[gentoo-commits] proj/pax-utils:master commit in: /

[Mike Frysinger]

commit:     82fc8ce64f61445c52e5c9a4d5ac294b6af7c92d
Author:     Mike Frysinger <vapier <AT> gentoo <DOT> org>
AuthorDate: Tue Jan 24 02:13:03 2017 +0000
Commit:     Mike Frysinger <vapier <AT> gentoo <DOT> org>
CommitDate: Tue Jan 24 02:13:03 2017 +0000
URL:        https://gitweb.gentoo.org/proj/pax-utils.git/commit/?id=82fc8ce6

scanelf: fix offset checking when looking up symbols via hash

A number of refactors hid bugs here in that the first offset value
here would be left over from earlier code.  Localize the code a bit
to try and keep that from happening again.

We also reload phdr since this loop expects to walk the whole table.

 scanelf.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/scanelf.c b/scanelf.c
index 2729d0f..52c436a 100644
--- a/scanelf.c
+++ b/scanelf.c
@@ -261,7 +261,7 @@ static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **str)
 	Elf ## B ## _Phdr *phdr; \
 	Elf ## B ## _Addr vsym, vstr, vhash, vgnu_hash; \
 	Elf ## B ## _Dyn *dyn; \
-	Elf ## B ## _Off offset; \
+	Elf ## B ## _Off doffset; \
 	\
 	/* lookup symbols used at runtime with DT_SYMTAB / DT_STRTAB */ \
 	vsym = vstr = vhash = vgnu_hash = 0; \
@@ -272,9 +272,9 @@ static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **str)
 	phdr = scanelf_file_get_pt_dynamic(elf); \
 	if (phdr == NULL) \
 		break; \
-	offset = EGET(phdr->p_offset); \
+	doffset = EGET(phdr->p_offset); \
 	\
-	dyn = DYN ## B (elf->vdata + offset); \
+	dyn = DYN ## B (elf->vdata + doffset); \
 	while (EGET(dyn->d_tag) != DT_NULL) { \
 		switch (EGET(dyn->d_tag)) { \
 		case DT_SYMTAB:   vsym = EGET(dyn->d_un.d_val); break; \
@@ -290,15 +290,16 @@ static void scanelf_file_get_symtabs(elfobj *elf, void **sym, void **str)
 		return; \
 	\
 	/* calc offset into the ELF by finding the load addr of the syms */ \
+	phdr = PHDR ## B (elf->phdr); \
 	for (i = 0; i < EGET(ehdr->e_phnum); i++) { \
 		Elf ## B ## _Addr vaddr = EGET(phdr[i].p_vaddr); \
 		Elf ## B ## _Addr filesz = EGET(phdr[i].p_filesz); \
+		Elf ## B ## _Off offset = EGET(phdr[i].p_offset); \
 		Elf ## B ## _Off hash_offset = offset + (vhash - vaddr); \
 		\
 		if (EGET(phdr[i].p_type) != PT_LOAD) \
 			continue; \
 		\
-		offset = EGET(phdr[i].p_offset); \
 		if (offset >= (uint64_t)elf->len) \
 			goto corrupt_hash; \
 		if (filesz >= (uint64_t)elf->len) \