aboutsummaryrefslogtreecommitdiffstats
path: root/tools/libxc/xc_hvm_build_x86.c
Commit message (Collapse)AuthorAgeFilesLines
* libxc: silence HVM domain creation messagesMatthew Daley2013-08-201-2/+2
| | | | | | | | | | | There's no need for xl to output these messages on HVM domain creation to stderr by default. Change their loglevels from XTL_INFO to XTL_DETAIL; then the messages output by xl are the same as those for PV domain creation. These now-silenced messages can still be seen using verbose (-v) mode. Signed-off-by: Matthew Daley <mattjd@gmail.com>
* libelf: Make all callers call elf_check_brokenIan Jackson2013-06-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This arranges that if the new pointer reference error checking tripped, we actually get a message about it. In this patch these messages do not change the actual return values from the various functions: so pointer reference errors do not prevent loading. This is for fear that some existing kernels might cause the code to make these wild references, which would then break, which is not a good thing in a security patch. In xen/arch/x86/domain_build.c we have to introduce an "out" label and change all of the "return rc" beyond the relevant point into "goto out". This is part of the fix to a security issue, XSA-55. Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com> Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> v5: Fix two whitespace errors. v3.1: Add error check to xc_dom_parse_elf_kernel. Move check in xc_hvm_build_x86.c:setup_guest to right place. v2 was Acked-by: Ian Campbell <ian.campbell@citrix.com> v2 was Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> v2: Style fixes.
* libelf: check all pointer accessesIan Jackson2013-06-141-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We change the ELF_PTRVAL and ELF_HANDLE types and associated macros: * PTRVAL becomes a uintptr_t, for which we provide a typedef elf_ptrval. This means no arithmetic done on it can overflow so the compiler cannot do any malicious invalid pointer arithmetic "optimisations". It also means that any places where we dereference one of these pointers without using the appropriate macros or functions become a compilation error. So we can be sure that we won't miss any memory accesses. All the PTRVAL variables were previously void* or char*, so the actual address calculations are unchanged. * ELF_HANDLE becomes a union, one half of which keeps the pointer value and the other half of which is just there to record the type. The new type is not a pointer type so there can be no address calculations on it whose meaning would change. Every assignment or access has to go through one of our macros. * The distinction between const and non-const pointers and char*s and void*s in libelf goes away. This was not important (and anyway libelf tended to cast away const in various places). * The fields elf->image and elf->dest are renamed. That proves that we haven't missed any unchecked uses of these actual pointer values. * The caller may fill in elf->caller_xdest_base and _size to specify another range of memory which is safe for libelf to access, besides the input and output images. * When accesses fail due to being out of range, we mark the elf "broken". This will be checked and used for diagnostics in a following patch. We do not check for write accesses to the input image. This is because libelf actually does this in a number of places. So we simply permit that. * Each caller of libelf which used to set dest now sets dest_base and dest_size. * In xc_dom_load_elf_symtab we provide a new actual-pointer value hdr_ptr which we get from mapping the guest's kernel area and use (checking carefully) as the caller_xdest area. * The STAR(h) macro in libelf-dominfo.c now uses elf_access_unsigned. * elf-init uses the new elf_uval_3264 accessor to access the 32-bit fields, rather than an unchecked field access (ie, unchecked pointer access). * elf_uval has been reworked to use elf_uval_3264. Both of these macros are essentially new in this patch (although they are derived from the old elf_uval) and need careful review. * ELF_ADVANCE_DEST is now safe in the sense that you can use it to chop parts off the front of the dest area but if you chop more than is available, the dest area is simply set to be empty, preventing future accesses. * We introduce some #defines for memcpy, memset, memmove and strcpy: - We provide elf_memcpy_safe and elf_memset_safe which take PTRVALs and do checking on the supplied pointers. - Users inside libelf must all be changed to either elf_mem*_unchecked (which are just like mem*), or elf_mem*_safe (which take PTRVALs) and are checked. Any unchanged call sites become compilation errors. * We do _not_ at this time fix elf_access_unsigned so that it doesn't make unaligned accesses. We hope that unaligned accesses are OK on every supported architecture. But it does check the supplied pointer for validity. This is part of the fix to a security issue, XSA-55. Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> v7: Remove a spurious whitespace change. v5: Use allow_size value from xc_dom_vaddr_to_ptr to set xdest_size correctly. If ELF_ADVANCE_DEST advances past the end, mark the elf broken. Always regard NULL allowable region pointers (e.g. dest_base) as invalid (since NULL pointers don't point anywhere). v4: Fix ELF_UNSAFE_PTR to work on 32-bit even when provided 64-bit values. Fix xc_dom_load_elf_symtab not to call XC_DOM_PAGE_SIZE unnecessarily if load is false. This was a regression. v3.1: Introduce a change to elf_store_field to undo the effects of the v3.1 change to the previous patch (the definition there is not compatible with the new types). v3: Fix a whitespace error. v2 was Acked-by: Ian Campbell <ian.campbell@citrix.com> v2: BUGFIX: elf_strval: Fix loop termination condition to actually work. BUGFIX: elf_strval: Fix return value to not always be totally wild. BUGFIX: xc_dom_load_elf_symtab: do proper check for small header size. xc_dom_load_elf_symtab: narrow scope of `hdr_ptr'. xc_dom_load_elf_symtab: split out uninit'd symtab.class ref fix. More comments on the lifetime/validity of elf-> dest ptrs etc. libelf.h: write "obsolete" out in full libelf.h: rename "dontuse" to "typeonly" and add doc comment elf_ptrval_in_range: Document trustedness of arguments. Style and commit message fixes.
* libelf: introduce macros for memory access and pointer handlingIan Jackson2013-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We introduce a collection of macros which abstract away all the pointer arithmetic and dereferences used for accessing the input ELF and the output area(s). We use the new macros everywhere. For now, these macros are semantically identical to the code they replace, so this patch has no functional change. elf_is_elfbinary is an exception: since it doesn't take an elf*, we need to handle it differently. In a future patch we will change it to take, and check, a length parameter. For now we just mark it with a fixme. That this patch has no functional change can be verified as follows: 0. Copy the scripts "comparison-generate" and "function-filter" out of this commit message. 1. Check out the tree before this patch. 2. Run the script ../comparison-generate .... ../before 3. Check out the tree after this patch. 4. Run the script ../comparison-generate .... ../after 5. diff --exclude=\*.[soi] -ruN before/ after/ |less Expect these differences: * stubdom/zlib-x86_64/ztest*.s2 The filename of this test file apparently contains the pid. * xen/common/version.s2 The xen build timestamp appears in two diff hunks. Verification that this is all that's needed: In a completely built xen.git, find * -name .*.d -type f | xargs grep -l libelf\.h Expect results in: xen/arch/x86: Checked above. tools/libxc: Checked above. tools/xcutils/readnotes: Checked above. tools/xenstore: Checked above. xen/common/libelf: This is the build for the hypervisor; checked in B above. stubdom: We have one stubdom which reads ELFs using our libelf, pvgrub, which is checked above. I have not done this verification for ARM. This is part of the fix to a security issue, XSA-55. Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> v7: Add uintptr_t cast to ELF_UNSAFE_PTR. Still verifies. Use git foo not git-foo in commit message verification script. v4: Fix elf_load_binary's phdr message to be correct on 32-bit. Fix ELF_OBSOLETE_VOIDP_CAST to work on 32-bit. Indent scripts in commit message. v3.1: Change elf_store_field to verify correctly on 32-bit. comparison-generate copes with Xen 4.1's lack of ./configure. v2: Use Xen style for multi-line comments. Postpone changes to readnotes.c:print_l1_mfn_valid_note. Much improved verification instructions with new script. Fixed commit message subject. -8<- comparison-generate -8<- #!