I stumbled on a bug caused by the fact that a code path read
target_waitstatus::value::sig (expecting it to contain a gdb_signal
value) while target_waitstatus::kind was TARGET_WAITKIND_FORKED. This
meant that the active union field was in fact
target_waitstatus::value::related_pid, and contained a ptid. The read
signal value was therefore garbage, and that caused GDB to crash soon
after. Or, since that GDB was built with ubsan, this nice error
message:
/home/simark/src/binutils-gdb/gdb/linux-nat.c:1271:12: runtime error: load of value 2686365, which is not a valid value for type 'gdb_signal'
Despite being a large-ish change, I think it would be nice to make
target_waitstatus safe against that kind of bug. As already done
elsewhere (e.g. dynamic_prop), validate that the type of value read from
the union matches what is supposed to be the active field.
- Make the kind and value of target_waitstatus private.
- Make the kind initialized to TARGET_WAITKIND_IGNORE on
target_waitstatus construction. This is what most users appear to do
explicitly.
- Add setters, one for each kind. Each setter takes as a parameter the
data associated to that kind, if any. This makes it impossible to
forget to attach the associated data.
- Add getters, one for each associated data type. Each getter
validates that the data type fetched by the user matches the wait
status kind.
- Change "integer" to "exit_status", "related_pid" to "child_ptid",
just because that's more precise terminology.
- Fix all users.
That last point is semi-mechanical. There are a lot of obvious changes,
but some less obvious ones. For example, it's not possible to set the
kind at some point and the associated data later, as some users did.
But in any case, the intent of the code should not change in this patch.
This was tested on x86-64 Linux (unix, native-gdbserver and
native-extended-gdbserver boards). It was built-tested on x86-64
FreeBSD, NetBSD, MinGW and macOS. The rest of the changes to native
files was done as a best effort. If I forgot any place to update in
these files, it should be easy to fix (unless the change happens to
reveal an actual bug).
Change-Id: I0ae967df1ff6e28de78abbe3ac9b4b2ff4ad03b7
Since the two locations which check the debug arch are the same code currently, it is
a good idea to factor it out to a new function and just use that function from
aarch64_linux_get_debug_reg_capacity. This is also the first step to support
ARMv8.4 debug arch.
Make gdb_open_cloexec return a scoped_fd, to encourage using automatic
management of the file descriptor closing. Except in the most trivial
cases, I changed the callers to just release the fd, which retains their
existing behavior. That will allow the transition to using scoped_fd
more to go gradually, one caller at a time.
Change-Id: Ife022b403f96e71d5ebb4f1056ef6251b30fe554
I wanted to find, and potentially modify, all the spots where the
'tid' parameter to the ptid_t constructor was used. So, I temporarily
removed this parameter and then rebuilt.
In order to make it simpler to search through the "real" (nonzero)
uses of this parameter, something I knew I'd have to do multiple
times, I removed any ", 0" from constructor calls.
Co-Authored-By: John Baldwin <jhb@FreeBSD.org>
On a Windows build locally, watchpoints started failing. I tracked
this down to x86_dr_low_get_addr returning an 'unsigned long'... in
this particular build, this is a 32-bit type, but the inferior is a
64-bit program.
This patch fixes the problem by changing the return type. No other
change is required, because this matches the function pointer in
struct x86_dr_low_type.
Same idea as the previous patch, but for m_cwd.
To keep things consistent across the board, change get_inferior_cwd as
well, which is shared with GDBserver. So update the related GDBserver
code too.
Change-Id: Ia2c047fda738d45f3d18bc999eb67ceb8400ce4e
I'm debugging why GDB crashes on OpenBSD/amd64, turns out it's because
x86_dr_low.get_status is nullptr. It would have been useful to be able
to break on x86_dr_low_get_status, so I thought it would be a good
reason to convert these function-like macros into functions.
