From 0c5028faea7e5c08c920f8ea31f02e7923b8c2d8 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Wed, 18 Dec 2013 21:48:57 +0100 Subject: daemon: Fix 'HashSink::currentHash()'. Before that, calls to 'HashSink::currentHash()' would eventually lead to a segfault because the underlying gcrypt handle has been closed. (Note that this method is only used via 'importPaths' and 'exportPath', though.) * nix/libutil/gcrypt-hash.hh (struct guix_hash_context): Add a constructor and a copy constructor; move out of 'extern "C"'. * nix/libutil/gcrypt-hash.cc (guix_hash_final): Clear 'md_handle' upon exit. * nix/sync-with-upstream (top_srcdir): Change hash.{cc,hh} to read 'struct Ctx' instead of 'union Ctx'. --- nix/libutil/gcrypt-hash.cc | 1 + nix/libutil/gcrypt-hash.hh | 17 ++++++++++++++--- nix/sync-with-upstream | 8 ++++++++ 3 files changed, 23 insertions(+), 3 deletions(-) diff --git a/nix/libutil/gcrypt-hash.cc b/nix/libutil/gcrypt-hash.cc index 553f633b93..c4ae7bfcc2 100644 --- a/nix/libutil/gcrypt-hash.cc +++ b/nix/libutil/gcrypt-hash.cc @@ -45,6 +45,7 @@ guix_hash_final (void *resbuf, struct guix_hash_context *ctx, memcpy (resbuf, gcry_md_read (ctx->md_handle, algo), gcry_md_get_algo_dlen (algo)); gcry_md_close (ctx->md_handle); + ctx->md_handle = NULL; } } diff --git a/nix/libutil/gcrypt-hash.hh b/nix/libutil/gcrypt-hash.hh index d93a6eb881..11f061159f 100644 --- a/nix/libutil/gcrypt-hash.hh +++ b/nix/libutil/gcrypt-hash.hh @@ -23,17 +23,28 @@ #include #include -extern "C" { - struct guix_hash_context { + /* This copy constructor is needed in 'HashSink::currentHash()' where we + expect the copy of a 'Ctx' object to yield a truly different context. */ + guix_hash_context (guix_hash_context &ref) + { + if (ref.md_handle == NULL) + md_handle = NULL; + else + gcry_md_copy (&md_handle, ref.md_handle); + } + + /* Make sure 'md_handle' is always initialized. */ + guix_hash_context (): md_handle (NULL) { }; + gcry_md_hd_t md_handle; }; +extern "C" { extern void guix_hash_init (struct guix_hash_context *ctx, int algo); extern void guix_hash_update (struct guix_hash_context *ctx, const void *buffer, size_t len); extern void guix_hash_final (void *resbuf, struct guix_hash_context *ctx, int algo); - } diff --git a/nix/sync-with-upstream b/nix/sync-with-upstream index 535763d602..bb3a68b917 100755 --- a/nix/sync-with-upstream +++ b/nix/sync-with-upstream @@ -70,3 +70,11 @@ cp -v "$top_srcdir/nix-upstream/AUTHORS" "$top_srcdir/nix" # Substitutions. sed -i "$top_srcdir/nix/libstore/gc.cc" \ -e 's|/nix/find-runtime-roots\.pl|/guix/list-runtime-roots|g' + +# Our 'guix_hash_context' structure has a copy constructor, specifically to +# handle the use case in 'HashSink::currentHash()' where the copy of the +# context is expected to truly copy the underlying hash context. The copy +# constructor cannot be used in 'Ctx' if that's a union, so turn it into a +# structure (we can afford to two wasted words.) +sed -i "$top_srcdir/nix/libutil/hash".{cc,hh} \ + -e 's|union Ctx|struct Ctx|g' -- cgit v1.2.3