAGE_SIZE - offset),
};
sg_set_page(sg + i, vmalloc_to_page(buf), pg_len, offset);
buf += pg_len;
len -= pg_len;
if (darray_push(&sgl, sg)) {
sg_mark_end(&darray_last(sgl));
ret = do_encrypt_sg(tfm, nonce, sgl.data, sgl_len);
if (ret)
goto err;
nonce = nonce_add(nonce, sgl_len);
sgl_len = 0;
sgl.nr = 0;
BUG_ON(darray_push(&sgl, sg));
}
buf += sg.length;
len -= sg.length;
sgl_len += sg.length;
}
ret = do_encrypt_sg(tfm, nonce, sg, orig_len);
kfree(sg);
sg_mark_end(&darray_last(sgl));
ret = do_encrypt_sg(tfm, nonce, sgl.data, sgl_len);
err:
darray_exit(&sgl);
return ret;
}
}