Commit Graph

11 Commits

Author SHA1 Message Date
Georgii Rymar 9c89dcf807 [yaml2obj, obj2yaml] - Implement section header table as a special Chunk.
This was discussed in D93678 thread.
Currently we have one special chunk - Fill.

This patch re implements the "SectionHeaderTable" key to become a special chunk too.
With that we are able to place the section header table at any location,
just like we place sections.

Differential revision: https://reviews.llvm.org/D95140
2021-01-25 13:08:08 +03:00
Georgii Rymar a7a447be0f [yaml2obj] - ProgramHeaders: introduce FirstSec/LastSec instead of Sections list.
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.

To put them into segment we can do (1*):

```
Sections:
 - Section: foo1
 - Section: foo4
```

or we can use (2*):

```
Sections:
 - Section: foo1
 - Section: foo3
 - Section: foo4
```

or (3*) :

```
Sections:
 - Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
 - Section: (index 2)
 - Section: foo3
 - Section: foo4
```

It looks really confusing that we don't have to list all of sections.

At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).

This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.

Differential revision: https://reviews.llvm.org/D90458
2020-11-09 13:00:50 +03:00
Georgii Rymar fcf6287916 [yaml2obj] - Improve handling of SectionHeaderTable::NoHeaders flag.
When `NoHeaders` is set, we still have following issues:
1) We emit the `.shstrtab` implicit section of size 1 (empty string table).
2) We still align the start of the section header table, what affects the output size.
3) We still write section header table bytes.

This patch fixes all of these issues.

Differential revision: https://reviews.llvm.org/D90295
2020-10-29 12:16:52 +03:00
Georgii Rymar 275bed899e [llvm-readelf/obj] - Change the return type of the `createDRI(...)` to `Expected<>`
This allows to get rid of "Invalid data was encountered while parsing the file"
error reported in cases when sh_size/sh_offset of sections are broken.

Differential revision: https://reviews.llvm.org/D86451
2020-08-25 12:11:26 +03:00
Georgii Rymar aa456a6df4 [llvm-readobj/elf] - Refine the code for broken PT_DYNAMIC segment diagnostic.
The code that reports "PT_DYNAMIC segment offset + size exceeds the size of the file"
has an issue: it is possible to bypass the validation by overflowing the size + offset result.

Differential revision: https://reviews.llvm.org/D85519
2020-08-21 15:05:46 +03:00
Georgii Rymar 61152a71a1 Revert "[llvm-readobj/elf] - Refine the code for broken PT_DYNAMIC segment diagnostic."
This reverts commit 455d5a8a06.

It broke UBSan:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-ubsan/builds/21386/steps/check-llvm%20ubsan/logs/stdio

/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/test/tools/llvm-readobj/ELF/malformed-pt-dynamic.test:62:10: error: WARN3: expected string not found in input
# WARN3: error: '[[FILE]]': Invalid data was encountered while parsing the file
         ^
<stdin>:2:1: note: scanning from here
/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/tools/llvm-readobj/ELFDumper.cpp:1956:46: runtime error: addition of unsigned offset to 0x0000020c5b30 overflowed to 0x0000020c5b2f
^
<stdin>:2:1: note: with "FILE" equal to "/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm_build_ubsan/test/tools/llvm-readobj/ELF/Output/malformed-pt-dynamic\\.test\\.tmp3"
/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/tools/llvm-readobj/ELFDumper.cpp:1956:46: runtime error: addition of unsigned offset to 0x0000020c5b30 overflowed to 0x0000020c5b2f
^
<stdin>:2:117: note: possible intended match here
/b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/tools/llvm-readobj/ELFDumper.cpp:1956:46: runtime error: addition of unsigned offset to 0x0000020c5b30 overflowed to 0x0000020c5b2f
                                                                                                                    ^
Input file: <stdin>
Check file: /b/sanitizer-x86_64-linux-bootstrap-ubsan/build/llvm-project/llvm/test/tools/llvm-readobj/ELF/malformed-pt-dynamic.test
2020-08-20 14:04:30 +03:00
Georgii Rymar 455d5a8a06 [llvm-readobj/elf] - Refine the code for broken PT_DYNAMIC segment diagnostic.
The code that reports "PT_DYNAMIC segment offset + size exceeds the size of the file"
has an issue: it is possible to bypass the validation by overflowing the size + offset result.

Differential revision: https://reviews.llvm.org/D85519
2020-08-20 12:28:34 +03:00
Georgii Rymar a6436b0b3a [yaml2obj] - Make the 'Machine' key optional.
Currently we have to set 'Machine' to something in our
YAML descriptions. Usually we use 'EM_X86_64' for 64-bit targets
and 'EM_386' for 32-bit targets. At the same time, in fact, in most
cases our tests do not need a machine type and we can use
'EM_NONE'.

This is cleaner, because avoids the need of using a particular machine.

In this patch I've made the 'Machine' key optional (the default value,
when it is not specified is `EM_NONE`) and removed it (where possible)
from yaml2obj, obj2yaml and llvm-readobj tests.

There are few tests left where I decided not to remove it, because
I didn't want to touch CHECK lines or doing anything more complex
than a removing a "Machine: *" line and formatting lines around.

Differential revision: https://reviews.llvm.org/D86202
2020-08-20 11:40:51 +03:00
Georgii Rymar 6786b3e307 [llvm-readobj/elf] - Refine the malformed-pt-dynamic.test.
This is splitted out from D85519, but significantly reworked.

Changes:
1) This test was changed to stop using python.
2) Use NoHeaders: true instead of `llvm-objcopy --strip-sections`.
3) Test llvm-readelf too (not just llvm-readobj).
4) Simplify the YAML used a bit (e.g. remove PT_LOAD).
5) Test 2 different cases: objects with section header table and without.

Differential revision: https://reviews.llvm.org/D86073
2020-08-18 11:51:03 +03:00
Georgii Rymar 6567f82216 [llvm-readobj/elf] - Refine the warning about the broken PT_DYNAMIC segment.
Splitted out from D85519.

Currently we report "PT_DYNAMIC segment offset + size exceeds the size of the file",
this changes it to
"PT_DYNAMIC segment offset (0x1234) + file size (0x5678) exceeds the size of the file (0x68ab)"

Differential revision: https://reviews.llvm.org/D85654
2020-08-17 14:57:19 +03:00
Georgii Rymar dbf520f617 [llvm-readobj][test] - Move platform specific test cases and their inputs to separate folders.
This creates the next subfolders in the test directory:
"COFF", "ELF", "MachO", "wasm".

I've also removed platform specific prefixes, like "coff-*".
One unused binary was removed as well: `Inputs/relocs.obj.elf-mips`

Differential revision: https://reviews.llvm.org/D71203
2019-12-10 11:36:23 +03:00