diff options
Diffstat (limited to 'libelf/elf32_updatefile.c')
| -rw-r--r-- | libelf/elf32_updatefile.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/libelf/elf32_updatefile.c b/libelf/elf32_updatefile.c index f2e9a288..284bacc9 100644 --- a/libelf/elf32_updatefile.c +++ b/libelf/elf32_updatefile.c @@ -1,5 +1,5 @@ /* Write changed data structures. - Copyright (C) 2000-2010, 2014, 2015, 2016 Red Hat, Inc. + Copyright (C) 2000-2010, 2014, 2015, 2016, 2018 Red Hat, Inc. This file is part of elfutils. Written by Ulrich Drepper <[email protected]>, 2000. @@ -354,7 +354,9 @@ __elfw2(LIBELFBITS,updatemmap) (Elf *elf, int change_bo, size_t shnum) user's section data with the latest one, rather than crashing. */ - if (unlikely (change_bo)) + if (unlikely (change_bo + && dl->data.d.d_size != 0 + && dl->data.d.d_type != ELF_T_BYTE)) { #if EV_NUM != 2 xfct_t fctp; @@ -364,9 +366,33 @@ __elfw2(LIBELFBITS,updatemmap) (Elf *elf, int change_bo, size_t shnum) # define fctp __elf_xfctstom[0][EV_CURRENT - 1][ELFW(ELFCLASS, LIBELFBITS) - 1][dl->data.d.d_type] #endif - /* Do the real work. */ - (*fctp) (last_position, dl->data.d.d_buf, - dl->data.d.d_size, 1); + size_t align; + align = __libelf_type_align (ELFW(ELFCLASS,LIBELFBITS), + dl->data.d.d_type); + if ((((uintptr_t) last_position) + & (uintptr_t) (align - 1)) == 0) + { + /* No need to copy, we can convert directly. */ + (*fctp) (last_position, dl->data.d.d_buf, + dl->data.d.d_size, 1); + } + else + { + /* We have to do the conversion on properly + aligned memory first. */ + size_t size = dl->data.d.d_size; + char *converted = aligned_alloc (align, size); + if (converted == NULL) + { + __libelf_seterrno (ELF_E_NOMEM); + return 1; + } + (*fctp) (converted, dl->data.d.d_buf, size, 1); + + /* And then write it to the mmapped file. */ + memcpy (last_position, converted, size); + free (converted); + } last_position += dl->data.d.d_size; } |