Commit Graph

58 Commits

Author SHA1 Message Date
Kevin Enderby 86d8bd1da5 Fix a typo in an error message for a check of invalid Mach-O files where
it was printing the field name fileoff instead of filesize.  The original check
was added in r278557.

This was found in tracking down the problem that lead to the fix in
r293842 - [dsymutil] Fix __LINKEDIT vmsize in dsymutil upgrade path

rdar://30386075

llvm-svn: 294354
2017-02-07 21:20:44 +00:00
Kevin Enderby 98898f2b02 Change the llvm-obdump(1) behavior with the -macho flag and inappropriate file types.
To better match the old darwin otool(1) behavior, when llvm-obdump(1) is used
with the -macho option and the input file is not an object file simply print
the file name and this message:

foo: is not an object file

and continue on to process other input files.  Also in this case don’t exit
non-zero.  This should help in some OSS projects' with autoconf scripts
that are expecting the old darwin otool(1) behavior.

rdar://26828015

llvm-svn: 293547
2017-01-30 20:53:17 +00:00
Kevin Enderby a4579c4184 Add support for the new LC_NOTE load command.
It describes a region of arbitrary data included in a Mach-O file.
Its initial use is to record extra data in MH_CORE files.

rdar://30001545
rdar://30001731

llvm-svn: 292500
2017-01-19 17:36:31 +00:00
Kevin Enderby 4ffec859eb Add error checking for Mach-O universal files.
Add the checking for both the MachO::fat_header and the
MachO::fat_arch struct values in the constructor for
MachOUniversalBinary. Such that when the constructor
for ObjectForArch is called it can assume the values in
the MachO::fat_arch for the offset and size are contained
in the file after the MachOUniversalBinary constructor
is called for the Parent.

llvm-svn: 288084
2016-11-28 22:40:50 +00:00
Kevin Enderby fbebe1632a Add the rest of the additional error checks for invalid Mach-O files when
the offsets and sizes of an element of the Mach-O file overlaps with
another element in the Mach-O file.

Some other tests for malformed Mach-O files now run into these
checks so their tests were also adjusted.

llvm-svn: 285860
2016-11-02 21:08:39 +00:00
Kevin Enderby d503940e8f More additional error checks for invalid Mach-O files when
the offsets and sizes of an element of the file overlaps with
another element in the Mach-O file.

This shows the approach to this testing for three elements
and contains for tests for their overlap.  Checking for all the
remain elements will be added next.

llvm-svn: 285632
2016-10-31 20:29:48 +00:00
Kevin Enderby bc5c29a65f Another additional error check for invalid Mach-O files for the
obsolete load commands.

Again the philosophy of the error checking in libObject for
Mach-O files, the idea behind the checking is that we never
will return a Mach-O file out of libObject that contains unknown
things the library code can’t operate on.  So known obsolete
load commands will cause a hard error.

Also to make things clear I have added comments to the
values and structures in Support/Mach-O.h and
Support/MachO.def as to what is obsolete.

As noted in a TODO in the code, there may need to be a
non-default mode to allow some unknown values for well
structured Mach-O files with things like unknown load
load commands.  So things like using an old lldb on a newer
Mach-O file could still provide some limited functionality.

llvm-svn: 285342
2016-10-27 20:59:10 +00:00
Justin Bogner 31d8b7d21d llvm-objdump: Make some error messages more consistent
Most of the version of report_error were quoting the filename and
printing a colon between the file name and the error message, but this
one wasn't doing either of those. Fix the output to be more
consistent.

llvm-svn: 285252
2016-10-26 22:37:52 +00:00
Kevin Enderby 79d6c63f61 nother additional error check for an invalid Mach-O file
when contained in a Mach-O universal file and the
cputypes in both headers don’t match.

llvm-svn: 285026
2016-10-24 21:15:11 +00:00
Kevin Enderby c8bb42283e Another additional error check for invalid Mach-O files for the
load commands that use the MachO::twolevel_hints_command type
which includes only the LC_TWOLEVEL_HINTS load command.

