[PATCH v12 00/32] Validate binary before use

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi,

git://sourceware.org/git/archer.git
jankratochvil/gdbserverbuildid

The new file-locating parts are freshly coded, there are many possible future
improvements but I find the patchset as a minimal functional upstreamable
support for locating files from gdbserver build-ids.

It does not support build-ids from linux-nat and core files (as Fedora GDB
supports).  It also does not ask librpm for debuginfo-install suggestions.

There remain callers (like exec_file_and_symbols_resync) using various old
functions returning only 'char *filename;'.  This means if target binary has
build-id GDB will open the file twice - first to verify the build-id and second
to really start using that file.  The new functions returning 'struct
file_location file;' open such file as BFD only once.

It could cache already unsuccessfully searched paths.  With current sysroot
":target:" (that is ""+"target:") if target_filesystem_is_local() then all the
directories including debug-file-directory etc. will be searched twice (if no
matching file is found).  A quick but incomplete fix would be to only suppress
the second "target:" default sysroot part if target_filesystem_is_local().

This means that this patchset as is may be a performance regression.  But main
executable is only one and shared libraries should use the "fast" 'struct
file_location file;' code path.  But I haven't really traced/benchmarked it.

It could suppress repeated warning messages about non-matching build-ids.  It
may be related to the previous paragraph.

GDB could offload the build-id search in target: directories to gdbserver.
Currently if sysroot and/or debug-file-directory and other directory lists
contain multiple target:-starting paths GDB will ask gdbserver for each one
separately, each time sending vFile:open:..., multiple vFile:pread: etc.
(guessing), with each call costing one RTT.


Thanks,
Jan


v12
 * Add COREFILTER_ANON_PRIVATE and COREFILTER_ANON_SHARED to filterflags.
 * Free build_id in free_so(), not clear_so().
 * Add all the parts for locating (not just verifying) files by build-id.

v11
 * Use configure.tgt+ALL_TARGET_OBS instead of config/**.mh .
 * Move linux-maps.[ch] nat/ -> common/ .
 * Rename set solib-build-id-force -> set validate-build-id .
 * Rebase: Remove bfd_target_elf_flavour and elf_tdata->build_id requirement.
 * More descriptive warning messages.

v7
 * move linux-maps.[ch] common/->nat/ and target-utils.[ch] common/->target/
 * remove GDBSERVER #ifdefs
 * rebase on top of the new 'struct inferior *inf' parameter

v6
 * move also gdb_regex* to common/ as discussed above, also in config*.ac
 * skip_to_space{,_const}() were moved to common/
 * common/common-defs.h #include reordering
 * new passing of enum filterflags from linux_qxfer_libraries_svr4()
 * dropped refactoring of code moved to common/ that avoided GDB exceptions
 * new svr4_copy_library_list() needs to handle new so_list->build_id

v5
 * svr4_validate() considers missing local build-id as not-a-match
 * target_so_ops->validate() now returns not-a-match reason as a string
 * rename common/common-target.[ch] -> common/target-utils.[ch]
 * testcase runs (but broken) even on different-filesystem remote target
 * testcase simplified by using with_test_prefix()

v4
 * NEWS, doc/gdb.texinfo additions.
 * Used host-defs.h.
 * New set/show solib-build-id-force.
 * testsuite: Do not run on non-localhost remote targets.

v3
	[patchv3 0/8] Validate binary before use
	https://sourceware.org/ml/gdb-patches/2014-02/msg00842.html
	Message-ID: <20140227213229.GA21121@host2.jankratochvil.net>
 * Implemented the review comments I made.
 * Removed fetching build-id in solib-svr4.c for NAT run.

v2
	[PATCH 0/8] v2 - validate binary before use
	https://sourceware.org/ml/gdb-patches/2013-04/msg00472.html
	Message-ID: <1366127096-5744-1-git-send-email-ARistovski@qnx.com>

---

 gdb/testsuite/gdb.base/attach.exp              |    7 +
 gdb/testsuite/gdb.base/break-probes.exp        |    7 +
 gdb/testsuite/gdb.base/main-mismatch-mod.c     |   39 +++++
 gdb/testsuite/gdb.base/main-mismatch.c         |   39 +++++
 gdb/testsuite/gdb.base/main-mismatch.exp       |  158 +++++++++++++++++++
 gdb/testsuite/gdb.base/solib-mismatch-lib.c    |   30 ++++
 gdb/testsuite/gdb.base/solib-mismatch-libmod.c |   30 ++++
 gdb/testsuite/gdb.base/solib-mismatch.c        |   56 +++++++
 gdb/testsuite/gdb.base/solib-mismatch.exp      |  198 ++++++++++++++++++++++++
 9 files changed, 560 insertions(+), 4 deletions(-)
 create mode 100644 gdb/testsuite/gdb.base/main-mismatch-mod.c
 create mode 100644 gdb/testsuite/gdb.base/main-mismatch.c
 create mode 100644 gdb/testsuite/gdb.base/main-mismatch.exp
 create mode 100644 gdb/testsuite/gdb.base/solib-mismatch-lib.c
 create mode 100644 gdb/testsuite/gdb.base/solib-mismatch-libmod.c
 create mode 100644 gdb/testsuite/gdb.base/solib-mismatch.c
 create mode 100644 gdb/testsuite/gdb.base/solib-mismatch.exp