Messages in this thread Patch in this message | | | From | Jordy Zomer <> | Subject | [PATCHv2] habanalabs: fix potential spectre v1 gadgets | Date | Wed, 2 Feb 2022 18:19:24 +0100 |
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It appears like nr could be a Spectre v1 gadget as it's supplied by a user and used as an array index. Prevent the contents of kernel memory from being leaked to userspace via speculative execution by using array_index_nospec.
Thanks for noticing Oded, made the changes.
Signed-off-by: Jordy Zomer <jordy@pwning.systems>
--- Changes v1 -> v2: Added the correct offsets --- drivers/misc/habanalabs/common/habanalabs_ioctl.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/misc/habanalabs/common/habanalabs_ioctl.c b/drivers/misc/habanalabs/common/habanalabs_ioctl.c index 3ba3a8ffda3e..c1cdf712a10d 100644 --- a/drivers/misc/habanalabs/common/habanalabs_ioctl.c +++ b/drivers/misc/habanalabs/common/habanalabs_ioctl.c @@ -14,6 +14,7 @@ #include <linux/fs.h> #include <linux/uaccess.h> #include <linux/slab.h> +#include <linux/nospec.h> static u32 hl_debug_struct_size[HL_DEBUG_OP_TIMESTAMP + 1] = { [HL_DEBUG_OP_ETR] = sizeof(struct hl_debug_params_etr), @@ -849,6 +850,7 @@ long hl_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) } if ((nr >= HL_COMMAND_START) && (nr < HL_COMMAND_END)) { + nr = array_index_nospec(nr, HL_COMMAND_END); ioctl = &hl_ioctls[nr]; } else { dev_err(hdev->dev, "invalid ioctl: pid=%d, nr=0x%02x\n", @@ -872,6 +874,7 @@ long hl_ioctl_control(struct file *filep, unsigned int cmd, unsigned long arg) } if (nr == _IOC_NR(HL_IOCTL_INFO)) { + nr = array_index_nospec(nr, _IOC_NR(HL_IOCTL_INFO)+1); ioctl = &hl_ioctls_control[nr]; } else { dev_err(hdev->dev_ctrl, "invalid ioctl: pid=%d, nr=0x%02x\n", -- 2.27.0
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