This is not used in llvm libObject code or in llvm tool code.  But
does appear in one of the binary test files.  While this load command is
obsolete it is easier to add code for it in libObject than edit or change
the binary test case.

llvm-svn: 284769
2016-10-20 20:10:30 +00:00
Kevin Enderby 210030ba95 Next set of additional error checks for invalid Mach-O files for the
load commands that use the MachO::thread_command type
but are not used in llvm libObject code but used in llvm tool code.

This includes the LC_UNIXTHREAD and LC_THREAD
load commands.

A quick note about the philosophy of the error checking in
libObject for Mach-O files, the idea behind the checking is
that we never will return a Mach-O file out of libObject that
contains unknown things in the load commands.

To do this the 32-bit ARM and PPC general tread states
needed to be defined as two test case binaries contained
them.  If other thread states for other CPUs need to be
added we will do that as needed.

Going forward the LC_MAIN load command is used to
set the entry point in Mach-O executables these days
instead of an LC_UNIXTHREAD as was done in the past.
So today only in core files are LC_THREAD load commands
and thread states usually found.

Other thread states have not yet been defined in
include/Support/MachO.h at this time.  But that can be
added as needed with their corresponding checking also
added.

llvm-svn: 284668
2016-10-19 23:44:34 +00:00
Kevin Enderby 89baf99c92 One more additional error check for invalid Mach-O files for a
load command that use the MachO:: linkedit_data_command
type but is not used in llvm libObject code but used in llvm tool code.

This is for the LC_CODE_SIGNATURE load command.

llvm-svn: 284529
2016-10-18 20:24:12 +00:00
Kevin Enderby 6f69582e9b Next set of additional error checks for invalid Mach-O files for the
load commands that use the MachO::routines_command and
and MachO::routines_command_64 types but are not used in llvm
libObject code but used in llvm tool code.

This includes the LC_ROUTINES and LC_ROUTINES_64
load commands.

llvm-svn: 284504
2016-10-18 17:54:17 +00:00
Kevin Enderby 2490de06f7 Next set of additional error checks for invalid Mach-O files for the
load commands that use the MachO::sub_framework_command,
MachO::sub_umbrella_command, MachO::sub_library_command
and MachO::sub_client_command types but are not used in llvm
libObject code but used in llvm tool code.

This includes the LC_SUB_FRAMEWORK, LC_SUB_UMBRELLA,
LC_SUB_LIBRARY and LC_SUB_CLIENT load commands.

llvm-svn: 284431
2016-10-17 22:09:25 +00:00
Kevin Enderby 68fffa8a62 Next set of additional error checks for invalid Mach-O files for the
load commands that uses the MachO::linker_option_command
type but not used in llvm libObject code but used in llvm tool code.

This includes just LC_LINKER_OPTION load command.

llvm-svn: 283939
2016-10-11 21:04:39 +00:00
Kevin Enderby f993d6e72c Next set of additional error checks for invalid Mach-O files for the
load commands that uses the MachO::encryption_info_command and
MachO::encryption_info_command types but not used in llvm libObject
code but used in llvm tool code.

This includes just LC_ENCRYPTION_INFO and
LC_ENCRYPTION_INFO_64 load commands.

llvm-svn: 283250
2016-10-04 20:37:43 +00:00
Kevin Enderby 4f229d867b Next set of additional error checks for invalid Mach-O files for the
load command that uses the MachO::entry_point_command type
but not used in llvm libObject code but used in llvm tool code.

This includes just the LC_MAIN load command.

llvm-svn: 282766
2016-09-29 21:07:29 +00:00
Kevin Enderby 245be3ed2a Next set of additional error checks for invalid Mach-O files for the
load command that uses the Mach::source_version_command type
but not used in llvm libObject code but used in llvm tool code.

This includes just the LC_SOURCE_VERSION load command.

llvm-svn: 282736
2016-09-29 17:45:23 +00:00
Kevin Enderby 76966bf066 Next set of additional error checks for invalid Mach-O files for the
load command that uses the Mach::rpath_command type
but not used in llvm libObject code but used in llvm tool code.

This includes just the LC_RPATH load command.

llvm-svn: 282649
2016-09-28 23:16:01 +00:00
Kevin Enderby 32359dbf6b Next set of additional error checks for invalid Mach-O files for the
other load commands that use the Mach::version_min_command type
but not used in llvm libObject code but used in llvm tool code.

