`struct Elf*_Shdr` has a field `sh_offset`, named `ShOffset` in
llvm::ELFYAML::Section. Rename SHOffset (e_shoff) to SHOff to prevent confusion.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67254
llvm-svn: 371185
Linkers (ld.bfd/gold/lld) place the section header table at the very
end. This allows tools to strip it, which is optional in executable/shared objects.
In addition, if we add or section, the size of the section header table
will change. Placing the section header table in the end keeps section
offsets unchanged.
yaml2obj currently places the section header table immediately after the
program header. Follow what linkers do to make offset updating easier.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67221
llvm-svn: 371074
When we have a dynamic relocation with a broken symbol's st_name,
tools report a useless error: "Invalid data was encountered while parsing the file".
After this change we report a warning + "<corrupt>" as a symbol name.
Differential revision: https://reviews.llvm.org/D66734
llvm-svn: 370330
Fix: Add a `consumeError` call removed by mistake to 'printStackSize',
this should fix the "Expected<T> must be checked before access or destruction." reported by following bot:
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/9743/steps/stage%201%20check/logs/stdio
Original commit message:
Currently we have the following functions for error reporting:
LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg);
void reportError(Error Err, StringRef Input);
void reportWarning(Twine Msg);
void reportWarning(StringRef Input, Error Err);
void warn(llvm::Error Err);
void error(std::error_code EC);
Problems are: naming is inconsistent, arguments order is inconsistent,
some of the functions looks excessive.
After applying this patch we have:
void reportError(Error Err, StringRef Input);
void reportError(std::error_code EC, StringRef Input);
void reportWarning(Error Err, StringRef Input);
I'd be happy to remove reportError(std::error_code EC, StringRef Input) too, but it
is used by COFF heavily.
Test cases were updated, they show an improvement introduced.
Differential revision: https://reviews.llvm.org/D66286
llvm-svn: 369194
urrently we have the following functions for error reporting:
--
LLVM_ATTRIBUTE_NORETURN void reportError(Twine Msg);
void reportError(Error Err, StringRef Input);
void reportWarning(Twine Msg);
void reportWarning(StringRef Input, Error Err);
void warn(llvm::Error Err);
void error(std::error_code EC);
---
Problems are: naming is inconsistent, arguments order is inconsistent,
some of the functions looks excessive.
After applying this patch we have:
---
LLVM_ATTRIBUTE_NORETURN void reportError(Error Err, StringRef Input);
LLVM_ATTRIBUTE_NORETURN void reportError(std::error_code EC, StringRef Input);
void reportWarning(Error Err, StringRef Input);
---
I'd be happy to remove reportError(std::error_code EC, StringRef Input) too, but it
is used by COFF heavily.
Test cases were updated, they show an improvement introduced.
Differential revision: https://reviews.llvm.org/D66286
llvm-svn: 369190
Changes: no changes. A fix for the clang code will be landed right on top.
Original commit message:
SectionRef::getName() returns std::error_code now.
Returning Expected<> instead has multiple benefits.
For example, it forces user to check the error returned.
Also Expected<> may keep a valuable string error message,
what is more useful than having a error code.
(Object\invalid.test was updated to show the new messages printed.)
This patch makes a change for all users to switch to Expected<> version.
Note: in a few places the error returned was ignored before my changes.
In such places I left them ignored. My intention was to convert the interface
used, and not to improve and/or the existent users in this patch.
(Though I think this is good idea for a follow-ups to revisit such places
and either remove consumeError calls or comment each of them to clarify why
it is OK to have them).
Differential revision: https://reviews.llvm.org/D66089
llvm-svn: 368826
SectionRef::getName() returns std::error_code now.
Returning Expected<> instead has multiple benefits.
For example, it forces user to check the error returned.
Also Expected<> may keep a valuable string error message,
what is more useful than having a error code.
(Object\invalid.test was updated to show the new messages printed.)
This patch makes a change for all users to switch to Expected<> version.
Note: in a few places the error returned was ignored before my changes.
In such places I left them ignored. My intention was to convert the interface
used, and not to improve and/or the existent users in this patch.
(Though I think this is good idea for a follow-ups to revisit such places
and either remove consumeError calls or comment each of them to clarify why
it is OK to have them).
Differential revision: https://reviews.llvm.org/D66089
llvm-svn: 368812
This patch changes the code to use a modern unwrapOrError(StringRef Input, Expected<T> EO)
version that contains the input source name and removes the deprecated version.
Differential revision: https://reviews.llvm.org/D65946
llvm-svn: 368428
In some cases a symbol might have section index == SHN_XINDEX.
This is an escape value indicating that the actual section header index
is too large to fit in the containing field.
Then the SHT_SYMTAB_SHNDX section is used. It contains the 32bit values
that stores section indexes.