Change-Id: Ic200b50ef8455b4697bc518da0fa2bb704cf4721
Since GDB is written in C++ now, we don't need struct/union typedefs
any more. Remove them from nat/amd64-linux-siginfo.c.
gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <pedro@palves.net>
* nat/amd64-linux-siginfo.c (union nat_sigval): Rename to ...
(nat_sigval_t): ... this and remove typedef of same name.
(struct nat_siginfo): Rename to ...
(nat_siginfo_t): ... this and remove typedef of same name.
(struct compat_sigval): Rename to ...
(compat_sigval_t): ... this and remove typedef of same name.
(struct compat_siginfo): Rename to ...
(compat_siginfo_t): ... this and remove typedef of same name.
(struct compat_x32_siginfo): Rename to ...
(compat_x32_siginfo_t): ... this and remove typedef of same name.
(amd64_linux_siginfo_fixup_common): Adjust.
Compiling GDB with current git Clang (future 13) fails with (among
other problems), this issue:
$ make nat/amd64-linux-siginfo.o
CXX nat/amd64-linux-siginfo.o
src/gdb/nat/amd64-linux-siginfo.c:590:35: warning: passing 4-byte aligned argument to 8-byte aligned parameter 1 of 'compat_x32_siginfo_from_siginfo' may result in an unaligned pointer access [-Walign-mismatch]
compat_x32_siginfo_from_siginfo ((struct compat_x32_siginfo *) inf,
^
1 warning generated.
The problem is that:
- The flagged code is casting to "struct compat_x32_siginfo" pointer
directly instead of to a pointer to the compat_x32_siginfo_t
typedef. The called function is declared with a
compat_x32_siginfo_t typedef pointer parameter.
- Only the typedef has the __aligned__ attribute.
Fix this by moving the attribute to the struct, so both struct and
typedef have the same alignment.
The next patch removes the typedefs.
gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <pedro@palves.net>
* nat/amd64-linux-siginfo.c (compat_x32_siginfo_t): Move
__attribute__ __aligned__ from the typedef to the struct.
I spotted some indentation issues where we had some spaces followed by
tabs at beginning of line, that I wanted to fix. So while at it, I did
a quick grep to find and fix all I could find.
gdb/ChangeLog:
* Fix tab after space indentation issues throughout.
Change-Id: I1acb414dd9c593b474ae2b8667496584df4316fd
I wrote a small script to spot a pattern of indentation mistakes I saw
happened in breakpoint.c. And while at it I ran it on all files and
fixed what I found. No behavior changes intended, just indentation and
addition / removal of curly braces.
gdb/ChangeLog:
* Fix some indentation mistakes throughout.
gdbserver/ChangeLog:
* Fix some indentation mistakes throughout.
Change-Id: Ia01990c26c38e83a243d8f33da1d494f16315c6e
I tried a build using the undefined behavior sanitizer, and gcc gave
this error:
In file included from /usr/include/string.h:495,
from ../gnulib/import/string.h:41,
from ../../binutils-gdb/gdb/../gdbsupport/common-defs.h:95,
from ../../binutils-gdb/gdb/nat/linux-osdata.c:20:
In function 'char* strncpy(char*, const char*, size_t)',
inlined from 'void time_from_time_t(char*, int, TIME_T)' at ../../binutils-gdb/gdb/nat/linux-osdata.c:923:15,
inlined from 'void time_from_time_t(char*, int, TIME_T)' at ../../binutils-gdb/gdb/nat/linux-osdata.c:911:1,
inlined from 'void linux_xfer_osdata_sem(buffer*)' at ../../binutils-gdb/gdb/nat/linux-osdata.c:1082:22:
/usr/include/bits/string_fortified.h:106:34: error: 'char* __builtin_strncpy(char*, const char*, long unsigned int)' specified bound 32 equals destination size [-Werror=stringop-truncation]
This patch fixes the problem by subtracting one from the length
parameter to strncpy.
