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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Summary:
Properly report the error in segment load commands from MachOObjectFile
constructor instead of crashing the program.
Adjust the test case accordingly.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
llvm-svn: 239081
Summary:
Currently all load commands are parsed in MachOObjectFile constructor.
If the next load command cannot be parsed, or if command size is too
small, properly report it through the error code and fail to construct
the object, instead of crashing the program.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
llvm-svn: 239080
Summary: Instead, properly report this error from MachOObjectFile constructor.
Test Plan: regression test suite
Reviewers: rafael
Subscribers: llvm-commits
llvm-svn: 239078
MachO and COFF quite reasonably only define the size for common symbols.
We used to try to figure out the "size" by computing the gap from one symbol to
the next.
This would not be correct in general, since a part of a section can belong to no
visible symbol (padding, private globals).
It was also really expensive, since we would walk every symbol to find the size
of one.
If a caller really wants this, it can sort all the symbols once and get all the
gaps ("size") in O(n log n) instead of O(n^2).
On MachO this also has the advantage of centralizing all the checks for an
invalid n_sect.
llvm-svn: 238028
Summary:
Shift an older “invalid file” test to get a consistent naming for these tests.
Bugs found by afl-fuzz
Reviewers: rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6945
llvm-svn: 226219
Kevin Enderby