Commit Graph
37 Commits
Author SHA1 Message Date
Simon Gaiser 37f1a96888 libxc: xc_dom_parse_elf_kernel: Return error for invalid kernel images
Commit 96edb111dd ("libxc: panic when trying to create a PVH guest
without kernel support") already improved the handling of non PVH
capable kernels. But xc_dom_parse_elf_kernel() still returned success on
invalid elf images and the domain build only failed later. Now the build
process will fail immediately on detecting the error.

Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-02-13 11:48:43 +00:00
Simon Gaiser fc9061883a libxc: Cleanup xc_dom_parse_elf_kernel()'s return value
xc_dom_loader.parser() should return elf_negerrnoval.

Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-02-13 11:48:28 +00:00
Roger Pau Monne 96edb111dd libxc: panic when trying to create a PVH guest without kernel support
Previously when trying to boot a PV capable but not PVH capable kernel
inside of a PVH container xc_dom_guest_type would succeed and return a
PV guest type, which would lead to failures later on in the build
process.

Instead provide a clear error message when trying to create a PVH
guest using a kernel that doesn't support PVH.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2017-10-09 15:43:35 +01:00
Roger Pau Monne ed04ca9598 libelf: rewrite symtab/strtab loading
Current implementation of elf_load_bsdsyms is broken when loading inside of
a HVM guest, because it assumes elf_memcpy_safe is able to write into guest
memory space, which it is not.

Take the oportunity to do some cleanup and properly document how
elf_{parse/load}_bsdsyms works. The new implementation uses elf_load_image
when dealing with data that needs to be copied to the guest memory space.
Also reduce the number of section headers copied to the minimum necessary.

This patch also removes the duplication of code found in the libxc ELF
loader, since the libelf symtab/strtab loading code will also handle this
case without having to duplicate it.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2016-04-01 15:02:52 +01:00
Roger Pau Monné c2ba8c24f3 elfnotes: check phys_entry against UNSET_ADDR32
And introduce UNSET_ADDR32.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-01-19 16:06:31 +01:00
Roger Pau Monne 904fc1d7c9 libxc: switch xc_dom_elfloader to be used with HVMlite domains
Allow xc_dom_elfloader to report a guest type as hvm-3.0-x86_32 if it's
running inside of a HVM container and has the PHYS32_ENTRY elfnote set.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
2015-12-15 13:25:44 +00:00
Roger Pau Monne ad787bafcd libxc: introduce a domain loader for HVM guest firmware
Introduce a very simple (and dummy) domain loader to be used to load the
firmware (hvmloader) into HVM guests. Since hmvloader is just a 32bit elf
executable the loader is fairly simple.

Since the order in which loaders are tested cannot be arranged, prevent the
current elfloader from trying to boot a kernel that doesn't contain Xen
ELFNOTES.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2015-10-08 12:22:33 +01:00
Juergen Gross 5d3bcd64d9 cleanup domain builder declarations and related users
There are several unused function and structure declarations in the
hypervisor related to domain building. Remove them.

Use an enum for elf_dom_parms.pae instead of just hard coding the
values when setting the information and adjust the code to use those
instead of own macros (hypervisor and tools).

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2015-09-28 17:28:35 +02:00
Ian Campbell 443701ef0c Replace FSF street address with canonical URL
As recommended in http://www.gnu.org/licenses/gpl-howto.en.html.

This is the result of:
$ git grep -El Mass\|Temple\|Franklin | xargs ./fsf.pl

Where fsf.pl is:
    #!/usr/bin/perl -w -pi.bak -0777
    my $repl = 'If not, see <http://www.gnu.org/licenses/>.';
    my $br = qr/(?:\s*\n\s*(?:[\*\#]|\/\/|\.\\" )?\s*|\s+)/;

    my $inwt = qr/[Ii]f${br}not,${br}write${br}(?:to${br})?the${br}Free${br}Software${br}Foundation,(?:${br}Inc\.,)?/;

