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Diffstat (limited to 'elf/dl-load.c')
-rw-r--r--elf/dl-load.c94
1 files changed, 86 insertions, 8 deletions
diff --git a/elf/dl-load.c b/elf/dl-load.c
index 06f2ba7..e39980f 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -853,6 +853,77 @@ lose (int code, int fd, const char *name, char *realname, struct link_map *l,
}
+/* Process PT_GNU_PROPERTY program header PH in module L after
+ PT_LOAD segments are mapped. Only one NT_GNU_PROPERTY_TYPE_0
+ note is handled which contains processor specific properties. */
+
+void
+_dl_process_pt_gnu_property (struct link_map *l, const ElfW(Phdr) *ph)
+{
+ const ElfW(Nhdr) *note = (const void *) (ph->p_vaddr + l->l_addr);
+ const ElfW(Addr) size = ph->p_memsz;
+ const ElfW(Addr) align = ph->p_align;
+
+ /* The NT_GNU_PROPERTY_TYPE_0 note must be aligned to 4 bytes in
+ 32-bit objects and to 8 bytes in 64-bit objects. Skip notes
+ with incorrect alignment. */
+ if (align != (__ELF_NATIVE_CLASS / 8))
+ return;
+
+ const ElfW(Addr) start = (ElfW(Addr)) note;
+ unsigned int last_type = 0;
+
+ while ((ElfW(Addr)) (note + 1) - start < size)
+ {
+ /* Find the NT_GNU_PROPERTY_TYPE_0 note. */
+ if (note->n_namesz == 4
+ && note->n_type == NT_GNU_PROPERTY_TYPE_0
+ && memcmp (note + 1, "GNU", 4) == 0)
+ {
+ /* Check for invalid property. */
+ if (note->n_descsz < 8
+ || (note->n_descsz % sizeof (ElfW(Addr))) != 0)
+ return;
+
+ /* Start and end of property array. */
+ unsigned char *ptr = (unsigned char *) (note + 1) + 4;
+ unsigned char *ptr_end = ptr + note->n_descsz;
+
+ do
+ {
+ unsigned int type = *(unsigned int *) ptr;
+ unsigned int datasz = *(unsigned int *) (ptr + 4);
+
+ /* Property type must be in ascending order. */
+ if (type < last_type)
+ return;
+
+ ptr += 8;
+ if ((ptr + datasz) > ptr_end)
+ return;
+
+ last_type = type;
+
+ /* Target specific property processing. */
+ if (_dl_process_gnu_property (l, type, datasz, ptr) == 0)
+ return;
+
+ /* Check the next property item. */
+ ptr += ALIGN_UP (datasz, sizeof (ElfW(Addr)));
+ }
+ while ((ptr_end - ptr) >= 8);
+
+ /* Only handle one NT_GNU_PROPERTY_TYPE_0. */
+ return;
+ }
+
+ note = ((const void *) note
+ + ELF_NOTE_NEXT_OFFSET (note->n_namesz, note->n_descsz,
+ align));
+ }
+}
+
+
/* Map in the shared object NAME, actually located in REALNAME, and already
opened on FD. */
@@ -1145,14 +1216,6 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
l->l_relro_addr = ph->p_vaddr;
l->l_relro_size = ph->p_memsz;
break;
-
- case PT_NOTE:
- if (_dl_process_pt_note (l, ph, fd, fbp))
- {
- errstring = N_("cannot process note segment");
- goto call_lose;
- }
- break;
}
if (__glibc_unlikely (nloadcmds == 0))
@@ -1188,6 +1251,21 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
maplength, has_holes, loader);
if (__glibc_unlikely (errstring != NULL))
goto call_lose;
+
+ /* Process program headers again after load segments are mapped in
+ case processing requires accessing those segments. Scan program
+ headers backward so that PT_NOTE can be skipped if PT_GNU_PROPERTY
+ exits. */
+ for (ph = &phdr[l->l_phnum]; ph != phdr; --ph)
+ switch (ph[-1].p_type)
+ {
+ case PT_NOTE:
+ _dl_process_pt_note (l, &ph[-1]);
+ break;
+ case PT_GNU_PROPERTY:
+ _dl_process_pt_gnu_property (l, &ph[-1]);
+ break;
+ }
}
if (l->l_ld == 0)