dwz/dwz-0.12-ignore-nobits.patch
2017-03-07 09:58:05 +00:00

139 lines
5.1 KiB
Diff

diff --git a/dwz.c b/dwz.c
index b3b779d..5ab45a2 100644
--- a/dwz.c
+++ b/dwz.c
@@ -10016,6 +10016,26 @@ error_out:
return NULL;
}
+/* Sort shdr indices after sh_offset. */
+static DSO *shdr_sort_compar_dso;
+static int
+shdr_sort_compar (const void *p1, const void *p2)
+{
+ const int *idx1 = (const int *)p1;
+ const int *idx2 = (const int *)p2;
+ if (shdr_sort_compar_dso->shdr[*idx1].sh_offset
+ < shdr_sort_compar_dso->shdr[*idx2].sh_offset)
+ return -1;
+ else if (shdr_sort_compar_dso->shdr[*idx1].sh_offset
+ > shdr_sort_compar_dso->shdr[*idx2].sh_offset)
+ return 1;
+ if (*idx1 < *idx2)
+ return -1;
+ else if (*idx1 > *idx2)
+ return 1;
+ return 0;
+}
+
/* Store new ELF into FILE. debug_sections array contains
new_data/new_size pairs where needed. */
static int
@@ -10090,7 +10110,14 @@ write_dso (DSO *dso, const char *file, struct stat *st)
if (off < min_shoff)
min_shoff = off;
for (j = 1; j < dso->ehdr.e_shnum; ++j)
- if (dso->shdr[j].sh_offset > off)
+ if (dso->shdr[j].sh_offset > off
+ /* Do not adjust SHT_NOBITS sh_offset here, the kernel
+ for example lays out those in the middle of some
+ other sections which may cause their offset to wrap
+ around zero.
+ ??? Now in theory not adjusting means we might end up
+ with those having a higher offset than any other section. */
+ && dso->shdr[j].sh_type != SHT_NOBITS)
dso->shdr[j].sh_offset += diff;
if (ehdr.e_shoff > off)
ehdr.e_shoff += diff;
@@ -10123,6 +10150,7 @@ write_dso (DSO *dso, const char *file, struct stat *st)
if (min_shoff != ~(GElf_Off) 0)
{
+ /* Any section needs sh_offset adjustment to meet sh_addralign? */
for (j = 1; j < dso->ehdr.e_shnum; ++j)
if (dso->shdr[j].sh_offset >= min_shoff
&& dso->shdr[j].sh_addralign > 1
@@ -10133,21 +10161,34 @@ write_dso (DSO *dso, const char *file, struct stat *st)
&& (ehdr.e_shoff & (ehdr.e_ident[EI_CLASS] == ELFCLASS64
? 7 : 3)) != 0))
{
+ /* Compute a section index list sorted after sh_offset. */
+ int *shdrmap = alloca (dso->ehdr.e_shnum * sizeof (int));
+ for (j = 0; j < dso->ehdr.e_shnum; ++j)
+ shdrmap[j] = j;
+ shdr_sort_compar_dso = dso;
+ qsort (shdrmap, dso->ehdr.e_shnum, sizeof (int),
+ shdr_sort_compar);
+ shdr_sort_compar_dso = NULL;
+
/* Need to fix up sh_offset/e_shoff. Punt if all the sections
>= min_shoff aren't non-ALLOC. */
GElf_Off last_shoff = 0;
int k = -1;
bool shdr_placed = false;
for (j = 1; j < dso->ehdr.e_shnum; ++j)
- if (dso->shdr[j].sh_offset < min_shoff && !last_shoff)
+ if (dso->shdr[shdrmap[j]].sh_offset < min_shoff && !last_shoff)
+ continue;
+ else if (dso->shdr[shdrmap[j]].sh_type == SHT_NOBITS)
+ /* NOBITS are just left in place where they are and their
+ sh_size does not matter. */
continue;
- else if ((dso->shdr[j].sh_flags & SHF_ALLOC) != 0)
+ else if ((dso->shdr[shdrmap[j]].sh_flags & SHF_ALLOC) != 0)
{
error (0, 0, "Allocatable section in %s after non-allocatable "
"ones", dso->filename);
return 1;
}
- else if (dso->shdr[j].sh_offset < last_shoff)
+ else if (dso->shdr[shdrmap[j]].sh_offset < last_shoff)
{
error (0, 0, "Section offsets in %s not monotonically "
"increasing", dso->filename);
@@ -10157,7 +10198,8 @@ write_dso (DSO *dso, const char *file, struct stat *st)
{
if (k == -1)
k = j;
- last_shoff = dso->shdr[j].sh_offset + dso->shdr[j].sh_size;
+ last_shoff = (dso->shdr[shdrmap[j]].sh_offset
+ + dso->shdr[shdrmap[j]].sh_size);
}
last_shoff = min_shoff;
for (j = k; j <= dso->ehdr.e_shnum; ++j)
@@ -10165,7 +10207,7 @@ write_dso (DSO *dso, const char *file, struct stat *st)
if (!shdr_placed
&& ehdr.e_shoff >= min_shoff
&& (j == dso->ehdr.e_shnum
- || ehdr.e_shoff < dso->shdr[j].sh_offset))
+ || ehdr.e_shoff < dso->shdr[shdrmap[j]].sh_offset))
{
if (ehdr.e_ident[EI_CLASS] == ELFCLASS64)
ehdr.e_shoff = (last_shoff + 7) & -8;
@@ -10176,13 +10218,18 @@ write_dso (DSO *dso, const char *file, struct stat *st)
}
if (j == dso->ehdr.e_shnum)
break;
- dso->shdr[j].sh_offset = last_shoff;
- if (dso->shdr[j].sh_addralign > 1)
- dso->shdr[j].sh_offset
- = (last_shoff + dso->shdr[j].sh_addralign - 1)
- & ~(dso->shdr[j].sh_addralign - (GElf_Off) 1);
- last_shoff = dso->shdr[j].sh_offset + dso->shdr[j].sh_size;
- if (addsec != -1 && j == addsec)
+ /* Do not touch SHT_NOBITS section offsets and more importantly
+ do not account for their size. */
+ if (dso->shdr[shdrmap[j]].sh_type == SHT_NOBITS)
+ continue;
+ dso->shdr[shdrmap[j]].sh_offset = last_shoff;
+ if (dso->shdr[shdrmap[j]].sh_addralign > 1)
+ dso->shdr[shdrmap[j]].sh_offset
+ = (last_shoff + dso->shdr[shdrmap[j]].sh_addralign - 1)
+ & ~(dso->shdr[shdrmap[j]].sh_addralign - (GElf_Off) 1);
+ last_shoff = (dso->shdr[shdrmap[j]].sh_offset
+ + dso->shdr[shdrmap[j]].sh_size);
+ if (addsec != -1 && shdrmap[j] == addsec)
last_shoff += addsize;
}
}