https://sourceware.org/bugzilla/show_bug.cgi?id=34833
Bug ID: 34833
Summary: GNU ld ns32k 32-bit relocation builds its overflow
mask with signed int shifts
Product: binutils
Version: 2.47
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: ld
Assignee: unassigned at sourceware dot org
Reporter: basavesh.shivakumar at wsu dot edu
Target Milestone: ---
Created attachment 17153
--> https://sourceware.org/bugzilla/attachment.cgi?id=17153&action=edit
repro
I'm reporting this bug on behalf of my team: Ananta Srikar Puranam, Emily West,
Dr. Swarn Priya, Dr. Peng Gao and Dr. Basavesh Ammanaghatta Shivakumar.
Summary
=======
GNU ld constructs the ns32k 32-bit signed relocation limit with the int
expression (1 << 31) - 1 at bfd/cpu-ns32k.c:671; current-head UBSan reports two
undefined operations on both routes while the one-byte DISP32 control is clean.
Reproduction
============
1. Download and extract
`bfd-ns32k-reloc-overflow-mask-shift-ubsan-reproducer.tar.gz`.
2. Run the following command with an ld.bfd or all-target `ld-new` binary that
supports the emulation used by the reproducer:
BFD=/path/to/ld-new sh repro.sh
The archive contains the fixed input files, independent controls, helper
scripts needed by `repro.sh`, and their checksums. The script uses a temporary
directory and does not modify the source tree.
Observed result
===============
GNU ld constructs the ns32k 32-bit signed relocation limit with the int
expression (1 << 31) - 1 at bfd/cpu-ns32k.c:671; current-head UBSan reports two
undefined operations on both routes while the one-byte DISP32 control is clean.
Expected result
===============
GNU ld should either produce the correct output or reject the input with a
normal diagnostic. It should not crash, hang, execute undefined behavior, read
outside an input-derived allocation, or produce the described malformed
output.
--
You are receiving this mail because:
You are on the CC list for the bug.
