[PATCH openEuler-5.10 1/4] swiotlb: fix info leak with DMA_FROM_DEVICE
From: Halil Pasic <pasic@linux.ibm.com> mainline inclusion from mainline-v5.17-rc6 commit ddbd89deb7d32b1fbb879f48d68fda1a8ac58e8e category: bugfix bugzilla: 186478, https://gitee.com/src-openeuler/kernel/issues/I503W4 CVE: CVE-2022-0854 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- The problem I'm addressing was discovered by the LTP test covering cve-2018-1000204. A short description of what happens follows: 1) The test case issues a command code 00 (TEST UNIT READY) via the SG_IO interface with: dxfer_len == 524288, dxdfer_dir == SG_DXFER_FROM_DEV and a corresponding dxferp. The peculiar thing about this is that TUR is not reading from the device. 2) In sg_start_req() the invocation of blk_rq_map_user() effectively bounces the user-space buffer. As if the device was to transfer into it. Since commit a45b599ad808 ("scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()") we make sure this first bounce buffer is allocated with GFP_ZERO. 3) For the rest of the story we keep ignoring that we have a TUR, so the device won't touch the buffer we prepare as if the we had a DMA_FROM_DEVICE type of situation. My setup uses a virtio-scsi device and the buffer allocated by SG is mapped by the function virtqueue_add_split() which uses DMA_FROM_DEVICE for the "in" sgs (here scatter-gather and not scsi generics). This mapping involves bouncing via the swiotlb (we need swiotlb to do virtio in protected guest like s390 Secure Execution, or AMD SEV). 4) When the SCSI TUR is done, we first copy back the content of the second (that is swiotlb) bounce buffer (which most likely contains some previous IO data), to the first bounce buffer, which contains all zeros. Then we copy back the content of the first bounce buffer to the user-space buffer. 5) The test case detects that the buffer, which it zero-initialized, ain't all zeros and fails. One can argue that this is an swiotlb problem, because without swiotlb we leak all zeros, and the swiotlb should be transparent in a sense that it does not affect the outcome (if all other participants are well behaved). Copying the content of the original buffer into the swiotlb buffer is the only way I can think of to make swiotlb transparent in such scenarios. So let's do just that if in doubt, but allow the driver to tell us that the whole mapped buffer is going to be overwritten, in which case we can preserve the old behavior and avoid the performance impact of the extra bounce. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Conflicts: kernel/dma/swiotlb.c Signed-off-by: Liu Shixin <liushixin2@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> --- Documentation/core-api/dma-attributes.rst | 8 ++++++++ include/linux/dma-mapping.h | 8 ++++++++ kernel/dma/swiotlb.c | 3 ++- 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/Documentation/core-api/dma-attributes.rst b/Documentation/core-api/dma-attributes.rst index 1887d92e8e92..17706dc91ec9 100644 --- a/Documentation/core-api/dma-attributes.rst +++ b/Documentation/core-api/dma-attributes.rst @@ -130,3 +130,11 @@ accesses to DMA buffers in both privileged "supervisor" and unprivileged subsystem that the buffer is fully accessible at the elevated privilege level (and ideally inaccessible or at least read-only at the lesser-privileged levels). + +DMA_ATTR_OVERWRITE +------------------ + +This is a hint to the DMA-mapping subsystem that the device is expected to +overwrite the entire mapped size, thus the caller does not require any of the +previous buffer contents to be preserved. This allows bounce-buffering +implementations to optimise DMA_FROM_DEVICE transfers. diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index a7d70cdee25e..a9361178c5db 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -61,6 +61,14 @@ */ #define DMA_ATTR_PRIVILEGED (1UL << 9) +/* + * This is a hint to the DMA-mapping subsystem that the device is expected + * to overwrite the entire mapped size, thus the caller does not require any + * of the previous buffer contents to be preserved. This allows + * bounce-buffering implementations to optimise DMA_FROM_DEVICE transfers. + */ +#define DMA_ATTR_OVERWRITE (1UL << 10) + /* * A dma_addr_t can hold any valid DMA or bus address for the platform. It can * be given to a device to use as a DMA source or target. It is specific to a diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 0ed0e1f215c7..62b1e5fa8673 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -598,7 +598,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, tlb_addr = slot_addr(io_tlb_start, index) + offset; if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) + (!(attrs & DMA_ATTR_OVERWRITE) || dir == DMA_TO_DEVICE || + dir == DMA_BIDIRECTIONAL)) swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); return tlb_addr; } -- 2.20.1
From: Linus Torvalds <torvalds@linux-foundation.org> mainline inclusion from mainline-v5.18-rc1 commit 901c7280ca0d5e2b4a8929fbe0bfb007ac2a6544 category: bugfix bugzilla: 186478, https://gitee.com/src-openeuler/kernel/issues/I503W4 CVE: CVE-2022-0854 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Halil Pasic points out [1] that the full revert of that commit (revert in bddac7c1e02b), and that a partial revert that only reverts the problematic case, but still keeps some of the cleanups is probably better.  And that partial revert [2] had already been verified by Oleksandr Natalenko to also fix the issue, I had just missed that in the long discussion. So let's reinstate the cleanups from commit aa6f8dcbab47 ("swiotlb: rework "fix info leak with DMA_FROM_DEVICE""), and effectively only revert the part that caused problems. Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1] Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2] Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3] Suggested-by: Halil Pasic <pasic@linux.ibm.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Cc: Christoph Hellwig" <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Conflicts: kernel/dma/swiotlb.c Signed-off-by: Liu Shixin <liushixin2@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> --- Documentation/core-api/dma-attributes.rst | 8 -------- include/linux/dma-mapping.h | 8 -------- kernel/dma/swiotlb.c | 12 ++++++++---- 3 files changed, 8 insertions(+), 20 deletions(-) diff --git a/Documentation/core-api/dma-attributes.rst b/Documentation/core-api/dma-attributes.rst index 17706dc91ec9..1887d92e8e92 100644 --- a/Documentation/core-api/dma-attributes.rst +++ b/Documentation/core-api/dma-attributes.rst @@ -130,11 +130,3 @@ accesses to DMA buffers in both privileged "supervisor" and unprivileged subsystem that the buffer is fully accessible at the elevated privilege level (and ideally inaccessible or at least read-only at the lesser-privileged levels). - -DMA_ATTR_OVERWRITE ------------------- - -This is a hint to the DMA-mapping subsystem that the device is expected to -overwrite the entire mapped size, thus the caller does not require any of the -previous buffer contents to be preserved. This allows bounce-buffering -implementations to optimise DMA_FROM_DEVICE transfers. diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index a9361178c5db..a7d70cdee25e 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -61,14 +61,6 @@ */ #define DMA_ATTR_PRIVILEGED (1UL << 9) -/* - * This is a hint to the DMA-mapping subsystem that the device is expected - * to overwrite the entire mapped size, thus the caller does not require any - * of the previous buffer contents to be preserved. This allows - * bounce-buffering implementations to optimise DMA_FROM_DEVICE transfers. - */ -#define DMA_ATTR_OVERWRITE (1UL << 10) - /* * A dma_addr_t can hold any valid DMA or bus address for the platform. It can * be given to a device to use as a DMA source or target. It is specific to a diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 62b1e5fa8673..274587a57717 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -597,10 +597,14 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, io_tlb_orig_addr[index + i] = slot_addr(orig_addr, i); tlb_addr = slot_addr(io_tlb_start, index) + offset; - if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - (!(attrs & DMA_ATTR_OVERWRITE) || dir == DMA_TO_DEVICE || - dir == DMA_BIDIRECTIONAL)) - swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); + /* + * When dir == DMA_FROM_DEVICE we could omit the copy from the orig + * to the tlb buffer, if we knew for sure the device will + * overwirte the entire current content. But we don't. Thus + * unconditional bounce may prevent leaking swiotlb content (i.e. + * kernel memory) to user-space. + */ + swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); return tlb_addr; } -- 2.20.1
From: Oliver Neukum <oneukum@suse.com> mainline inclusion from mainline-v5.17-rc4 commit e9da0b56fe27206b49f39805f7dcda8a89379062 category: bugfix bugzilla: 186472, https://gitee.com/src-openeuler/kernel/issues/I4ZQIZ CVE: CVE-2022-26966 -------------------------------- A malicious device can leak heap data to user space providing bogus frame lengths. Introduce a sanity check. Signed-off-by: Oliver Neukum <oneukum@suse.com> Reviewed-by: Grant Grundler <grundler@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Yue Haibing <yuehaibing@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> --- drivers/net/usb/sr9700.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index e04c8054c2cf..fce6713e970b 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -410,7 +410,7 @@ static int sr9700_rx_fixup(struct usbnet *dev, struct sk_buff *skb) /* ignore the CRC length */ len = (skb->data[1] | (skb->data[2] << 8)) - 4; - if (len > ETH_FRAME_LEN) + if (len > ETH_FRAME_LEN || len > skb->len) return 0; /* the last packet of current skb */ -- 2.20.1
From: Szymon Heidrich <szymon.heidrich@gmail.com> mainline inclusion from mainline-v5.17-rc4 commit 7f14c7227f342d9932f9b918893c8814f86d2a0d category: bugfix bugzilla: 186427, https://gitee.com/src-openeuler/kernel/issues/I4ZQJN CVE: CVE-2022-27223 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Assure that host may not manipulate the index to point past endpoint array. Signed-off-by: Szymon Heidrich <szymon.heidrich@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lijun Fang <fanglijun3@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> --- drivers/usb/gadget/udc/udc-xilinx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/gadget/udc/udc-xilinx.c b/drivers/usb/gadget/udc/udc-xilinx.c index d5e9d20c097d..096f56a09e6a 100644 --- a/drivers/usb/gadget/udc/udc-xilinx.c +++ b/drivers/usb/gadget/udc/udc-xilinx.c @@ -1612,6 +1612,8 @@ static void xudc_getstatus(struct xusb_udc *udc) break; case USB_RECIP_ENDPOINT: epnum = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK; + if (epnum >= XUSB_MAX_ENDPOINTS) + goto stall; target_ep = &udc->ep[epnum]; epcfgreg = udc->read_fn(udc->addr + target_ep->offset); halt = epcfgreg & XUSB_EP_CFG_STALL_MASK; @@ -1679,6 +1681,10 @@ static void xudc_set_clear_feature(struct xusb_udc *udc) case USB_RECIP_ENDPOINT: if (!udc->setup.wValue) { endpoint = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK; + if (endpoint >= XUSB_MAX_ENDPOINTS) { + xudc_ep0_stall(udc); + return; + } target_ep = &udc->ep[endpoint]; outinbit = udc->setup.wIndex & USB_ENDPOINT_DIR_MASK; outinbit = outinbit >> 7; -- 2.20.1
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Zheng Zengkai