/bin/bash # usage: # cd xen.git # .../comparison-generate OUR-CONFIG BUILD-RUNE-PREFIX ../before|../after # eg: # .../comparison-generate ~/work/.config 'schroot -pc64 --' ../before set -ex test $# = 3 || need-exactly-three-arguments our_config=$1 build_rune_prefix=$2 result_dir=$3 git clean -x -d -f cp "$our_config" . cat <<END >>.config debug_symbols=n CFLAGS += -save-temps END perl -i~ -pe 's/ -g / -g0 / if m/^CFLAGS/' xen/Rules.mk if [ -f ./configure ]; then $build_rune_prefix ./configure fi $build_rune_prefix make -C xen $build_rune_prefix make -C tools/include $build_rune_prefix make -C stubdom grub $build_rune_prefix make -C tools/libxc $build_rune_prefix make -C tools/xenstore $build_rune_prefix make -C tools/xcutils rm -rf "$result_dir" mkdir "$result_dir" set +x for f in `find xen tools stubdom -name \*.[soi]`; do mkdir -p "$result_dir"/`dirname $f` cp $f "$result_dir"/${f} case $f in *.s) ../function-filter <$f >"$result_dir"/${f}2 ;; esac done echo ok. -8<- -8<- function-filter -8<- #!/usr/bin/perl -w # function-filter # script for massaging gcc-generated labels to be consistent use strict; our @lines; my $sedderybody = "sub seddery () {\n"; while (<>) { push @lines, $_; if (m/^(__FUNCTION__|__func__)\.(\d+)\:/) { $sedderybody .= " s/\\b$1\\.$2\\b/__XSA55MANGLED__$1.$./g;\n"; } } $sedderybody .= "}\n1;\n"; eval $sedderybody or die $@; foreach (@lines) { seddery(); print or die $!; } -8<-
* xc: use XENMEM_claim_pages hypercall during guest creation.Dan Magenheimer2013-04-161-4/+19
| | | | | | | | | | | | | | | | | | | | | | We add an extra parameter to the structures passed to the PV routine (arch_setup_meminit) and HVM routine (setup_guest) that determines whether the claim hypercall is to be done. The contents of the 'claim_enabled' is defined as an 'int' in case the hypercall expands in the future with extra flags (for example for per-NUMA allocation). For right now the proper values are: 0 to disable it or 1 to enable it. If the hypervisor does not support this function, the xc_domain_claim_pages and xc_domain_get_outstanding_pages will silently return 0 (and set errno to zero). Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com> [v2: Updated per Ian's recommendations] [v3: Added support for out-of-sync hypervisor] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
* Fix emacs local variable block to use correct C style variable.David Vrabel2013-02-211-1/+1
| | | | | | | The emacs variable to set the C style from a local variable block is c-file-style, not c-set-style. Signed-off-by: David Vrabel <david.vrabel@citrix.com
* HVM firmware passthrough control tools supportRoss Philipson2013-01-101-5/+120
| | | | | | | | | | | | Xen control tools support for loading the firmware passthrough blocks during domain construction. SMBIOS and ACPI blocks are passed in using the new xc_hvm_build_args structure. Each block is read and loaded into the new domain address space behind the HVMLOADER image. The base address for the two blocks is returned as an out parameter to the caller via the args structure. Signed-off-by: Ross Philipson <ross.philipson@citrix.com> Committed-by: Keir Fraser <keir@xen.org>
* x86/PoD: prevent guest from being destroyed upon early access to its memoryJan Beulich2012-08-161-14/+21
| | | | | | | | | | | | | | | | | | | | When an external agent (e.g. a monitoring daemon) happens to access the memory of a PoD guest prior to setting the PoD target, that access must fail for there not being any page in the PoD cache, and only the space above the low 2Mb gets scanned for victim pages (while only the low 2Mb got real pages populated so far). To accomodate for this - set the PoD target first - do all physmap population in PoD mode (i.e. not just large [2Mb or 1Gb] pages) - slightly lift the restrictions enforced by p2m_pod_set_mem_target() to accomodate for the changed tools behavior Tested-by: Jürgen Groß <juergen.gross@ts.fujitsu.com> (in a 4.0.x based incarnation) Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
* arm: compile libxenguestStefano Stabellini2012-05-301-0/+472
Introduce an empty implementation of the arch specific ARM functions in xc_dom_arm.c. Provide empty implementations of xc_domain_save and xc_domain_restore when CONFIG_MIGRATE is not set. Move xc_hvm_build.c to xc_hvm_build_x86.c because the implementation is x86 specific, introduce xc_hvm_build_arm.c with empty stubs. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com> Acked-by: Ian Campbell <Ian.Campbell@citrix.com> Committed-by: Ian Campbell <ian.campbell@citrix.com>