This includes LC_VERSION_MIN_MACOSX, LC_VERSION_MIN_IPHONEOS,
LC_VERSION_MIN_TVOS and LC_VERSION_MIN_WATCHOS load commands.

llvm-svn: 282635
2016-09-28 21:20:45 +00:00
Kevin Enderby 3e490ef94e Next set of additional error checks for invalid Mach-O files for the
other load commands that use the MachO::dylinker_command type
but not used in llvm libObject code but used in llvm tool code.

This includes LC_ID_DYLINKER, LC_LOAD_DYLINKER
and LC_DYLD_ENVIRONMENT load commands.

llvm-svn: 282553
2016-09-27 23:24:13 +00:00
Kevin Enderby 90986e6c7c Next set of additional error checks for invalid Mach-O files for the
other load commands that use the Mach::linkedit_data_command type
but not used in llvm libObject code but used in llvm tool code.

This includes LC_FUNCTION_STARTS, LC_SEGMENT_SPLIT_INFO
and LC_DYLIB_CODE_SIGN_DRS load commands.

llvm-svn: 282441
2016-09-26 21:11:03 +00:00
Kevin Enderby e71e13c7d6 Next set of additional error checks for invalid Mach-O files for bad LC_UUID
load commands.  Added a missing check and made the check for more than
one like other other “more than one” checks.  And of course added test cases.

llvm-svn: 282104
2016-09-21 20:03:09 +00:00
Kevin Enderby fc0929adb8 Next set of additional error checks for invalid Mach-O files for bad load commands
that use the Mach::dylib_command type for the load commands that are
currently used in the MachOObjectFile constructor.

This contains the missing checks for LC_ID_DYLIB, LC_ID_DYLIB, etc.
load commands and the fields for the Mach::dylib_command type.

Also checks that only an MH_DYLIB or MH_STUB_DYLIB has an
LC_ID_DYLIB load command (and others filetype don’t) and there
is not more than one of these load commands.

llvm-svn: 282008
2016-09-20 20:14:14 +00:00
Kevin Enderby f76b56cb9c Next set of additional error checks for invalid Mach-O files for bad load commands
that use the Mach::dyld_info_command type for the load commands that are
currently use in the MachOObjectFile constructor.

This contains the missing checks for LC_DYLD_INFO and
LC_DYLD_INFO_ONLY load commands and the fields for the
Mach::dyld_info_command type.

llvm-svn: 281400
2016-09-13 21:42:28 +00:00
Kevin Enderby 9d0c945ad6 Next set of additional error checks for invalid Mach-O files for bad load commands
that use the Mach::linkedit_data_command type for the load commands that are
currently used in the MachOObjectFile constructor.

This contains the missing checks for LC_DATA_IN_CODE and
LC_LINKER_OPTIMIZATION_HINT load commands and the fields for the
Mach::linkedit_data_command type.  Checking for other load commands that
use this type will be added later.

Also fixed a couple of places that was using sizeof(MachOObjectFile::LoadCommandInfo)
that should have been using sizeof(MachO::load_command).

llvm-svn: 280267
2016-08-31 17:57:46 +00:00
Kevin Enderby dcbc504c47 Next set of additional error checks for invalid Mach-O files for bad LC_DYSYMTAB’s.
This contains the missing checks for LC_DYSYMTAB load command fields.

llvm-svn: 280161
2016-08-30 21:28:30 +00:00
Kevin Enderby 0e52c92e22 Next set of additional error checks for invalid Mach-O files for bad LC_SYMTAB’s.
This contains the missing checks for LC_SYMTAB load command fields.

llvm-svn: 279854
2016-08-26 19:34:07 +00:00
Kevin Enderby c614d283b7 Next set of additional error checks for invalid Mach-O files.
This contains the two missing checks for LC_SEGMENT load command fields.
And checks for the Mach-O sections fields that would make them invalid.

With the new checks, some of the existing malformed file checks now trips one
of these instead of the issue it was having before so those tests were adjusted.

llvm-svn: 278557
2016-08-12 20:10:25 +00:00
Kevin Enderby 600fb3f28e Add the first of what will be a long line of additional error checks for invalid Mach-O files.
This is where an LC_SEGMENT load command has a fileoff field that
extends past the end of the file.