I changed a couple of other similar functions -- gcc does not warn
about these, but I didn't see any substantial difference between the
different cases, and I think these are just latent warnings, to be
triggered in the future by a change to inlining heuristics.
gdb/ChangeLog
2021-05-17 Tom Tromey <tromey@adacore.com>
* nat/linux-osdata.c (user_from_uid, time_from_time_t)
(group_from_gid): Subtract one from strncpy length.
I was looking at some "set debug lin-lwp" logs, and saw that a thread
received the "Child exited" signal. It took me a moment to realize that
this was SIGCHLD. I then thought that it would be nice for
status_to_str to show the signal name (SIGCHLD) in addition to the
description "Child exited", since people are much more used to referring
to signals using their names.
Fortunately, libiberty contains a handy function to get the signal name
from the signal number, strsigno, use that.
The output of "set debug lin-lwp" now looks like:
[linux-nat] linux_nat_wait_1: waitpid 1209631 received SIGTRAP - Trace/breakpoint trap (stopped)
gdb/ChangeLog:
* nat/linux-waitpid.c (status_to_str): Show signal name.
Change-Id: I8ad9b1e744dd64461fd87b08d5c29f9ef97c4691
Instead of using a static buffer. This is safer, and we don't really
mind about any extra dynamic allocation here, since it's only used for
debug purposes.
gdb/ChangeLog:
* nat/linux-waitpid.c (status_to_str): Return std::string.
* nat/linux-waitpid.h (status_to_str): Likewise.
* linux-nat.c (linux_nat_post_attach_wait): Adjust.
(linux_nat_target::attach): Adjust.
(linux_handle_extended_wait): Adjust.
(wait_lwp): Adjust.
(stop_wait_callback): Adjust.
(linux_nat_filter_event): Adjust.
(linux_nat_wait_1): Adjust.
* nat/linux-waitpid.c (status_to_str): Adjust.
* nat/linux-waitpid.h (status_to_str): Adjust.
gdbserver/ChangeLog:
* linux-low.cc (linux_process_target::wait_for_event_filtered):
Adjust to status_to_str returning std::string.
Change-Id: Ia8aead70270438a5690f243e6faafff6c38ff757
Currently, in order to tell whether support for disabling address
space randomization on Linux is available, GDB checks if the
personality syscall works, at configure time. I.e., it does a run
test, instead of a compile/link test:
AC_RUN_IFELSE([PERSONALITY_TEST],
[have_personality=true],
[have_personality=false],
This is a bit bogus, because the machine the build is done on may not
(and is when you consider distro gdbs) be the machine that eventually
runs gdb. It would be better if this were a compile/link test
instead, and then at runtime, GDB coped with the personality syscall
failing. Actually, GDB already copes.
One environment where this is problematic is building GDB in a Docker
container -- by default, Docker runs the container with seccomp, with
a profile that disables the personality syscall. You can tell Docker
to use a less restricted seccomp profile, but I think we should just
fix it in GDB.
"man 2 personality" says:
This system call first appeared in Linux 1.1.20 (and thus first
in a stable kernel release with Linux 1.2.0); library support
was added in glibc 2.3.
...
ADDR_NO_RANDOMIZE (since Linux 2.6.12)
With this flag set, disable address-space-layout randomization.
glibc 2.3 was released in 2002.
Linux 2.6.12 was released in 2005.
The original patch that added the configure checks was submitted in
2008. The first version of the patch that was submitted to the list
called personality from common code:
https://sourceware.org/pipermail/gdb-patches/2008-June/058204.html
and then was moved to Linux-specific code:
https://sourceware.org/pipermail/gdb-patches/2008-June/058209.html
Since HAVE_PERSONALITY is only checked in Linux code, and
ADDR_NO_RANDOMIZE exists for over 15 years, I propose just completely
removing the configure checks.
