https://bugzilla.suse.com/show_bug.cgi?id=1200447 Bug ID: 1200447 Summary: iproute2 - pmtudisc - "stack smashing detected" Classification: openSUSE Product: openSUSE Distribution Version: Leap 15.4 Hardware: x86-64 OS: openSUSE Leap 15.4 Status: NEW Severity: Minor Priority: P5 - None Component: Kernel Assignee: kernel-bugs@opensuse.org Reporter: georg.pfuetzenreuter@suse.com QA Contact: qa-bugs@suse.de Found By: --- Blocker: --- Hi, I am not sure if this is an upstream or a SUSE specific bug - I hope it's fine to report here. I think the `pmtudisc` option is only supported on `gre` and not on `ip6gre` interfaces. If this assumption is correct, I think the user should be informed about this, instead of being returned a "stack smashing detected" exception. #this is a ip6gre tunnel interface: $ ip t sh gre5 gre5: any/ip remote 42.2.23.72 local 0.0.0.1 ttl inherit tos inherit/0x02 nopmtudisc ikey 0 $ ip -6 t sh gre5 gre5: gre/ipv6 remote 2a02:1748:f7df:9c81::2 local 2a03:4000:55:d20::1 encaplimit 4 hoplimit 64 tclass 0x00 flowlabel 0x00000 (flowinfo 0x00000000)��� #attempting to change `nopmtudisc` to `pmtudisc` makes the program very unhappy $ sudo ip t c gre5 pmtudisc *** stack smashing detected ***: terminated fish: Job 1, 'sudo ip t c gre5 pmtudisc' terminated by signal SIGABRT (Abort) On a "regular" `gre` interface, it works fine. #this is a gre tunnel interface: $ ip t sh gre2 gre2: gre/ip remote 146.59.50.73 local 202.61.255.116 ttl 255 nopmtudisc #attempting to change `nopmtudisc` to `pmtudisc`... $ sudo ip t c gre2 pmtudisc #... succeeds: $ ip t sh gre2 gre2: gre/ip remote 146.59.50.73 local 202.61.255.116 ttl 255 Let me know if you need any further details or if you prefer me to report it at kernel.org. Thank you for reading! Best, Georg -- You are receiving this mail because: You are the assignee for the bug.