Also fix llvm-nm and llvm-size to remove the errorToErrorCode() call so error messages are printed.
And needed to update a few test cases now that they do print the error messages just a
bit differently.

llvm-svn: 277845
2016-08-05 18:19:40 +00:00
Kevin Enderby 1851a827a0 Add checks to the MachOObjectFile() constructor to make sure load commands sizes
are the correct multiple.

llvm-svn: 274798
2016-07-07 22:11:42 +00:00
Kevin Enderby 42398051d8 Finish cleaning up most of the error handling in libObject’s MachOUniversalBinary
and its clients to use the new llvm::Error model for error handling.

Changed getAsArchive() from ErrorOr<...> to Expected<...> so now all
interfaces there use the new llvm::Error model for return values.

In the two places it had if (!Parent) this is actually a program error so changed
from returning errorCodeToError(object_error::parse_failed) to calling
report_fatal_error() with a message.

In getObjectForArch() added error messages to its two llvm::Error return values
instead of returning errorCodeToError(object_error::arch_not_found) with no
error message.

For the llvm-obdump, llvm-nm and llvm-size clients since the only binary files in
Mach-O Universal Binaries that are supported are Mach-O files or archives with
Mach-O objects, updated their logic to generate an error when a slice contains
something like an ELF binary instead of ignoring it. And added a test case for
that.

The last error stuff to be cleaned up for libObject’s MachOUniversalBinary is
the use of errorOrToExpected(Archive::create(ObjBuffer)) which needs
Archive::create() to be changed from ErrorOr<...> to Expected<...> first,
which I’ll work on next. 

llvm-svn: 274079
2016-06-28 23:16:13 +00:00
Kevin Enderby 1051909df1 Change all but the last ErrorOr<...> use for MachOUniversalBinary to Expected<...> to
allow a good error message to be produced.

I added the one test case that the object file tools could produce an error
message.  The other two errors can’t be triggered if the input file is passed
through sys::fs::identify_magic().  But the malformedError("bad magic number")
does get triggered by the logic in llvm-dsymutil when dealing with a normal
Mach-O file.  The other "File too small ..." error would take a logic error
currently to produce and is not tested for.

llvm-svn: 273946
2016-06-27 21:39:39 +00:00
Kevin Enderby 9acb109930 Change llvm-objdump, llvm-nm and llvm-size when reporting an object file error
when the object is from a slice of a Mach-O Universal Binary use something like
"foo.o (for architecture i386)" as part of the error message when expected.

Also fixed places in these tools that were ignoring object file errors from
MachOUniversalBinary::getAsObjectFile() when the code moved on to see if
the slice was an archive.

To do this MachOUniversalBinary::getAsObjectFile() and
MachOUniversalBinary::getObjectForArch() were changed from returning
ErrorOr<...> to Expected<...> then that was threaded up to its users.

Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now the use of
errorToErrorCode() is still used in two places yet to be fully converted.

llvm-svn: 271332
2016-05-31 20:35:34 +00:00
Kevin Enderby ac9e15551d Change llvm-objdump, llvm-nm and llvm-size when reporting an object file error
when the object is in an archive to use something like libx.a(foo.o) as part of
the error message.

Also changed llvm-objdump and llvm-size to be like llvm-nm and ignore non-object
files in archives and not produce any error message.

To do this Archive::Child::getAsBinary() was changed from ErrorOr<...> to
Expected<...> then that was threaded up to its users.

Converting this interface to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now the use of
errorToErrorCode() is still used in one place yet to be fully converted.

Again there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comments for those.

llvm-svn: 269784
2016-05-17 17:10:12 +00:00
Kevin Enderby b34e3a1877 Clean up the specific error message for a malformed Mach-O files with bad segment
load commands.

The existing test case in test/Object/macho-invalid.test for
macho-invalid-too-small-segment-load-command has a cmdsize of 55, while
being too small also it is not a multiple of 4.  So when that check is added
this test case will produce a different error. So I constructed a new test case
that will trigger the intended error.