If for some odd reason, some remotely modern system still needs a
configure check, then we can revert this commit but drop the
AC_RUN_IFELSE in favor of always doing the AC_LINK_IFELSE
cross-compile fallback.
gdb/ChangeLog:
* linux-nat.c (linux_nat_target::supports_disable_randomization):
Remove references to HAVE_PERSONALITY.
* nat/linux-personality.c: Remove references to HAVE_PERSONALITY.
(maybe_disable_address_space_randomization)
(~maybe_disable_address_space_randomizatio): Remove references to
HAVE_PERSONALITY.
* config.in, configure: Regenerate.
gdbserver/ChangeLog:
* linux-low.cc:
(linux_process_target::supports_disable_randomization): Remove
reference to HAVE_PERSONALITY.
* config.in, configure: Regenerate.
gdbsupport/ChangeLog:
* common.m4 (personality test): Remove.
The only callers of get_image_name are nat/windows-nat.c, so make it
static.
gdb/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* nat/windows-nat.h (get_image_name): Don't declare.
* nat/windows-nat.c (get_image_name): Now static.
This moves the new DLL-loading code into nat/windows-nat.c, and
changes both gdb and gdbserver to use the shared code. One
client-provided callback, handle_load_dll, is changed to allow the
code to be shared. This callback was actually never called from
nat/windows-nat.c; maybe I had planned to share more here and then
didn't finish... I'm not sure.
gdb/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* windows-nat.c (windows_nat::handle_load_dll): Update.
(windows_nat_target::get_windows_debug_event): Call
dll_loaded_event.
(windows_add_all_dlls, windows_add_dll): Move to
nat/windows-nat.c.
* nat/windows-nat.h (handle_load_dll): Change parameters.
(dll_loaded_event, windows_add_all_dlls): Declare.
* nat/windows-nat.c (windows_add_dll, windows_add_all_dlls): Move
from windows-nat.c.
(dll_loaded_event): New function.
gdbserver/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* win32-low.cc (do_initial_child_stuff): Update.
(windows_nat::handle_load_dll): Rename from win32_add_one_solib.
Change parameter type.
(win32_add_dll, win32_add_all_dlls)
(windows_nat::handle_load_dll): Remove.
(get_child_debug_event): Call dll_loaded_event.
This changes gdbserver to use the function indirection code that was
just moved into nat/windows-nat.[ch]. One additional function is used
by gdbserver that was not used by gdb.
gdb/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* nat/windows-nat.h (GenerateConsoleCtrlEvent): New define.
(GenerateConsoleCtrlEvent_ftype, GenerateConsoleCtrlEvent):
Declare.
* nat/windows-nat.c (GenerateConsoleCtrlEvent): Define.
(initialize_loadable): Initialize GenerateConsoleCtrlEvent.
gdbserver/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* win32-low.cc (GETPROCADDRESS): Remove.
(winapi_DebugActiveProcessStop, winapi_DebugSetProcessKillOnExit)
(winapi_DebugBreakProcess, winapi_GenerateConsoleCtrlEvent)
(winapi_Wow64SetThreadContext, win32_Wow64GetThreadContext)
(win32_Wow64SetThreadContext): Remove.
(win32_set_thread_context, do_initial_child_stuff)
(win32_process_target::attach, win32_process_target::detach):
Update.
(winapi_EnumProcessModules, winapi_EnumProcessModulesEx)
(winapi_GetModuleInformation, winapi_GetModuleInformationA):
Remove.
(win32_EnumProcessModules, win32_EnumProcessModulesEx)
(win32_GetModuleInformation, win32_GetModuleInformationA):
Remove.
(load_psapi): Remove.
(win32_add_dll, win32_process_target::request_interrupt): Update.
(initialize_low): Call initialize_loadable.
gdb and gdbserver both look for functions in some Windows DLLs at
runtime. This patch moves this code out of gdb and into
nat/windows-nat, so it can be shared by both programs.
gdb/ChangeLog
2021-04-30 Tom Tromey <tromey@adacore.com>
* windows-nat.c: Move code to nat/windows-nat.[ch].
