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| author | Ryan Arnold <ryanarn@etna.rchland.ibm.com> | 2010-06-11 15:11:10 -0500 |
|---|---|---|
| committer | Ryan Arnold <ryanarn@etna.rchland.ibm.com> | 2010-06-29 17:09:36 -0500 |
| commit | 052b16c76579af4519983e47c8d1d1f05d9a81a8 (patch) | |
| tree | 19144db266688a1b5b502e55d4c40dca9239f987 | |
| parent | 5af95888b07369ead5620d266bde16d79f8e2f95 (diff) | |
| download | glibc-052b16c76579af4519983e47c8d1d1f05d9a81a8.zip glibc-052b16c76579af4519983e47c8d1d1f05d9a81a8.tar.gz glibc-052b16c76579af4519983e47c8d1d1f05d9a81a8.tar.bz2 | |
Experimental patch to default PPC64 to no-execstack support. This will need
to be abstracted to remove the guards from common files and put the stack
initialization into a header file that can be overridden.
2010-06-11 Ryan S. Arnold <rsa@us.ibm.com>
* elf/dl-load.c (_dl_map_object_from_fd): Set default stack_flags to
no-exec for ARCH_PPC64.
* elf/dl-support.c [_dl_stack_flags]: Set default stack_flags to
no-exec for ARCH_PPC64.
* elf/rtld.c (_dl_starting_up): Set default stack_flags to no-exec for
ARCH_PPC64.
| -rw-r--r-- | ChangeLog | 9 | ||||
| -rw-r--r-- | elf/dl-load.c | 5 | ||||
| -rw-r--r-- | elf/dl-support.c | 7 | ||||
| -rw-r--r-- | elf/rtld.c | 5 |
4 files changed, 26 insertions, 0 deletions
@@ -1,3 +1,12 @@ +2010-06-11 Ryan S. Arnold <rsa@us.ibm.com> + + * elf/dl-load.c (_dl_map_object_from_fd): Set default stack_flags to + no-exec for ARCH_PPC64. + * elf/dl-support.c [_dl_stack_flags]: Set default stack_flags to + no-exec for ARCH_PPC64. + * elf/rtld.c (_dl_starting_up): Set default stack_flags to no-exec for + ARCH_PPC64. + 2009-09-04 H.J. Lu <hongjiu.lu@intel.com> * configure.in: Support binutils 2.20. diff --git a/elf/dl-load.c b/elf/dl-load.c index 94531b2..ca7115e 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1000,8 +1000,13 @@ _dl_map_object_from_fd (const char *name, int fd, struct filebuf *fbp, } } +#if (defined (_ARCH_PPC64) || defined (__powerpc64__)) + /* Default to no-exec stack on PPC64. */ + uint_fast16_t stack_flags = PF_R|PF_W; +#else /* Presumed absent PT_GNU_STACK. */ uint_fast16_t stack_flags = PF_R|PF_W|PF_X; +#endif { /* Scan the program header table, collecting its load commands. */ diff --git a/elf/dl-support.c b/elf/dl-support.c index 2c11ac6..582d3ed 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -122,8 +122,15 @@ ElfW(Phdr) *_dl_phdr; size_t _dl_phnum; uint64_t _dl_hwcap __attribute__ ((nocommon)); + +#if (defined (_ARCH_PPC64) || defined (__powerpc64__)) +/* Default to no-exec stack on PPC64. */ +/* Prevailing state of the stack, PF_X indicating it's executable. */ +ElfW(Word) _dl_stack_flags = PF_R|PF_W; +#else /* Prevailing state of the stack, PF_X indicating it's executable. */ ElfW(Word) _dl_stack_flags = PF_R|PF_W|PF_X; +#endif /* If loading a shared object requires that we make the stack executable when it was not, we do it by calling this function. @@ -123,7 +123,12 @@ INTVARDEF(_dl_starting_up) struct rtld_global _rtld_global = { /* Default presumption without further information is executable stack. */ +#if (defined (_ARCH_PPC64) || defined (__powerpc64__)) + /* Default to no-exec stack on PPC64. */ + ._dl_stack_flags = PF_R|PF_W, +#else ._dl_stack_flags = PF_R|PF_W|PF_X, +#endif #ifdef _LIBC_REENTRANT ._dl_load_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER #endif |