libc: FORTIFY: strncpy: detected read past end of 32-byte buffer about lvm2 HOT 4 CLOSED

Hi

It's true that using 'sizeof(vgid) - 1' or ID_LEN would be sufficient here,
but I can't imagine how it can cause any crashing of your app ???

Still the buffer is sized as ID_LEN+1 and '\0' is written after the call strncpy().

Can you rather share you 'coredump' trace or at least -vvvv log
before your execution crashes - as it looks like reason might be somewhere else.

from lvm2.

The write side is fine as you say, its the read from vg->id.uuid that whilst is normally fine, it reads an extra byte which is later overwritten. In the specific case of running within the android recovery context (which enforces the use of FORTIFY) does a test on both the read and write side of strncpy and so causes the crash.

from lvm2.

Ahh ok - so it's purely crashing your enforced fortified build - not a normal build - since the access is normally embedded into a volume_group structure so it should not cause any troubles.
I'll push minor change later on.

from lvm2.

Changed upstream with this commit:
https://listman.redhat.com/archives/lvm-devel/2021-August/msg00016.html

from lvm2.