(_initialize_windows_nat): Call initialize_loadable.
* nat/windows-nat.h (AdjustTokenPrivileges)
(DebugActiveProcessStop, DebugBreakProcess)
(DebugSetProcessKillOnExit, EnumProcessModules)
(EnumProcessModulesEx, GetModuleInformation)
(GetModuleFileNameExA, GetModuleFileNameExW)
(LookupPrivilegeValueA, OpenProcessToken, GetConsoleFontSize)
(GetCurrentConsoleFont, Wow64SuspendThread)
(Wow64GetThreadContext, Wow64SetThreadContext)
(Wow64GetThreadSelectorEntry): Move from windows-nat.c.
(AdjustTokenPrivileges_ftype)
(DebugActiveProcessStop_ftype, DebugBreakProcess_ftype)
(DebugSetProcessKillOnExit_ftype, EnumProcessModules_ftype)
(EnumProcessModulesEx_ftype, GetModuleInformation_ftype)
(GetModuleFileNameExA_ftype, GetModuleFileNameExW_ftype)
(LookupPrivilegeValueA_ftype, OpenProcessToken_ftype)
(GetConsoleFontSize_ftype)
(GetCurrentConsoleFont_ftype, Wow64SuspendThread_ftype)
(Wow64GetThreadContext_ftype, Wow64SetThreadContext_ftype)
(Wow64GetThreadSelectorEntry_ftype): Likewise.
(initialize_loadable): Declare.
* nat/windows-nat.c (AdjustTokenPrivileges)
(DebugActiveProcessStop, DebugBreakProcess)
(DebugSetProcessKillOnExit, EnumProcessModules)
(EnumProcessModulesEx, GetModuleInformation, GetModuleFileNameExA)
(GetModuleFileNameExW, LookupPrivilegeValueA, OpenProcessToken)
(GetCurrentConsoleFont, GetConsoleFontSize, Wow64SuspendThread)
(Wow64GetThreadContext, Wow64SetThreadContext)
(Wow64GetThreadSelectorEntry): Define.
(bad, bad_GetCurrentConsoleFont, bad_GetConsoleFontSize): Move
from windows-nat.c.
(initialize_loadable): Likewise, and rename.
The support for WinCE was removed with commit 84b300de36 ("gdbserver:
remove support for ARM/WinCE"). There is some leftover code for WinCE
support, guarded by the _WIN32_WCE macro, which I didn't know of at the
time.
I didn't remove the _WIN32_WCE references in the tests, because in
theory we still support the WinCE architecture in GDB (when debugging
remotely). So someone could run a test with that (although I'd be
really surprised).
gdb/ChangeLog:
* nat/windows-nat.c: Remove all code guarded by _WIN32_WCE.
* nat/windows-nat.h: Likewise.
gdbserver/ChangeLog:
* win32-low.cc: Remove all code guarded by _WIN32_WCE.
* win32-low.h: Likewise.
Change-Id: I7a871b897e2135dc195b10690bff2a01d9fac05a
Similarly to commit 665af52ec2, fix a build
failure seen with an updated glibc, due to the enum/constant mismatch.
The old include file order eventually makes asm/ptrace.h get included before
sys/ptrace.h.
This patch fixes it. Seems fairly obvious and I'll push it shortly.
gdb/ChangeLog:
2021-04-09 Luis Machado <luis.machado@linaro.org>
* nat/aarch64-mte-linux-ptrace.c: Update include file order.
The patch implements the memory tagging target hooks for AArch64, so we
can handle MTE.
gdb/ChangeLog:
2021-03-24 Luis Machado <luis.machado@linaro.org>
* Makefile.in (ALL_64_TARGET_OBS): Add arch/aarch64-mte-linux.o.
