According to the ELF specification, the file size of a PT_LOAD
memory segment might be less than its memory size. In that case,
the remaining bytes must be filled with zeros. The ELF DFI implementation
didn't handle this case correctly. Such ELF core files might be produced
by the makedumpfile tool.
From elf.5 man page:
------------------------------------------------------
PT_LOAD
The array element specifies a loadable segment,
described by p_filesz and p_memsz. The bytes
from the file are mapped to the beginning of the
memory segment. If the segment's memory size
p_memsz is larger than the file size p_filesz,
the "extra" bytes are defined to hold the value
0 and to follow the segment's initialized area.
The file size may not be larger than the memory
size. Loadable segment entries in the program
header table appear in ascending order, sorted
on the p_vaddr member.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Before attempting to read ELF program headers, the file must be positioned
at the offset of the first program header as specified in the ELF header.
Furthermore, read all ELF program headers with one call to zg_read(). This
has the advantage of not having to restore the file offset every time
after it is changed in pt_notes_add() and other functions which need to
read the same file as well.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
The DFI memory chunk manager cannot handle PT_LOAD segments of size 0.
This can lead to a NULL pointer access in mem_chunk_find() in case
zgetdump is given an invalid VMCORE ELF file as input which contains
only zero-sized ELF PT_LOAD segments. Instead of crashing, show an error
message and terminate gracefully.
The TELA test dump_with_zero_sized_segments.sh can reproduce this bug.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Verify the given ELF header before adding any memory chunks otherwise
a memory chunk might be added even if the given ELF header is invalid.
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Adjust ELF formatted dump processing by zgetdump tool in order to handle
so-called zero loads using zero memory chunks introduced with s390
extended dump format.
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
This commit is based on the s390-tools-1.39.0 version.
Changes on top of s390-tools-1.39.0:
- Add MIT license to all source files
- Add LICENSE file
- Transform REAMDE to README.md (markdown)
- Add AUTHORS.md file
- Add CONTRIBUTING.md file
- Move changelog from README to CHANGELOG.md file
Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Alexander Egorenkov