Bug#1055750: gfortran: [armhf] Yield SIGBUS when compiling with -fstack-clash-protection

[Rafael Laboissière]

* Emanuele Rocca <e...@debian.org> [2023-11-14 12:01]:

On 2023-11-13 05:13, Rafael Laboissière wrote:

The attached file bug-1055750.tgz contains a minimal code that
triggers the bug on an armhf system

 armhf: /usr/lib/arm-linux-gnueabihf
 armel: /usr/lib/arm-linux-gnueabi
 arm64: /usr/lib/aarch64-linux-gnu

I'll see if I can find out more.

Thanks! For the record I can reproduce the issue in a armhf chroot, but *not* on armel and arm64. The only thing to change in the reproducer is the -I argument to gfortran:

Thanks for the followup, Emanuele.



    (gdb) run -dev ps -o /dev/null
    Starting program: /home/rafael/bug-1055750/x09f -dev ps -o /dev/null
    [Thread debugging using libthread_db enabled]
    Using host libthread_db library 
"/lib/arm-linux-gnueabihf/libthread_db.so.1".

    Program received signal SIGSEGV, Segmentation fault.
    x09f::mypltr2 (x=0, y=1, xt=0, yt=7.300765e-43) at x09f.f90:48
    48              yt = tr(1)



Best,

Rafael Laboissière

I have investigated the issue a little bit deeper. Please, find here attached a new tarball with a simplified version of the x09f.f90 file, that still triggers the bug. Running the resulting executable with gbd, yields the following: In this new code, there are two private functions mypltr1 and mypltr2. The bug only happens when the latter is invoked, in which a value coming from the global variable tr is assigned to yt. In mypltr1, the assignment is done to xt, instead of yt, and no segfault is triggered.

bug-1055750.tgz
Description: application/gtar-compressed