    my $mass = qr/675${br}Mass${br}Ave,?${br}Cambridge,?${br}MA${br}02139,?${br}USA,?\.?/;
    my $franklin = qr/51${br}Franklin${br}St(?:reet)?(?:,${br}| - )Fifth${br}Floor,?${br}Boston,?${br}MA,?${br}02110-1301,?${br}USA,?\.?/;
    my $temple = qr/59${br}Temple${br}Place(?:,${br}| - )Suite${br}330,?${br}Boston,?${br}MA,?${br}021110?-1307,?${br}USA,?\.?/;

    s|$inwt$br$mass|$repl|m;
    s|$inwt$br$franklin|$repl|m;
    s|$inwt$br$temple|$repl|m;

The only remaining mentions of these addresses are in COPYING files which I
haven't touched.

Some of the changed files are imports from elsewhere, however
filtering them out is tricky, I think it is tolerable to have these
files be modified here and then perhaps reverted on the next sync,
since it's only 1-2 lines and obvious what is going on.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
2015-07-29 11:14:07 +01:00
Roger Pau Monne 06ee606aaf libxc: fix xc_dom_load_elf_symtab
xc_dom_load_elf_symtab was incorrectly trying to perform the same
calculations already done in elf_parse_bsdsyms when load == 0 is used.
Instead of trying to repeat the calculations, just trust what
elf_parse_bsdsyms has already accounted for.

This also simplifies the code by allowing the non-load case to return
earlier.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2015-06-17 11:57:39 +01:00
Ian Jackson 3d5a1d4733 libxc: check return values from malloc
A sufficiently malformed input to libxc (such as a malformed input ELF
or other guest-controlled data) might cause one of libxc's malloc() to
fail.  In this case we need to make sure we don't dereference or do
pointer arithmetic on the result.

Search for all occurrences of \b(m|c|re)alloc in libxc, and all
functions which call them, and add appropriate error checking where
missing.

This includes the functions xc_dom_malloc*, which now print a message
when they fail so that callers don't have to do so.

The function xc_cpuid_to_str wasn't provided with a sane return value
and has a pretty strange API, which now becomes a little stranger.
There are no in-tree callers.

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>

v8: Move a check in xc_exchange_page to the previous patch
     (ie, remove it from this patch).

v7: Add a missing check for a call to alloc_str.
    Add arithmetic overflow check in xc_dom_malloc.
    Coding style fix.

v6: Fix a missed call `pfn_err = calloc...' in xc_domain_restore.c.
    Fix a missed call `new_pfn = xc_map_foreign_range...' in
     xc_offline_page.c

v5: This patch is new in this version of the series.
2013-06-14 16:39:38 +01:00
Ian Jackson aaebaba5ae libxc: check failure of xc_dom_*_to_ptr, xc_map_foreign_range
The return values from xc_dom_*_to_ptr and xc_map_foreign_range are
sometimes dereferenced, or subjected to pointer arithmetic, without
checking whether the relevant function failed and returned NULL.

Add an appropriate error check at every call site.

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>

v8: Add a missing check in xc_offline_page.c:xc_exchange_page,
     which was in the next patch in v7 of the series.
     Also improve the message.
     I think in this particular error case it may be that the results
     are a broken guest, but turning this from a possible host tools
     crash into a guest problem seems to solve the potential security
     problem.

v7: Simplify an error DOMPRINTF to not use "load ? : ".
    Make DOMPRINTF allocation error messages consistent.
    Do not set elf->dest_pages in xc_dom_load_elf_kernel
     if xc_dom_seg_to_ptr_pages fails.

v5: This patch is new in this version of the series.
2013-06-14 16:39:38 +01:00
Ian Jackson 66fe2726fe libelf: abolish obsolete macros
Abolish ELF_PTRVAL_[CONST_]{CHAR,VOID}; change uses to elf_ptrval.
Abolish ELF_HANDLE_DECL_NONCONST; change uses to ELF_HANDLE_DECL.
Abolish ELF_OBSOLETE_VOIDP_CAST; simply remove all uses.

