[Libguestfs] [PATCH nbdkit nbd] nbd: Unsuccessful attempt to fix memory leak.

Hi Eric, There's a memory leak in the nbd client. The message (below) is not very useful because somehow debuginfo is missing in the plugin. However it's easily reproducible by doing: make check-valgrind TESTS=test-nbd I tried the attached patch to fix what I thought was the bug, but sadly the fix doesn't work for me :-( So I guess something else is going on, but it does look as if the transactions list also needs to be freed. Rich. ==20307== ==20307== HEAP SUMMARY: ==20307== in use at exit: 2,267 bytes in 23 blocks ==20307== total heap usage: 2,298 allocs, 2,275 frees, 307,606 bytes allocated ==20307== ==20307== 96 bytes in 3 blocks are definitely lost in loss record 4 of 10 ==20307== at 0x4C2FA1E: calloc (vg_replace_malloc.c:711) ==20307== by 0x77EBBAF: ??? ==20307== by 0x77EBD17: ??? ==20307== by 0x40595C: handle_request (connections.c:894) ==20307== by 0x40595C: recv_request_send_reply (connections.c:1061) ==20307== by 0x405AE7: connection_worker (connections.c:200) ==20307== by 0x55DC55A: start_thread (in /usr/lib64/libpthread-2.26.9000.so) ==20307== by 0x58E85AE: clone (in /usr/lib64/libc-2.26.9000.so) ==20307== ==20307== 320 bytes in 10 blocks are definitely lost in loss record 9 of 10 ==20307== at 0x4C2FA1E: calloc (vg_replace_malloc.c:711) ==20307== by 0x77EBBAF: ??? ==20307== by 0x77EBD98: ??? ==20307== by 0x405986: handle_request (connections.c:884) ==20307== by 0x405986: recv_request_send_reply (connections.c:1061) ==20307== by 0x405AE7: connection_worker (connections.c:200) ==20307== by 0x55DC55A: start_thread (in /usr/lib64/libpthread-2.26.9000.so) ==20307== by 0x58E85AE: clone (in /usr/lib64/libc-2.26.9000.so) ==20307== ==20307== LEAK SUMMARY: ==20307== definitely lost: 416 bytes in 13 blocks ==20307== indirectly lost: 0 bytes in 0 blocks ==20307== possibly lost: 0 bytes in 0 blocks ==20307== still reachable: 411 bytes in 5 blocks ==20307== suppressed: 1,440 bytes in 5 blocks ==20307== Reachable blocks (those to which a pointer was found) are not shown. ==20307== To see them, rerun with: --leak-check=full --show-leak-kinds=all ==20307== ==20307== For counts of detected and suppressed errors, rerun with: -v ==20307== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 3 from 3)