‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Saturday, May 23, 2020 5:22 PM, Bernhard Übelacker <bernha...@mailbox.org> wrote:
> Dear Maintainer, hello Mehturt, > I guess the missing debug information is contained in libcurl3-dbg [1]. > > I tried to find out to which line this address in Mehturt's backtrace > points to and came to this location: > > (gdb) bt > #0 0x00007ffff77cd4d7 in Curl_close (data=0x55555579f6c0) at url.c:399 > #1 0x000055555555874b in HttpsMethod::~HttpsMethod (this=0x7fffffffe470, > __in_chrg=<optimized out>) at ./methods/https.cc:538 > #2 main (argv=<optimized out>) at ./methods/https.cc:546 > > https://sources.debian.org/src/curl/7.52.1-5+deb9u10/lib/url.c/#L399 > https://sources.debian.org/src/apt/1.4.10/methods/https.cc/#L538 > > In my opinion the instruction "mov 0x60(%rbx),%rdi" is executed, for Mehturt, > while $rbx contains no valid pointer. > > The crash did not show up in my test VM. Attached an example debug session > to debug to this location. > > @Mehturt: maybe you can still install libcurl3-dbg and inspect the core again. > (Maybe adding a "display/i $pc" and "print/x $rbx", before any "bt full") Thank you Bernhard, indeed after installing libcurl3-dbg the backtrace looks similar to yours. (gdb) display/i $pc 1: x/i $pc => 0x7f0d6c04f4d7 <Curl_close+23>: mov 0x60(%rbx),%rdi (gdb) print/x $rbx $1 = 0xaf7e8480 (gdb) bt full #0 Curl_close (data=0xaf7e8480) at url.c:399 m = <optimized out> #1 0x00005638ad9bf74b in HttpsMethod::~HttpsMethod (this=0x7ffe4abe9690, __in_chrg=<optimized out>) at ./methods/https.cc:538 No locals. #2 main (argv=<optimized out>) at ./methods/https.cc:546 Binary = "https.bin+https" m.
