4.18-stable review patch. If anyone has any objections, please let me know.
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From: Mikulas Patocka mpatocka@redhat.com
commit a788848116454d753b13a4888e0e31ada3c4d393 upstream.
This patch fixes gcmaes_crypt_by_sg so that it won't use memory allocation if the data doesn't cross a page boundary.
Authenticated encryption may be used by dm-crypt. If the encryption or decryption fails, it would result in I/O error and filesystem corruption. The function gcmaes_crypt_by_sg is using GFP_ATOMIC allocation that can fail anytime. This patch fixes the logic so that it won't attempt the failing allocation if the data doesn't cross a page boundary.
Signed-off-by: Mikulas Patocka mpatocka@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/crypto/aesni-intel_glue.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/crypto/aesni-intel_glue.c +++ b/arch/x86/crypto/aesni-intel_glue.c @@ -817,7 +817,7 @@ static int gcmaes_crypt_by_sg(bool enc, /* Linearize assoc, if not already linear */ if (req->src->length >= assoclen && req->src->length && (!PageHighMem(sg_page(req->src)) || - req->src->offset + req->src->length < PAGE_SIZE)) { + req->src->offset + req->src->length <= PAGE_SIZE)) { scatterwalk_start(&assoc_sg_walk, req->src); assoc = scatterwalk_map(&assoc_sg_walk); } else {