rtld: parse FreeBSD Feature Control note on the object load.

Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
This commit is contained in:
Konstantin Belousov 2018-11-23 22:37:35 +00:00
parent 6c81fe160c
commit e8927aa6c6
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=340858
2 changed files with 9 additions and 0 deletions

View File

@ -1477,6 +1477,7 @@ digest_notes(Obj_Entry *obj, Elf_Addr note_start, Elf_Addr note_end)
note->n_descsz != sizeof(int32_t)) note->n_descsz != sizeof(int32_t))
continue; continue;
if (note->n_type != NT_FREEBSD_ABI_TAG && if (note->n_type != NT_FREEBSD_ABI_TAG &&
note->n_type != NT_FREEBSD_FEATURE_CTL &&
note->n_type != NT_FREEBSD_NOINIT_TAG) note->n_type != NT_FREEBSD_NOINIT_TAG)
continue; continue;
note_name = (const char *)(note + 1); note_name = (const char *)(note + 1);
@ -1491,6 +1492,13 @@ digest_notes(Obj_Entry *obj, Elf_Addr note_start, Elf_Addr note_end)
obj->osrel = *(const int32_t *)(p); obj->osrel = *(const int32_t *)(p);
dbg("note osrel %d", obj->osrel); dbg("note osrel %d", obj->osrel);
break; break;
case NT_FREEBSD_FEATURE_CTL:
/* FreeBSD ABI feature control note */
p = (uintptr_t)(note + 1);
p += roundup2(note->n_namesz, sizeof(Elf32_Addr));
obj->fctl0 = *(const uint32_t *)(p);
dbg("note fctl0 %#x", obj->fctl0);
break;
case NT_FREEBSD_NOINIT_TAG: case NT_FREEBSD_NOINIT_TAG:
/* FreeBSD 'crt does not call init' note */ /* FreeBSD 'crt does not call init' note */
obj->crt_no_init = true; obj->crt_no_init = true;

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@ -235,6 +235,7 @@ typedef struct Struct_Obj_Entry {
int fini_array_num; /* Number of entries in fini_array */ int fini_array_num; /* Number of entries in fini_array */
int32_t osrel; /* OSREL note value */ int32_t osrel; /* OSREL note value */
uint32_t fctl0; /* FEATURE_CONTROL note desc[0] value */
bool mainprog : 1; /* True if this is the main program */ bool mainprog : 1; /* True if this is the main program */
bool rtld : 1; /* True if this is the dynamic linker */ bool rtld : 1; /* True if this is the dynamic linker */