(HFILES_NO_SRCDIR): Add arch/aarch64-mte-linux.h and
nat/aarch64-mte-linux-ptrace.h.
* aarch64-linux-nat.c: Include nat/aarch64-mte-linux-ptrace.h.
(aarch64_linux_nat_target) <supports_memory_tagging>: New method
override.
<fetch_memtags>: New method override.
<store_memtags>: New method override.
(aarch64_linux_nat_target::supports_memory_tagging): New method.
(aarch64_linux_nat_target::fetch_memtags): New method.
(aarch64_linux_nat_target::store_memtags): New method.
* arch/aarch64-mte-linux.c: New file.
* arch/aarch64-mte-linux.h: Include gdbsupport/common-defs.h.
(AARCH64_MTE_GRANULE_SIZE): Define.
(aarch64_memtag_type): New enum.
(aarch64_mte_get_tag_granules): New prototype.
* configure.nat (NATDEPFILES): Add nat/aarch64-mte-linux-ptrace.o.
* configure.tgt (aarch64*-*-linux*): Add arch/aarch64-mte-linux.o.
* nat/aarch64-mte-linux-ptrace.c: New file.
* nat/aarch64-mte-linux-ptrace.h: New file.
This patch adds the required ptrace request definitions into a new include
file that will be used by the next patches.
They are PTRACE_PEEKMTETAGS and PTRACE_POKEMTETAGS.
gdb/ChangeLog:
2021-03-24 Luis Machado <luis.machado@linaro.org>
* Makefile.in (HFILES_NO_SRCDIR): Add nat/aarch64-mte-linux-ptrace.h.
* nat/aarch64-mte-linux-ptrace.h: New file.
I added the same comment for nat/aarch64-linux-hw-point.c yesterday.
Christian suggested adding the comment for the other file that I had
identified as including both <sys/ptrace.h> and <asm/ptrace.h>.
I searched the sources in gdb/, but found no other files which include
both of these headers.
If possible, I would prefer to see us use <sys/ptrace.h> when possible,
however, from past experience, I've found that this file does not always
contain all of the constants, etc. required by the particular source
file.
gdb/ChangeLog:
* nat/aarch64-sve-linux-ptrace.h: Add comment regarding include
order for <sys/ptrace.h> and <asm/ptrace.h>.
Due to a recent glibc header file change, the file
nat/aarch64-linux-hw-point.c no longer builds on Fedora rawhide.
An enum for PTRACE_SYSEMU is now provided by <sys/ptrace.h>. In the
past, PTRACE_SYSEMU was defined only in <asm/ptrace.h>. This is
what it looks like...
In <asm/ptrace.h>:
#define PTRACE_SYSEMU 31
In <sys/ptrace.h>:
enum __ptrace_request
{
...
PTRACE_SYSEMU = 31,
#define PT_SYSEMU PTRACE_SYSEMU
...
}
When <asm/ptrace.h> and <sys/ptrace.h> are both included in a source
file, we run into the following build problem when the former is
included before the latter:
In file included from nat/aarch64-linux-hw-point.c:26:
/usr/include/sys/ptrace.h:86:3: error: expected identifier before numeric constant
86 | PTRACE_SYSEMU = 31,
| ^~~~~~~~~~~~~
(There are more errors after this one too.)
The file builds without error when <asm/ptrace.h> is included after
<sys/ptrace.h>. I found that this is already done in
nat/aarch64-sve-linux-ptrace.h (which is included by
nat/aarch64-linux-ptrace.c).
I've tested this change on Fedora rawhide and Fedora 33, both
running on an aarch64 machine.
gdb/ChangeLog:
* nat/aarch64-linux-hw-point.c: Include <asm/ptrace.h> after
<sys/ptrace.h>.