I also changed the error message to be consistent with the other malformed Mach-O
file error messages which prints the load command index.  I also removed both
object_error::macho_load_segment_too_small and
object_error::macho_load_segment_too_many_sections from Object/Error.h
as they are not needed and can just use object_error::parse_failed and let the
error message string distinguish the specific error.

llvm-svn: 268652
2016-05-05 17:43:35 +00:00
Kevin Enderby a8e3ab0c56 Produce another specific error message for a malformed Mach-O file when a load
command has a size less than 8 bytes.

I think the existing test case in test/Object/macho-invalid.test for
macho64-invalid-too-small-load-command was trying to test for this but that
test case triggered a different error given how it was constructed.  So I
constructed a new test case that would trigger this specific error.

I also changed the error message to be consistent with the other malformed Mach-O
file error messages.  I also removed object_error::macho_small_load_command from
Object/Error.h as it is not needed and can just use object_error::parse_failed
and let the error message string distinguish the error.

llvm-svn: 268463
2016-05-03 23:13:50 +00:00
Kevin Enderby 368e714907 Produce another specific error message for a malformed Mach-O file when a load
command other than the first one is past the end of the load commands.

This is like the test case in test/Object/macho-invalid.test for
macho64-invalid-incomplete-load-command but it is the second load command
that is past the end of all the load commands instead of the first.

The code in the constructor for MachOObjectFile that loops over the load
commands used getNextLoadCommandInfo() which was not producing
a good error message.  So that was fixed and a test case was added.

llvm-svn: 268403
2016-05-03 17:16:08 +00:00
Kevin Enderby 7bd8d99497 Thread Expected<...> up from libObject’s getType() for symbols to allow llvm-objdump to produce a good error message.
Produce another specific error message for a malformed Mach-O file when a symbol’s
section index is more than the number of sections.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-section-index-getSectionRawName now reports the error with the message indicating
that a symbol at a specific index has a bad section index and that bad section index value.

Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
"// TODO: Actually report errors helpfully" and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

llvm-svn: 268298
2016-05-02 20:28:12 +00:00
Kevin Enderby 6e295f2304 Fix a typo in an error message. Caught by Sean Silva!
llvm-svn: 267056
2016-04-21 21:20:40 +00:00
Kevin Enderby 81e8b7d949 Thread Expected<...> up from libObject’s getName() for symbols to allow llvm-objdump to produce a good error message.
Produce another specific error message for a malformed Mach-O file when a symbol’s
string index is past the end of the string table.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-symbol-name-past-eof now reports the error with the message indicating
that a symbol at a specific index has a bad sting index and that bad string index value.
 
Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same.  There is some
code for this that could be factored into a routine but I would like to leave that for
the code owners post-commit to do as they want for handling an llvm::Error.  An
example of how this could be done is shown in the diff in
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h which had a Check() routine
already for std::error_code so I added one like it for llvm::Error .

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there fixes needed to lld that goes along with this that I will commit right after this.
So expect lld not to built after this commit and before the next one.

llvm-svn: 266919
2016-04-20 21:24:34 +00:00
Kevin Enderby 8702574557 Start to add real error messages for malformed Mach-O files.
And update the existing test cases in test/Object/macho-invalid.test
to use llvm-objdump with the -macho option to produce these
error messages and stop producing the generic "Invalid data
was encountered while parsing the file" message.

Working from the beginning of the file, if the mach header is too large for
the size of the file and then if the load commands that follow extend past
the end of the file these two errors now generate correct error messages.

Both of these have existing test cases in test/Object/macho-invalid.test .

But the first with macho-invalid-header it will never trigger the error message
"mach header extends past the end of the file" using any of the llvm tools as
they all use identify_magic() which rejects files with the correct magic number
that are too small in size.  So I tested this by hacking that code and seeing the
error message down in parseHeader() really does happen.  So in case there
is ever code in llvm that directly calls createMachOObjectFile() this error
message will be correctly produced.

The second error message of "load commands extends past the end of the file"
is triggered by a number of existing tests cases in test/Object/macho-invalid.test .
Also other tests trigger different error messages now like "ilocalsym plus
nlocalsym in LC_DYSYMTAB load command extends past the end of the
symbol table".

There are two existing test cases that still get the "Invalid data was encountered ..."
error messages that I will tackle next.  But they will involve a bit of pluming an
Expect<...> up through the call stack and I want to do those as separate changes.

