prelink: use ehdr.e_shstrndx as index rather than ehdr.e_shnum

[YOCTO #12791]

According to struct elf32_hd, the e_shnum is section header number, and the
index is e_shstrndx, not e_shnum.

This can fix segmention fault when handle libqb.so.0.18.2 from libqb_1.0.3.
It fails to handle libqb.so.0.18.2 and get errors:
Symbol section index outside of section numbers

Then segmentation fault, this is because the e_shnum is 34, while e_shstrndx is
27 (it would be 33 when no errors), I've checked several elf files to confirm
that the ones after e_shstrndx is NULL, so use e_shstrndx should be correct.

Fixed:
MACHINE="qemux86-64"
IMAGE_INSTALL_append = " libqb" #libqp is from meta-openembedded
$ bitbake core-image-minimal
Segmention fault

(From OE-Core rev: b7c291ee6532cba845ee6bfbbaa21076a2b2cbe5)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/meta/recipes-devtools/prelink/prelink_git.bb b/meta/recipes-devtools/prelink/prelink_git.bb
index 0f6d16e005..c5eaedd4d9 100644
--- a/meta/recipes-devtools/prelink/prelink_git.bb
+++ b/meta/recipes-devtools/prelink/prelink_git.bb
@@ -31,7 +31,9 @@ SRC_URI = "git://git.yoctoproject.org/prelink-cross.git;branch=cross_prelink \
            file://prelink.conf \
            file://prelink.cron.daily \
            file://prelink.default \
-           file://macros.prelink"
+           file://macros.prelink \
+           file://0001-src-dso.c-use-ehdr.e_shstrndx-as-index.patch \
+"
 UPSTREAM_CHECK_COMMITS = "1"
 
 TARGET_OS_ORIG := "${TARGET_OS}"