On Sun, 2016-10-23 at 10:25 -0700, Kevin Cernekee wrote:
Prematurely matching up the stripped and unstripped .strtab sections
in the "Match each debuginfo" loop can lead to a case where sec->outscn
gets populated for the stripped .strtab, which we normally want to
ignore. This causes the .strtab override in the "Make sure each main
file section" loop to be skipped, so the code winds up using indices
from the unstripped .symtab to look up strings in the stripped .strtab.
This returns incorrect strings for a little while, and then fails
catastrophically when it tries to read past the end of the (smaller)
stripped file's .strtab section:
eu-unstrip: invalid string offset in symbol 
Fix this by adding logic to the "Match each debuginfo" loop to
treat the unstripped .strtab, .shstrtab, and .symtab sections
essentially the same way.
Looks good. Thanks for the analysis and the fix.
Applied to git master.
The new logic will break if the .strtab section shows up earlier
the .symtab section. We will assume this never happens in practice.
grin. This screams for someone to show up with such a file tomorrow :)
But in practice this indeed doesn't happen because all tools create the
sections in order. If someone does create such a file with the sections
reversed we'll have to add another pass over the section headers.
Signed-off-by: Kevin Cernekee <cernekee(a)chromium.org>