ELF gABI says that there can be multiple SHT_SYMTAB_SHNDX sections,
i.e. for example one for .symtab and one for .dynsym
(1) https://groups.google.com/forum/#!topic/generic-abi/-XJAV5d8PRg
(2) DT_SYMTAB_SHNDX: http://www.sco.com/developers/gabi/latest/ch5.dynamic.html
In this patch I am only supporting a single SHT_SYMTAB_SHNDX associated
with a .symtab. This is a more or less common case which is used a few tests I saw in LLVM.
I decided not to create the SHT_SYMTAB_SHNDX section as "implicit",
but implement is like a kind of regular section for now.
i.e. tools do not recreate this section or its content, like they do for
symbol table sections, for example. That should allow to write all kind of
possible broken test cases for our needs and keep the output closer to requested.
Differential revision: https://reviews.llvm.org/D65446
llvm-svn: 368272
Currently, we have a code duplication in llvm-readobj which was introduced in D63266.
The duplication was introduced to allow llvm-readobj to dump the partially
broken object. Methods in ELFFile<ELFT> perform a strict validation of the inputs,
what is itself good, but not for dumper tools, that might want to dump the information,
even if some pieces are broken/unexpected.
This patch introduces a warning handler which can be passed to ELFFile<ELFT> methods
and can allow skipping the non-critical errors when needed/possible.
For demonstration, I removed the duplication from llvm-readobj and implemented a warning using
the new custom warning handler. It also deduplicates the strings printed, making the output less verbose.
Differential revision: https://reviews.llvm.org/D65515
llvm-svn: 368260
When e_shstrndx is equal to SHN_XINDEX,
the index of the section string table section should
be taken from the sh_link field of the section
header at index 0.
If sh_link is broken, e.g. contains an index that is
larger than number of sections, then error is reported.
This error message was untested before.
Differential revision: https://reviews.llvm.org/D65391
llvm-svn: 368139
This allows to write a test case for one of untested errors
in llvm/Object/ELF.h.
I did it in this patch to demonstrate.
Differential revision: https://reviews.llvm.org/D65394
llvm-svn: 367860
This error was never tested. In this patch I improved
the error message, added the test case and also simplified
the code that processes a similar error right below.
Differential revision: https://reviews.llvm.org/D65396
llvm-svn: 367391
With a fix of the issue found by UBSan.
Original commit message:
This eliminates a one error untested and
also introduces a error for one more possible case
which lead to crash previously.
Differential revision: https://reviews.llvm.org/D64987
llvm-svn: 366886
This eliminates a one error untested and
also introduces a error for one more possible case
which lead to crash previously.
Differential revision: https://reviews.llvm.org/D64987
llvm-svn: 366796
When e_shstrndx is broken, it is impossible to get a section name.
In this patch I improved the error message we show and
added tests for Object and for llvm-readelf/llvm-readobj
Message was changed in two places:
1) llvm-readelf/llvm-readobj previously used a code from Object/ELF.h,
now they have a modified version of it (it has less checks and allows
dumping broken things).
2) Code in Object/ELF.h is still used for generic cases.
Differential revision: https://reviews.llvm.org/D64714
llvm-svn: 366203
It does not make sence to stop dumping the object if the broken
dynamic section was found. In this patch I changed the behavior from
"report an error" to "report a warning". This matches GNU.
Differential revision: https://reviews.llvm.org/D64472
llvm-svn: 365762
The errors coming from ELF.h are usually not very
useful because they are uninformative. This patch is a
first step to improve the situation.
I tested this patch with a run of check-llvm and found
that few messages are untested. In this patch, I did not
add more tests but marked all such cases with a "TODO" comment.
For all tested messages I extended the error text to
provide more details (see test cases changed).
Differential revision: https://reviews.llvm.org/D64014
llvm-svn: 365183
Object/corrupt.test has the same purpose as Object/invalid.test:
it tests the behavior on invalid inputs.
In this patch I converted it to YAML, merged into invalid.test,
added comments and removed a few precompiled binaries.
Differential revision: https://reviews.llvm.org/D63927
llvm-svn: 364916
Object/invalid.test is a test case that is used to check the behavior of tools
when broken inputs are used.
The most often tool tested there is llvm-readobj. I think we might want to move
such tests to test\tools\llvm-readobj. For now this patch converts
many sub-tests to use YAML and removes 12 binaries from the inputs.
Differential revision: https://reviews.llvm.org/D63762
llvm-svn: 364522
It is now possible after D61937 was landed and was discussed
in it's review comments. It is not consistent with GNU, which
does not output .dynamic section content in this case for
no visible reason.
Differential revision: https://reviews.llvm.org/D62179
llvm-svn: 361943
-t is --symbols in llvm-readobj but --section-details (unimplemented) in readelf.
The confusing option should not be used since we aim for improving
compatibility.
