جزئیات آسیب‌پذیری

In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: validate DRAW_PRIMITIVES header size before division vmw_cmd_draw() computes maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl); where header->size is u32 and is taken straight from the user-supplied command stream. When header->size is less than sizeof(cmd->body) the unsigned subtraction wraps to nearly 4 GiB, producing a huge maxnum. Any user-controlled cmd->body.numVertexDecls then passes the bound and the loop dereferences decl[i] far past the end of the kernel command bounce buffer, producing an out-of-bounds read of kernel memory. Reject undersized headers up front.

• https://git.kernel.org/stable/c/b89ca4bba820f79dde52af15ee139fe6e8bbc314
• https://git.kernel.org/stable/c/bef30317fcb4c838a37bceb2fc76256eb6b975c1
• https://git.kernel.org/stable/c/112c6ff29a56f3a22db4d5af869697aa07035ad6
• https://git.kernel.org/stable/c/2666cddf0dd218aa9bd1f99db688d1b532eac21a
• https://git.kernel.org/stable/c/fc0c02f510e41650df3479f96e257acf87d8a20a
• https://git.kernel.org/stable/c/dc0be7662b7b0ce28cb5eea864737793ed7b9e70
• https://git.kernel.org/stable/c/c77cf8edae2bd3a1599115301cc7c98d0c78e731
• https://git.kernel.org/stable/c/85891d174707d8bddcec7a888fb4e1d17def34f3