No functional change.  (Verified by diffing assembler output.)

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: Andrew Cooper <andrew.cooper3@citrix.com>

v2: New patch.
2013-06-14 16:39:36 +01:00
Ian Jackson 39bf7b9d0a libelf: check loops for running away
Ensure that libelf does not have any loops which can run away
indefinitely even if the input is bogus.  (Grepped for \bfor, \bwhile
and \bgoto in libelf and xc_dom_*loader*.c.)

Changes needed:
 * elf_note_next uses the note's unchecked alleged length, which might
   wrap round.  If it does, return ELF_MAX_PTRVAL (0xfff..fff) instead,
   which will be beyond the end of the section and so terminate the
   caller's loop.  Also check that the returned psuedopointer is sane.
 * In various loops over section and program headers, check that the
   calculated header pointer is still within the image, and quit the
   loop if it isn't.
 * Some fixed limits to avoid potentially O(image_size^2) loops:
    - maximum length of strings: 4K (longer ones ignored totally)
    - maximum total number of ELF notes: 65536 (any more are ignored)
 * Check that the total program contents (text, data) we copy or
   initialise doesn't exceed twice the output image area size.
 * Remove an entirely useless loop from elf_xen_parse (!)
 * Replace a nested search loop in in xc_dom_load_elf_symtab in
   xc_dom_elfloader.c by a precomputation of a bitmap of referenced
   symtabs.

We have not changed loops which might, in principle, iterate over the
whole image - even if they might do so one byte at a time with a
nontrivial access check function in the middle.

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>

v8: Fix the two loops in libelf-dominfo.c; the comment about
     PT_NOTE and SHT_NOTE wasn't true because the checks did
     "continue", not "break".
    Add a comment about elf_note_next's expectations of the caller's
     loop conditions (which most plausible callers will follow anyway).

v5: Fix regression due to wrong image size loop limit calculation.
    Check return value from xc_dom_malloc.

v4: Fix regression due to misplacement of test in elf_shdr_by_name
     (uninitialised variable).
    Introduce fixed limits.
    Avoid O(size^2) loops.
    Check returned psuedopointer from elf_note_next is correct.
    A few style fixes.

v3: Fix a whitespace error.

v2: BUGFIX: elf_shdr_by_name, elf_note_next: Reject new <= old, not just <.
    elf_shdr_by_name: Change order of checks to be a bit clearer.
    elf_load_bsdsyms: shdr loop check, improve chance of brokenness detection.
    Style fixes.
2013-06-14 16:39:36 +01:00
Ian Jackson a004800f8f libelf: use only unsigned integers
Signed integers have undesirable undefined behaviours on overflow.
Malicious compilers can turn apparently-correct code into code with
security vulnerabilities etc.

So use only unsigned integers.  Exceptions are booleans (which we have
already changed) and error codes.

We _do_ change all the chars which aren't fixed constants from our own
text segment, but not the char*s.  This is because it is safe to
access an arbitrary byte through a char*, but not necessarily safe to
convert an arbitrary value to a char.

As a consequence we need to compile libelf with -Wno-pointer-sign.

It is OK to change all the signed integers to unsigned because all the
inequalities in libelf are in contexts where we don't "expect"
negative numbers.

In libelf-dominfo.c:elf_xen_parse we rename a variable "rc" to
"more_notes" as it actually contains a note count derived from the
input image.  The "error" return value from elf_xen_parse_notes is
changed from -1 to ~0U.

grepping shows only one occurrence of "PRId" or "%d" or "%ld" in
libelf and xc_dom_elfloader.c (a "%d" which becomes "%u").

This is part of the fix to a security issue, XSA-55.

