[Bug demangler/98889] New: stack overflow in cxxfilt, peek, rust-demangle.c:85

[featherrain26 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98889

            Bug ID: 98889
           Summary: stack overflow in cxxfilt, peek, rust-demangle.c:85
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: demangler
          Assignee: unassigned at gcc dot gnu.org
          Reporter: featherrain26 at gmail dot com
  Target Milestone: ---

Created attachment 50085
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50085&action=edit
POC

Hi, there.

There is a stack overflow in the newest version(2eda57ef) of cxxfilt,
rust-demangle.c:85 related to path demangling, which directly causes a
segmentation fault.

To reproduce, run
cxxfilt < poc

Here is the trace reported by ASAN:
ASAN:SIGSEGV
=================================================================
==52498==ERROR: AddressSanitizer: stack-overflow on address 0x7ffeeb551ff8 (pc
0x0000009768c0 bp 0x7ffeebd4f8b0 sp 0x7ffeeb551ff8 T0)
    #0 0x9768bf in peek ../../libiberty/rust-demangle.c:85
    #1 0x9768bf in next ../../libiberty/rust-demangle.c:105
    #2 0x9768bf in demangle_path ../../libiberty/rust-demangle.c:674

SUMMARY: AddressSanitizer: stack-overflow ../../libiberty/rust-demangle.c:85
peek
==52498==ABORTING