FYI, for those test cases that were trying to test specific errors that now get
different errors I’ll fix those in follow on changes and create new test cases
for those so they test the error they were meant to test.

llvm-svn: 266248
2016-04-13 21:17:58 +00:00
Kevin Enderby 3fcdf6ae2a Thread Expected<...> up from createMachOObjectFile() to allow llvm-objdump to produce a real error message
Produce the first specific error message for a malformed Mach-O file describing
the problem instead of the generic message for object_error::parse_failed of
"Invalid data was encountered while parsing the file”.  Many more good error
messages will follow after this first one.

This is built on Lang Hames’ great work of adding the ’Error' class for
structured error handling and threading Error through MachOObjectFile
construction.  And making createMachOObjectFile return Expected<...> .

So to to get the error to the llvm-obdump tool, I changed the stack of
these methods to also return Expected<...> :

  object::ObjectFile::createObjectFile()
  object::SymbolicFile::createSymbolicFile()
  object::createBinary()

Then finally in ParseInputMachO() in MachODump.cpp the error can
be reported and the specific error message can be printed in llvm-objdump
and can be seen in the existing test case for the existing malformed binary
but with the updated error message.

Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now use of
errorToErrorCode() and errorOrToExpected() are used where the callers
are yet to be converted.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(ObjOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there is one fix also needed to lld/COFF/InputFiles.cpp that goes along
with this that I will commit right after this.  So expect lld not to built
after this commit and before the next one.

llvm-svn: 265606
2016-04-06 22:14:09 +00:00
Kevin Enderby 5afbc1cda7 Fix a crash in running llvm-objdump -t with an invalid Mach-O file already
in the test suite. While this is not really an interesting tool and option to run
on a Mach-O file to show the symbol table in a generic libObject format
it shouldn’t crash.

The reason for the crash was in MachOObjectFile::getSymbolType() when it was
calling MachOObjectFile::getSymbolSection() without checking its return value
for the error case.

What makes this fix require a fair bit of diffs is that the method getSymbolType() is
in the class ObjectFile defined without an ErrorOr<> so I needed to add that all
the sub classes.  And all of the uses needed to be updated and the return value
needed to be checked for the error case.

The MachOObjectFile version of getSymbolType() “can” get an error in trying to
come up with the libObject’s internal SymbolRef::Type when the Mach-O symbol
symbol type is an N_SECT type because the code is trying to select from the
SymbolRef::ST_Data or SymbolRef::ST_Function values for the SymbolRef::Type.
And it needs the Mach-O section to use isData() and isBSS to determine if
it will return SymbolRef::ST_Data.

One other possible fix I considered is to simply return SymbolRef::ST_Other
when MachOObjectFile::getSymbolSection() returned an error.  But since in
the past when I did such changes that “ate an error in the libObject code” I
was asked instead to push the error out of the libObject code I chose not
to implement the fix this way.

As currently written both the COFF and ELF versions of getSymbolType()
can’t get an error.  But if isReservedSectionNumber() wanted to check for
the two known negative values rather than allowing all negative values or
the code wanted to add the same check as in getSymbolAddress() to use
getSection() and check for the error then these versions of getSymbolType()
could return errors.

At the end of the day the error printed now is the generic “Invalid data was
encountered while parsing the file” for object_error::parse_failed.  In the
future when we thread Lang’s new TypedError for recoverable error handling
though libObject this will improve.  And where the added // Diagnostic(…
comment is, it would be changed to produce and error message
like “bad section index (42) for symbol at index 8” for this case.

llvm-svn: 264187
2016-03-23 20:27:00 +00:00
Kevin Enderby 87c85b7e23 Fix identify_magic() to check that a file that starts with MH_MAGIC is
at least as big as the mach header to be identified as a Mach-O file and
make sure smaller files are not identified as a Mach-O files but as
unknown files. Also fix identify_magic() so it looks at all 4 bytes of
the filetype field when determining the type of the Mach-O file.
Then fix the macho-invalid-header test case to check that it is an
unknown file and make sure it does not get the error for
object_error::parse_failed.  And also update the unit tests.

llvm-svn: 258883
2016-01-26 23:43:37 +00:00
Kevin Enderby 40fdbf87d2 Update the comments for the macho-invalid-zero-ncmds test and fix
llvm-objdump when printing the Mach Header to print the unknown
cputype and cpusubtype fields as decimal instead of not printing
them at all.  And change the test to check for that.

llvm-svn: 258826
2016-01-26 18:20:49 +00:00
Kevin Enderby 1829c686bf Fix the code that leads to the incorrect trigger of the report_fatal_error()
in MachOObjectFile::getSymbolByIndex() when a Mach-O file has
a symbol table load command but the number of symbols are zero.