For those concerned about unintentional functional changes, the
following rune produces a version of the patch which is much smaller
and eliminates only non-functional changes:

 GIT_EXTERNAL_DIFF=.../unsigned-differ git-diff <before>..<after>

where <before> and <after> are git refs for the code before and after
this patch, and unsigned-differ is this shell script:

    #!/bin/bash
    set -e

    seddery () {
            perl -pe 's/\b(?:elf_errorstatus|elf_negerrnoval)\b/int/g'
    }

    path="$1"
    in="$2"
    out="$5"

    set +e
    diff -pu --label "$path~" <(seddery <"$in") --label "$path" <(seddery <"$out")
    rc=$?
    set -e
    if [ $rc = 1 ]; then rc=0; fi
    exit $rc

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>

v8: Use "?!?!" to express consternation instead of a ruder phrase.

v5: Introduce ELF_NOTE_INVALID, instead of using a literal ~0U.

v4: Fix regression in elf_round_up; use uint64_t here.

v3: Changes to booleans split off into separate patch.

v2: BUGFIX: Eliminate conversion to int of return from elf_xen_parse_notes.
    BUGFIX: Fix the one printf format thing which needs changing.
    Remove irrelevant change to constify note_desc.name in libelf-dominfo.c.
    In xc_dom_load_elf_symtab change one sizeof(int) to sizeof(unsigned).
    Do not change type of 2nd argument to memset.
    Provide seddery for easier review.
    Style fix.
2013-06-14 16:39:36 +01:00
Ian Jackson 7a549a6aa0 libelf: use C99 bool for booleans
We want to remove uses of "int" because signed integers have
undesirable undefined behaviours on overflow.  Malicious compilers can
turn apparently-correct code into code with security vulnerabilities
etc.

In this patch we change all the booleans in libelf to C99 bool,
from <stdbool.h>.

For the one visible libelf boolean in libxc's public interface we
retain the use of int to avoid changing the ABI; libxc converts it to
a bool for consumption by libelf.

It is OK to change all values only ever used as booleans to _Bool
(bool) because conversion from any scalar type to a _Bool works the
same as the boolean test in if() or ?: and is always defined (C99
6.3.1.2).  But we do need to check that all these variables really are
only ever used that way.  (It is theoretically possible that the old
code truncated some 64-bit values to 32-bit ints which might become
zero depending on the value, which would mean a behavioural change in
this patch, but it seems implausible that treating 0x????????00000000
as false could have been intended.)

This is part of the fix to a security issue, XSA-55.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

v3: Use <stdbool.h>'s bool (or _Bool) instead of defining elf_bool.
    Split this into a separate patch.
2013-06-14 16:39:36 +01:00
Ian Jackson c84481fbc7 libelf: Make all callers call elf_check_broken
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.
2013-06-14 16:39:36 +01:00
Ian Jackson 943de71cf0 libelf: Check pointer references in elf_is_elfbinary
elf_is_elfbinary didn't take a length parameter and could potentially
access out of range when provided with a very short image.

We only need to check the size is enough for the actual dereference in
elf_is_elfbinary; callers are just using it to check the magic number
and do their own checks (usually via the new elf_ptrval system) before
dereferencing other parts of the header.

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 a comment about the limited function of elf_is_elfbinary.

v2: Style fix.
    Fix commit message subject.
2013-06-14 16:39:36 +01:00
Ian Jackson 65808a8ed4 libelf: check all pointer accesses
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.
2013-06-14 16:39:36 +01:00
Ian Jackson 8525635999 libelf: introduce macros for memory access and pointer handling
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<-
2013-06-14 16:39:35 +01:00
Ian Jackson 95dd49bed6 libelf/xc_dom_load_elf_symtab: Do not use "syms" uninitialised
xc_dom_load_elf_symtab (with load==0) calls elf_round_up, but it
mistakenly used the uninitialised variable "syms" when calculating
dom->bsd_symtab_start.  This should be a reference to "elf".

This change might have the effect of rounding the value differently.
Previously if the uninitialised value (a single byte on the stack) was
ELFCLASS64 (ie, 2), the alignment would be to 8 bytes, otherwise to 4.

However, the value is calculated from dom->kernel_seg.vend so this
could only make a difference if that value wasn't already aligned to 8
bytes.

