diff options
| author | Mark Wielaard <mjw@redhat.com> | 2013-11-08 19:28:16 +0100 |
|---|---|---|
| committer | Mark Wielaard <mjw@redhat.com> | 2013-11-11 15:07:44 +0100 |
| commit | 3ba50403179131d6153923af71d00a909b62a147 (patch) | |
| tree | f77cf7108b35ceb22468df12bdfdc5d1d50b9ba6 | |
| parent | 03d76f4aec5e750b81198c7a24571e119e754b40 (diff) | |
| download | elfutils-3ba50403179131d6153923af71d00a909b62a147.tar.gz | |
libelf: Only memcpy ehdr back when not already directly mmapped.
When the elf file is mmapped ehdr can still point to ehdr_mem if the
address is unaligned. In such cases we do need to memcpy the ehdr back
to the file. We shouldn't when ehdr already comes directly from the mmapped
file, because that would cause an memcpy call with overlapping addresses
(ehdr being copied directly over itself).
Signed-off-by: Mark Wielaard <mjw@redhat.com>
| -rw-r--r-- | libelf/ChangeLog | 5 | ||||
| -rw-r--r-- | libelf/elf32_updatefile.c | 2 |
2 files changed, 6 insertions, 1 deletions
diff --git a/libelf/ChangeLog b/libelf/ChangeLog index a996ccf6..148c9453 100644 --- a/libelf/ChangeLog +++ b/libelf/ChangeLog @@ -1,3 +1,8 @@ +2013-11-08 Mark Wielaard <mjw@redhat.com> + + * elf32_updatefile.c (elfXX_updatemmap): Only memcpy ehdr when not + already directly mmapped. + 2013-11-05 Mark Wielaard <mjw@redhat.com> * elf32_updatefile.c (elfXX_updatefile): Copy all section headers diff --git a/libelf/elf32_updatefile.c b/libelf/elf32_updatefile.c index c4af9c02..b39e2841 100644 --- a/libelf/elf32_updatefile.c +++ b/libelf/elf32_updatefile.c @@ -133,7 +133,7 @@ __elfw2(LIBELFBITS,updatemmap) (Elf *elf, int change_bo, size_t shnum) (*fctp) ((char *) elf->map_address + elf->start_offset, ehdr, sizeof (ElfW2(LIBELFBITS,Ehdr)), 1); } - else + else if (elf->map_address + elf->start_offset != ehdr) memcpy (elf->map_address + elf->start_offset, ehdr, sizeof (ElfW2(LIBELFBITS,Ehdr))); |