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<pder>stikonas: I was trying to debug some segfaults with bash and found that if I try to simply run bash from outside the chroot it segfaults in make_variable_value()

<stikonas[m]>That's C function in bash source?

<pder>yeah

<pder>Program received signal SIGSEGV, Segmentation fault.

<pder>0x08076487 in make_variable_value () at variables.c:3017

<pder>it doesnt launch interactively for me

<stikonas[m]>Hmm, that is strange...

<stikonas[m]>pder: I just ried running bash 5 outside chroot and it works here

<pder>This is with bash-5.2.15?

<stikonas[m]>Yes

<stikonas[m]>I just unpacked that .tar.bz2 binary package and ran it interactively

<pder>interesting, not sure yet whats going on then

<pder>do you see gnulib-tool segfaults with bash?

<pder>if you run in a chroot you should be able to see them running dmesg

<stikonas>pder: I think I saw something in the logs...

<stikonas>though somehow everything still works even if gnulib-tool segfaults

<stikonas>which is a bit strange

<stikonas>or maybe because of original files in the tarball

<stikonas>they just don't get regenerated

<stikonas>pder: yes, I can see stuff like "conftest[92274]: segfault at 0 ip 00000000080486e8 sp 00000000ffc28560 error 4 in conftest[8048000+3000] likely on CPU 0 (core 0, socket 0)" in dmesg

<pder>stikonas: with latest commit in master, I ran ./rootfs.py --chroot --preserve and commented out everything in run.sh after building bash

<pder>f096b8e99ed5a93e350f860af2428e6d4e3ccbcf8133fe06fb2dd5ede52e1005 bash

<pder>thats the sha256sum of bash

<pder>If i try to run it segfaults

<pder>Just to be clear, with no arguments bash segfaults

<pder>I am running it in live-bootstrap/tmp/sysa/usr/bin

<fossy>hey, stikonas, when you get time could you please review #258 (no rush of course, just wanna make sure you know it exists)

<fossy>pder: i have the same bash and i cannot repro

<fossy>what kernel are you running on? can you get a core dump?

<fossy>core dump might not be useful if its not compiled with -g

<fossy>umm, also try env - live-bootstrap/tmp/sysa/usr/bin

<fossy>see if something in your env is breaking

<stikonas[m]>fossy: oh I briefly skimmed through it already. Seemed fine but I wanted to look a bit more carecully and forgot...

<pder>ok so apparently bash doesnt crash with run as root, but as my normal user it does- even though I have execute permissions on it

<stikonas[m]>And with empty env?

<stikonas[m]>Something is strange in your environment...

<stikonas>and id doesn't segfault here either

<stikonas>though given that is segfaults in live-bootstrap, there must be something buggy in it

IRC channel logs

2023-03-07.log