The code in MachOObjectFile::symbol_begin_impl() should not be
assuming there is a symbol at index 0, in cases there is no symbol
table load command or the count of symbol is zero.  So I also fixed
that.  And needed to fix MachOObjectFile::symbol_end_impl() to
also do the same thing for no symbol table or one with zero entries.

The code in MachOObjectFile::getSymbolByIndex() should trigger
the report_fatal_error() for programmatic errors for any index when
there is no symbol table load command and not return the end iterator.
So also fixed that. Note there is no test case as this is a programmatic
error.

The test case using the file macho-invalid-bad-symbol-index has
a symbol table load command with its number of symbols (nsyms)
is zero. Which was incorrectly testing the bad triggering of the
report_fatal_error() in in MachOObjectFile::getSymbolByIndex().

This test case is an invalid Mach-O file but not for that reason.
It appears this Mach-O file use to have an nsyms value of 11,
and what makes this Mach-O file invalid is the counts and
indexes into the symbol table of the dynamic load command
are now invalid because the number of symbol table entries
(nsyms) is now zero.  Which can be seen with the existing
llvm-obdump:

% llvm-objdump -private-headers macho-invalid-bad-symbol-index
…
Load command 4
     cmd LC_SYMTAB
 cmdsize 24
  symoff 4216
   nsyms 0
  stroff 4392
 strsize 144
Load command 5
            cmd LC_DYSYMTAB
        cmdsize 80
      ilocalsym 0
      nlocalsym 8 (past the end of the symbol table)
     iextdefsym 8 (greater than the number of symbols)
     nextdefsym 2 (past the end of the symbol table)
      iundefsym 10 (greater than the number of symbols)
      nundefsym 1 (past the end of the symbol table)
...

And the native darwin tools generates an error for this file:

% nm macho-invalid-bad-symbol-index
nm: object: macho-invalid-bad-symbol-index truncated or malformed object (ilocalsym plus nlocalsym in LC_DYSYMTAB load command extends past the end of the symbol table)

I added new checks for the indexes and sizes for these in the
constructor of MachOObjectFile.  And added comments for what
would be a proper diagnostic messages.

And changed the test case using macho-invalid-bad-symbol-index
to test for the new error now produced.

Also added a test with a valid Mach-O file with a symbol table
load command where the number of symbols is zero that shows
the report_fatal_error() is not called.

llvm-svn: 258576
2016-01-22 22:49:55 +00:00
Kevin Enderby f681ec5db1 Fix MachOObjectFile::getSymbolName() to not call report_fatal_error()
but to return object_error::parse_failed.  Then made the code in llvm-nm
do for Mach-O files what is done in the darwin native tools which is to
print "bad string index" for bad string indexes.  Updated the error message
in the llvm-objdump test, and added tests to show llvm-nm prints
"bad string index" and a test to print the actual bad string index value
which in this case is 0xfe000002 when printing the fields as raw hex.

llvm-svn: 258520
2016-01-22 18:47:14 +00:00
Kevin Enderby 1f472eace5 Fix MachOObjectFile::getSymbolSection() to not call report_fatal_error()
but to return object_error::parse_failed.  Then made the code in llvm-nm
do for Mach-O files what is done in the darwin native tools which is to
print "(?,?)" or just "s" for bad section indexes.  Also added a test to show
it prints the bad section index of "42" when printing the fields as raw hex.

llvm-svn: 258434
2016-01-21 21:13:27 +00:00
Alexey Samsonov f8a7bf8c6e [Object, MachO] Don't crash on incomplete MachO segment load commands.
Report proper error code from MachOObjectFile constructor if we
can't parse another segment load command (we already return a proper
error if segment load command contents is suspicious).

llvm-svn: 239109
2015-06-04 22:26:44 +00:00