From: Jan Glauber Subject: Re: [PATCH 1/2] crypto: thunderx_zip: Fix fallout from CONFIG_VMAP_STACK Date: Thu, 5 Apr 2018 10:40:18 +0200 Message-ID: <20180405084018.GB24281@hc> References: <20180328130557.10560-1-jglauber@cavium.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "David S . Miller" , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Mahipal Challa , Robert Richter , stable To: Herbert Xu Return-path: Content-Disposition: inline In-Reply-To: <20180328130557.10560-1-jglauber@cavium.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org On Wed, Mar 28, 2018 at 03:05:56PM +0200, Jan Glauber wrote: > Enabling virtual mapped kernel stacks breaks the thunderx_zip > driver. On compression or decompression the executing CPU hangs > in an endless loop. The reason for this is the usage of __pa > by the driver which does no longer work for an address that is > not part of the 1:1 mapping. > > The zip driver allocates a result struct on the stack and needs > to tell the hardware the physical address within this struct > that is used to signal the completion of the request. > > As the hardware gets the wrong address after the broken __pa > conversion it writes to an arbitrary address. The zip driver then > waits forever for the completion byte to contain a non-zero value. > > Allocating the result struct from 1:1 mapped memory resolves this > bug. Hi Herbert, Just realized that we might sleep in this path, so GFP_KERNEL wont work here. Same with usleep in the second patch. I'll respin the patches. --Jan > Signed-off-by: Jan Glauber > Reviewed-by: Robert Richter > Cc: stable # 4.14 > --- > drivers/crypto/cavium/zip/zip_crypto.c | 22 ++++++++++++++-------- > 1 file changed, 14 insertions(+), 8 deletions(-) > > diff --git a/drivers/crypto/cavium/zip/zip_crypto.c b/drivers/crypto/cavium/zip/zip_crypto.c > index 8df4d26..2fc9b03 100644 > --- a/drivers/crypto/cavium/zip/zip_crypto.c > +++ b/drivers/crypto/cavium/zip/zip_crypto.c > @@ -124,7 +124,7 @@ int zip_compress(const u8 *src, unsigned int slen, > struct zip_kernel_ctx *zip_ctx) > { > struct zip_operation *zip_ops = NULL; > - struct zip_state zip_state; > + struct zip_state *zip_state; > struct zip_device *zip = NULL; > int ret; > > @@ -135,20 +135,23 @@ int zip_compress(const u8 *src, unsigned int slen, > if (!zip) > return -ENODEV; > > - memset(&zip_state, 0, sizeof(struct zip_state)); > + zip_state = kzalloc(sizeof(*zip_state), GFP_KERNEL); > + if (!zip_state) > + return -ENOMEM; > + > zip_ops = &zip_ctx->zip_comp; > > zip_ops->input_len = slen; > zip_ops->output_len = *dlen; > memcpy(zip_ops->input, src, slen); > > - ret = zip_deflate(zip_ops, &zip_state, zip); > + ret = zip_deflate(zip_ops, zip_state, zip); > > if (!ret) { > *dlen = zip_ops->output_len; > memcpy(dst, zip_ops->output, *dlen); > } > - > + kfree(zip_state); > return ret; > } > > @@ -157,7 +160,7 @@ int zip_decompress(const u8 *src, unsigned int slen, > struct zip_kernel_ctx *zip_ctx) > { > struct zip_operation *zip_ops = NULL; > - struct zip_state zip_state; > + struct zip_state *zip_state; > struct zip_device *zip = NULL; > int ret; > > @@ -168,7 +171,10 @@ int zip_decompress(const u8 *src, unsigned int slen, > if (!zip) > return -ENODEV; > > - memset(&zip_state, 0, sizeof(struct zip_state)); > + zip_state = kzalloc(sizeof(*zip_state), GFP_KERNEL); > + if (!zip_state) > + return -ENOMEM; > + > zip_ops = &zip_ctx->zip_decomp; > memcpy(zip_ops->input, src, slen); > > @@ -179,13 +185,13 @@ int zip_decompress(const u8 *src, unsigned int slen, > zip_ops->input_len = slen; > zip_ops->output_len = *dlen; > > - ret = zip_inflate(zip_ops, &zip_state, zip); > + ret = zip_inflate(zip_ops, zip_state, zip); > > if (!ret) { > *dlen = zip_ops->output_len; > memcpy(dst, zip_ops->output, *dlen); > } > - > + kfree(zip_state); > return ret; > } > > -- > 2.7.4