Keep just one llvm-readobj -t use case in test/tools/llvm-readobj/symbols.test
llvm-svn: 359661
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.
In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.
While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).
llvm-svn: 359649
Summary:
getRelocatedValue may compute incorrect value for SHT_RELA-typed relocation entries.
// DWARFDataExtractor.cpp
uint64_t DWARFDataExtractor::getRelocatedValue(uint32_t Size, uint32_t *Off,
...
// This formula is correct for REL, but may be incorrect for RELA if the value
// stored in the location (getUnsigned(Off, Size)) is not zero.
return getUnsigned(Off, Size) + Rel->Value;
In this patch, we
* refactor these visit* functions to include a new parameter `uint64_t A`.
Since these visit* functions are no longer used as visitors, rename them to resolve*.
+ REL: A is used as the addend. A is the value stored in the location where the
relocation applies: getUnsigned(Off, Size)
+ RELA: The addend encoded in RelocationRef is used, e.g. getELFAddend(R)
* and add another set of supports* functions to check if a given relocation type is handled.
DWARFObjInMemory uses them to fail early.
Reviewers: echristo, dblaikie
Reviewed By: echristo
Subscribers: mgorny, aprantl, aheejin, fedor.sergeev, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57939
llvm-svn: 356729
The ELF specification says that all ELF data structures are aligned to
their natural alignments both in memory and file. That means when we
access mmap'ed ELF files, we could assume that all data structures are
aligned properly.
However, in reality, we assume that the data structures are aligned only
to two bytes because .a files only guarantee that their member files are
aligned to two bytes in archive files. So the data access is already
unaligned.
This patch relaxes the alignment requirement even more, so that we
accept unaligned access to all ELF data structures.
This patch in particular makes lld bug-compatible with icc. Intel C
compiler doesn't seem to care about data alignment and generates unaligned
relocation sections (https://bugs.llvm.org/show_bug.cgi?id=35854).
I also saw another instance of compatibility issues with our internal tool
which creates unaligned section headers.
Because GNU linkers are not picky about alignment, looks like it is
not uncommon that ELF-generating tools create unaligned files.
There is a performance penalty with this patch on host machines on which
unaligned access is expensive. x86 and AArch64 are fine. ARMv6 is a
problem, but I don't think using ARMv6 machines as hosts is common, so I
believe it's not a real problem.
Differential Revision: https://reviews.llvm.org/D41978
llvm-svn: 322407
The previous code was discarding the error message from
createBinary() by calling errorToErrorCode().
This meant that such error were always reported unhelpfully
as "Invalid data was encountered while parsing the file".
Other tools such as llvm-objdump already produce a more
the error message in this case.
Differential Revision: https://reviews.llvm.org/D32985
llvm-svn: 302664
This has two advantages:
1) We slowly move away from ErrorOr to the new handling interface,
in the hope of having an uniform error handling in LLVM, eventually.
2) We're starting to have *meaningful* error messages for invalid
object ELF files, rather than a generic "parse error". At some point
we should include also the offset to improve the quality of the
diagnostic.
llvm-svn: 287081
with fix: edited invalid-section-index2.elf input to pass the new check and
fail on the same place it was intended to fail.
Original commit message:
Elf.h already has code checking that section table does not go past end of file.
Problem is that this check may not work on values greater than UINT64_MAX / Header->e_shentsize
because of calculation overflow.
Parch fixes the issue.
Differential revision: https://reviews.llvm.org/D25432
llvm-svn: 285586
Elf.h already has code checking that section table does not go past end of file.
Problem is that this check may not work on values greater than UINT64_MAX / Header->e_shentsize
because of calculation overflow.
Parch fixes the issue.
Differential revision: https://reviews.llvm.org/D25432
llvm-svn: 285285
Revealed using "id_000038,sig_11,src_000015,op_havoc,rep_16" from PR30540,
when sh_size was 0, crash happened.
Differential revision: https://reviews.llvm.org/D25091
llvm-svn: 285282
Patch checks that section pointer is aligned properly.
This should be done before getStringTable() call.
Differential revision: https://reviews.llvm.org/D25462
llvm-svn: 284387
With fix: hex edited the precompiled inputs from another testcases to pass new checks.
Original commit message:
[Object/ELF] - Check that e_shnum is null when e_shoff is.
Spec says (http://www.sco.com/developers/gabi/1998-04-29/ch4.eheader.html) :
e_shnum
This member holds the number of entries in the section header table. Thus the product of e_shentsize and e_shnum gives the section header table's size in bytes. If a file has no section header table, e_shnum holds the value zero.
Revealed using "id_000037,sig_11,src_000015,op_havoc,rep_8" from PR30540
That was the reason of crash in lld on incorrect input file.
Binary reduced using afl-min.
Differential revision: https://reviews.llvm.org/D25090
llvm-svn: 284374
Fangrui Song