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: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Chuck Anderson <chuck.anderson@oracle.com>

v2: Split this change into its own patch for proper review.
2013-06-14 16:39:35 +01:00
Ian Jackson b5a8692099 libxc: Fix range checking in xc_dom_pfn_to_ptr etc.
* Ensure that xc_dom_pfn_to_ptr (when called with count==0) does not
  return a previously-allocated block which is entirely before the
  requested pfn (!)

* Provide a version of xc_dom_pfn_to_ptr, xc_dom_pfn_to_ptr_retcount,
  which provides the length of the mapped region via an out parameter.

* Change xc_dom_vaddr_to_ptr to always provide the length of the
  mapped region and change the call site in xc_dom_binloader.c to
  check it.  The call site in xc_dom_load_elf_symtab will be corrected
  in a forthcoming patch, and for now ignores the returned length.

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>

v5: This patch is new in v5 of the series.
2013-06-14 16:39:34 +01:00
David Vrabel 82639998a5 Fix emacs local variable block to use correct C style variable.
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
2013-02-21 16:12:46 +00:00
Ian Campbell e567964a54 tools: drop ia64 support
Removed support from libxc and mini-os.

This also took me under xen/include/public via various symlinks.

Dropped tools/debugger/xenitp entirely, it was described upon commit
as:
"Xenitp is a low-level debugger for ia64" and doesn't appear to be
linked into the build anywhere.

 99 files changed, 14 insertions(+), 32361 deletions(-)

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
2012-09-12 17:55:27 +01:00
Stefano Stabellini 079ff2d32c libelf-loader: introduce elf_load_image
Implement a new function, called elf_load_image, to perform the
actually copy of the elf image and clearing the padding.  The function
is implemented as memcpy and memset when the library is built as part
of the tools, but it is implemented as raw_copy_to_guest and
raw_clear_guest when built as part of Xen, so that it can be safely
called with an HVM style dom0.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
2012-01-23 09:42:12 +00:00
Keir Fraser 6bee8f6b86 elf: Fix Elf64 types and structs to match the specification.
The layouts were actually correct, but the type names were a bit
messed up.

Original patch by Volker Eckert <volker.eckert@citrix.com>
Signed-off-by: Keir Fraser <keir@xen.org>
2011-11-16 18:21:14 +00:00
Jan Beulich ec029aaa9a add privileged (dom0) kernel feature indication
With our switching away from supporting 32-bit Dom0 operation, users
complained that attempts (perhaps due to lack of knowledge of that
change) to boot the no longer privileged kernel in Dom0 resulted in
apparently silent failure. To make the mismatch explicit and visible,
add dom0 feature flag that the kernel can set to indicate operation as
dom0 is supported.

Due to the way elf_xen_parse_features() worked up to now (getting
fixed here), adding features indications to the old, string based ELF
note would make the respective kernel unusable on older hypervisors.
For that reason, a new ELF Note is being introduced that allows
specifying supported features as a bit array instead (with features
unknown to the hypervisor simply ignored, as now also done by
elf_xen_parse_features(), whereas here unknown kernel-required
features still keep the kernel [and hence VM] from booting).

Introduce and use elf_note_numeric_array() to be forward
compatible (or else an old hypervisor wouldn't be able to parse kernel
specified features occupying more than 64 bits - thanks, Ian!).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
2011-07-23 08:49:15 +01:00
Keir Fraser 71db85f478 Revert 23664:3e3c0a8be9f9 2011-07-08 13:20:09 +01:00
Jan Beulich fe15cd0fb6 add privileged/unprivileged kernel feature indication
With our switching away from supporting 32-bit Dom0 operation, users
complained that attempts (perhaps due to lack of knowledge of that
change) to boot the no longer privileged kernel in Dom0 resulted in
apparently silent failure. To make the mismatch explicit and visible,
add feature flags that the kernel can set to indicate operation in
what modes it supports. For backward compatibility, absence of both
feature flags is taken to indicate a kernel that may be capable of
operating in both modes.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
2011-07-08 08:34:29 +01:00
Ian Campbell 3e446a35ee libxc: convert evtchn interfaces to use an opaque handle type
This makes the interface consistent with the changes made to the main
interface in 21483:779c0ef9682c.

