Author: jhb Date: Thu Sep 6 20:29:40 2018 New Revision: 338511 URL: https://svnweb.freebsd.org/changeset/base/338511
Log: bhyve: Use MAP_GUARD when mapping guest memory ranges. Instead of relying on PROT_NONE mappings with MAP_ANON, use MAP_GUARD to reserve address space around guest memory ranges including the guard ranges of address space around mappings. Submitted by: Shawn Webb Reviewed by: araujo Approved by: re (rgrimes) MFC after: 1 month Sponsored by: HardendBSD and G2, Inc Differential Revision: https://reviews.freebsd.org/D16822 Modified: head/lib/libvmmapi/vmmapi.c Modified: head/lib/libvmmapi/vmmapi.c ============================================================================== --- head/lib/libvmmapi/vmmapi.c Thu Sep 6 20:02:19 2018 (r338510) +++ head/lib/libvmmapi/vmmapi.c Thu Sep 6 20:29:40 2018 (r338511) @@ -362,7 +362,7 @@ vm_setup_memory(struct vmctx *ctx, size_t memsize, enu size_t objsize, len; vm_paddr_t gpa; char *baseaddr, *ptr; - int error, flags; + int error; assert(vms == VM_MMAP_ALL); @@ -389,8 +389,7 @@ vm_setup_memory(struct vmctx *ctx, size_t memsize, enu * and the adjoining guard regions. */ len = VM_MMAP_GUARD_SIZE + objsize + VM_MMAP_GUARD_SIZE; - flags = MAP_PRIVATE | MAP_ANON | MAP_NOCORE | MAP_ALIGNED_SUPER; - ptr = mmap(NULL, len, PROT_NONE, flags, -1, 0); + ptr = mmap(NULL, len, PROT_NONE, MAP_GUARD | MAP_ALIGNED_SUPER, -1, 0); if (ptr == MAP_FAILED) return (-1); @@ -492,8 +491,8 @@ vm_create_devmem(struct vmctx *ctx, int segid, const c * adjoining guard regions. */ len2 = VM_MMAP_GUARD_SIZE + len + VM_MMAP_GUARD_SIZE; - flags = MAP_PRIVATE | MAP_ANON | MAP_NOCORE | MAP_ALIGNED_SUPER; - base = mmap(NULL, len2, PROT_NONE, flags, -1, 0); + base = mmap(NULL, len2, PROT_NONE, MAP_GUARD | MAP_ALIGNED_SUPER, -1, + 0); if (base == MAP_FAILED) goto done; _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
