diff options
Diffstat (limited to 'sysdeps/generic')
| -rw-r--r-- | sysdeps/generic/dl-sysdep.c | 25 | ||||
| -rw-r--r-- | sysdeps/generic/sbrk.c | 18 |
2 files changed, 23 insertions, 20 deletions
diff --git a/sysdeps/generic/dl-sysdep.c b/sysdeps/generic/dl-sysdep.c index 36349a5658..0dfb499d52 100644 --- a/sysdeps/generic/dl-sysdep.c +++ b/sysdeps/generic/dl-sysdep.c @@ -31,21 +31,26 @@ Cambridge, MA 02139, USA. */ extern int _dl_argc; extern char **_dl_argv; extern char **_environ; +extern void _end; extern void _start (void); int __libc_enable_secure; +int __libc_multiple_libcs; /* Defining this here avoids the inclusion + of init-first. */ ElfW(Addr) _dl_sysdep_start (void **start_argptr, void (*dl_main) (const ElfW(Phdr) *phdr, ElfW(Word) phnum, ElfW(Addr) *user_entry)) { - const ElfW(Phdr) *phdr; - ElfW(Word) phnum; + const ElfW(Phdr) *phdr = NULL; + ElfW(Word) phnum = 0; ElfW(Addr) user_entry; ElfW(auxv_t) *av; - uid_t uid, euid; - gid_t gid, egid; + uid_t uid = 0; + uid_t euid = 0; + gid_t gid = 0; + gid_t egid = 0; unsigned int seen; user_entry = (ElfW(Addr)) &_start; @@ -103,6 +108,18 @@ _dl_sysdep_start (void **start_argptr, DL_SYSDEP_INIT; #endif + if (__sbrk (0) == &_end) + { + /* The dynamic linker was run as a program, and so the initial break + starts just after our bss, at &_end. The malloc in dl-minimal.c + will consume the rest of this page, so tell the kernel to move the + break up that far. When the user program examines its break, it + will see this new value and not clobber our data. */ + size_t pg = __getpagesize (); + + __sbrk (pg - ((&_end - (void *) 0) & (pg - 1))); + } + (*dl_main) (phdr, phnum, &user_entry); return user_entry; } diff --git a/sysdeps/generic/sbrk.c b/sysdeps/generic/sbrk.c index d3ea705294..afed5902dc 100644 --- a/sysdeps/generic/sbrk.c +++ b/sysdeps/generic/sbrk.c @@ -38,22 +38,8 @@ __sbrk (ptrdiff_t increment) instances of __brk and __sbrk can share the heap, returning interleaved pieces of it. */ if (__curbrk == NULL || __libc_multiple_libcs) - { - extern void _end; - - if (__brk (0) < 0) /* Initialize the break. */ - return (void *) -1; - - /* Align break address to page boundary if not happened before. */ - if (!__libc_multiple_libcs && __curbrk == &_end) - { - size_t pg = __getpagesize (); - ptrdiff_t rest = pg - ((&_end - (void *) 0) & (pg - 1)); - - if (__brk (__curbrk + rest) < 0) - return (void *) -1; - } - } + if (__brk (0) < 0) /* Initialize the break. */ + return (void *) -1; if (increment == 0) return __curbrk; |