diff options
| author | Mark Wielaard <mark@klomp.org> | 2021-12-19 23:58:32 +0100 |
|---|---|---|
| committer | Mark Wielaard <mark@klomp.org> | 2021-12-19 23:58:32 +0100 |
| commit | 34ef8b44ed5998b025bd77fde4c71d7d8e585cf0 (patch) | |
| tree | a9297a1db37dd827ba156c73b67bfae75d7482e3 /libdwfl | |
| parent | d844d1575522b5ad9ada0aa3c26105230a1c1884 (diff) | |
| download | elfutils-34ef8b44ed5998b025bd77fde4c71d7d8e585cf0.tar.gz | |
libdwfl: Handle unaligned Ehdr in dwfl_segment_report_module
The xlate functions only handle correctly aligned buffers. But they do
handle src == dest. So if the source buffer isn't aligned correctly
just copy it first into the destination (which is already correctly
aligned).
Signed-off-by: Mark Wielaard <mark@klomp.org>
Diffstat (limited to 'libdwfl')
| -rw-r--r-- | libdwfl/ChangeLog | 5 | ||||
| -rw-r--r-- | libdwfl/dwfl_segment_report_module.c | 14 |
2 files changed, 19 insertions, 0 deletions
diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog index 18ffc347..6c7e0c4a 100644 --- a/libdwfl/ChangeLog +++ b/libdwfl/ChangeLog @@ -1,5 +1,10 @@ 2021-12-19 Mark Wielaard <mark@klomp.org> + * dwfl_segment_report_module.c (dwfl_segment_report_module): Copy + buffer and set xlatefrom.d_buf to ehdr when buffer is not aligned. + +2021-12-19 Mark Wielaard <mark@klomp.org> + * dwfl_segment_report_module.c (dwfl_segment_report_module): Check notes filesz. Rewrite reading of GElf_Nhdr. diff --git a/libdwfl/dwfl_segment_report_module.c b/libdwfl/dwfl_segment_report_module.c index a6d6be85..7f756392 100644 --- a/libdwfl/dwfl_segment_report_module.c +++ b/libdwfl/dwfl_segment_report_module.c @@ -367,6 +367,20 @@ dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name, e_ident = ((const unsigned char *) buffer); ei_class = e_ident[EI_CLASS]; ei_data = e_ident[EI_DATA]; + /* buffer may be unaligned, in which case xlatetom would not work. + xlatetom does work when the in and out d_buf are equal (but not + for any other overlap). */ + size_t ehdr_align = (ei_class == ELFCLASS32 + ? __alignof__ (Elf32_Ehdr) + : __alignof__ (Elf64_Ehdr)); + if (((uintptr_t) buffer & (ehdr_align - 1)) != 0) + { + memcpy (&ehdr, buffer, + (ei_class == ELFCLASS32 + ? sizeof (Elf32_Ehdr) + : sizeof (Elf64_Ehdr))); + xlatefrom.d_buf = &ehdr; + } switch (ei_class) { case ELFCLASS32: |