Also fix some references to "struct xc_interface" which should have
been simply "xc_interface" in tools/xenpaging, and update QEMU_TAG to
pull in the corresponding qemu change.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
2010-12-23 15:25:57 +00:00
Ian Campbell 6993e9f5ce # HG changeset patch
# User Ian Campbell <ian.campbell@citrix.com>
# Date 1282671421 -3600
# Node ID d1dd29a470ef1b9d2c77478a123326036dfe90bb
# Parent  d7a4adad9c328decbd384d87b23001aea8951b86
tools/libxc, tools/libelf: Relicense under LGPL v2.1

Relicense these two libraries under LGPL v2.1 only except where
individual files already included the "or later" provision.

Copyright holders have been contacted by Stephen Spector and have all
agreed this change.

Removed tools/libxc/ia64/aclinux.h since it appeared to be
unused. There is a separate, more up to date, copy in
xen/include/acpi/platform/aclinux.h which does appear to be used.

Clarify the license of MiniOS privcmd.h under the same terms as other
tools/include/xen-sys headers.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stephen Spector <stephen.spector@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
2010-08-24 18:42:59 +01:00
Keir Fraser 5cc436c1d2 libxc: eliminate static variables, use xentoollog; API change
This patch eliminate the global variables in libxenctrl (used for
logging and error reporting).

Instead the information which was in the global variables is now in a
new xc_interface* opaque structure, which xc_interface open returns
instead of the raw file descriptor; furthermore, logging is done via
xentoollog.

There are three new parameters to xc_interface_open to control the
logging, but existing callers can just pass "0" for all three to get
the old behaviour.

All libxc callers have been adjusted accordingly.

Also update QEMU_TAG for corresponding qemu change.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
2010-05-28 09:30:19 +01:00
Keir Fraser 36cfb6aa84 libelf: Tidy up logging and remove dependency on stdio.
libelf now permits callers to specify logging callback functions,
rather than a FILE*.  libelf's non-Xen callers are all libxc users, so
the stdio dependency and the default logging callback function (which
calls vfprintf) is now in libxc.

Xen's use of libxc is unaffected in this patch.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2010-05-28 09:27:40 +01:00
Keir Fraser 1aa3c54a31 Remove defunct powerpc port.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
2008-05-08 13:40:40 +01:00
Keir Fraser f3bf1dc168 x86: Support loading Linux bzImage v2.08 and up.
The latest -mm kernel (2.6.25-rc3-mm1) contains v2.08 of the Linux
bzImage format which embeds an ELF file in place of the raw payload
allowing it to be extracted and used by the Xen domain builder.

It is expected that this functionality will be put forward for 2.6.26.

Signed-off-by : Ian Campbell <ijc@hellion.org.uk>
2008-04-01 10:09:33 +01:00
Keir Fraser 159ce02013 libxc: Code format cleanups.
Signed-off-by: Keir Fraser <keir@xensource.com>
2007-02-24 15:30:19 +00:00
Emmanuel Ackaouy b4feb14b3d libxc domain builder rewrite, core bits.
Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
---
 tools/libxc/Makefile           |   14
 tools/libxc/xc_dom.h           |  261 +++++++++++++
 tools/libxc/xc_dom_binloader.c |  294 +++++++++++++++
 tools/libxc/xc_dom_boot.c      |  515 +++++++++++++++++++++++++++
 tools/libxc/xc_dom_core.c      |  773 +++++++++++++++++++++++++++++++++++++++++
 tools/libxc/xc_dom_elfloader.c |  283 +++++++++++++++
 tools/libxc/xc_dom_ia64.c      |  118 ++++++
 tools/libxc/xc_dom_powerpc64.c |  100 +++++
 tools/libxc/xc_dom_x86.c       |  559 +++++++++++++++++++++++++++++
 9 files changed, 2917 insertions(+)
2007-01-25 22:16:52 +00:00