diff options
| author | Carmelo Amoroso <carmelo.amoroso@st.com> | 2007-11-16 14:32:35 +0000 |
|---|---|---|
| committer | Carmelo Amoroso <carmelo.amoroso@st.com> | 2007-11-16 14:32:35 +0000 |
| commit | a6eef2edb3dada9ee1a0765dd7901d0a988f30ce (patch) | |
| tree | 64010526390195481e6443108fc862064b651915 | |
| parent | e130b681c43ee2215512ffcf6cadcbc4487e96e6 (diff) | |
If uClibc's ld.so encounters text relocations in a shared library - one
containing an object built without -fpic/-fPIC - then:
* If __FORCE_SHAREABLE_TEXT_SEGMENTS__, then it gives an error "Can't
modify %s's text section. Use GCC option -fPIC for shared objects,
please.\n" and exits.
* Otherwise, it makes the library's pages writable and relocates it.
If it encounters text relocations in a position-independent executable -
one containing an object built without -fpie/-fPIE/-fpic/-fPIC - then:
* If __FORCE_SHAREABLE_TEXT_SEGMENTS__, it does nothing about making the
pages writable, leading to a crash.
* Otherwise, the loop to make the pages writable uses the same variable
ppnt as used in an outer loop, messing up that outer loop and also causing
a crash.
This patch fixes both cases, by giving an error if
__FORCE_SHAREABLE_TEXT_SEGMENTS__ and saving and restoring ppnt otherwise.
Tested in both cases on ARM EABI.
Joseph S. Myers
joseph@codesourcery.com
| -rw-r--r-- | ldso/ldso/ldso.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c index e1101bd57..3a5fc14f5 100644 --- a/ldso/ldso/ldso.c +++ b/ldso/ldso/ldso.c @@ -286,6 +286,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, _dl_debug_early("calling mprotect on the application program\n"); /* Now cover the application program. */ if (app_tpnt->dynamic_info[DT_TEXTREL]) { + ElfW(Phdr) *ppnt_outer = ppnt; ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val; for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) { if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W)) @@ -294,6 +295,12 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, (unsigned long) ppnt->p_filesz, PROT_READ | PROT_WRITE | PROT_EXEC); } + ppnt = ppnt_outer; + } +#else + if (app_tpnt->dynamic_info[DT_TEXTREL]) { + _dl_dprintf(_dl_debug_file, "Can't modify application's text section; use the GCC option -fPIE for position-independent executables.\n"); + _dl_exit(1); } #endif |