On Fedora rawhide, after updating to glibc-2.33, I'm seeing the
following build failure:
CXX nat/amd64-linux-siginfo.o
In file included from /usr/include/bits/sigstksz.h:24,
from /usr/include/signal.h:315,
from ../gnulib/import/signal.h:52,
from /ironwood1/sourceware-git/rawhide-gnulib/bld/../../worktree-gnulib/gdbserver/../gdb/nat/amd64-linux-siginfo.c:20:
../gnulib/import/unistd.h:663:3: error: #error "Please include config.h first."
663 | #error "Please include config.h first."
| ^~~~~
glibc-2.33 has changed signal.h to now include <bits/sigstksz.h> which,
in turn, includes <unistd.h>. For a gdb build, this causes the gnulib
version of unistd.h to be pulled in first. The build failure shown
above happens because gnulib's config.h has not been included before
the include of <signal.h>.
The fix is simple - we just rearrange the order of the header file
includes to make sure that gdbsupport/commondefs.h is included before
attempting to include signal.h. Note that gdbsupport/commondefs.h
includes <gnulib/config.h>.
Build and regression tested on Fedora 33. On Fedora rawhide, GDB
builds again.
gdb/ChangeLog:
* nat/amd64-linux-siginfo.c: Include "gdbsupport/common-defs.h"
(which in turn includes <gnulib/config.h>) before include
of <signal.h>.
This changes windows-nat.c and nat/windows-nat.c to use the new
debug_prefixed_printf_cond facility. I tried this out on a Windows
build and I think it makes the output look a little nicer.
2021-01-26 Tom Tromey <tromey@adacore.com>
* windows-nat.c (DEBUG_EXEC, DEBUG_EVENTS, DEBUG_MEM)
(DEBUG_EXCEPT): Use debug_prefixed_printf_cond.
(windows_init_thread_list, windows_nat::handle_load_dll)
(windows_nat::handle_unload_dll, windows_nat_target::resume)
(windows_nat_target::resume)
(windows_nat_target::get_windows_debug_event)
(windows_nat_target::interrupt, windows_xfer_memory)
(windows_nat_target::close): Update.
* nat/windows-nat.c (DEBUG_EVENTS): Use
debug_prefixed_printf_cond.
(matching_pending_stop, fetch_pending_stop)
(continue_last_debug_event): Update.
When running test-case gdb.arch/i386-mpx-sigsegv.exp with target board
unix/-m32, we run into:
...
(gdb) continue^M
Continuing.^M
Saw a #BR! status 1 at 0x8048c2d^M
^M
Program received signal SIGSEGV, Segmentation fault^M
Upper bound violation while accessing address 0x0804c15c^M
Bounds: [lower = 0x00000000, upper = 0x00000000].^M
0x08048a4f in lower (p=0x804c160, a=0x804c180, b=0x804c1a0, c=0x804c1c0, \
d=0x804c1e0, len=1) at i386-mpx-sigsegv.c:79^M
79 value = *(p - len);^M
(gdb) FAIL: gdb.arch/i386-mpx-sigsegv.exp: MPX signal segv Lower: 0
...
The problem is that lower and upper in the Bounds message are 0x0, which is
caused by $_siginfo._sifields._sigfault._addr_bnd.{_lower,_upper} evaluating
to 0x0.
Fix this by copying the si_lower/si_upper fields in
compat_siginfo_from_siginfo.
Tested on x86_64-linux, with target board unix/-m32.
gdb/ChangeLog:
2021-01-18 Tom de Vries <tdevries@suse.de>
PR tdep/27172
* nat/amd64-linux-siginfo.c (cpt_si_lower, cpt_si_upper, SEGV_BNDERR):
New macro.
(compat_siginfo_from_siginfo): Copy cpt_si_lower and cpt_si_upper
for SEGV_BNDERR.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
The FPSIMD dump in signal frames and ptrace FPSIMD dump in the SVE context
structure follows the target endianness, whereas the SVE dumps are
endianness-independent (LE).
Therefore, when the system is in BE mode, we need to reverse the bytes
for the FPSIMD data.
Given the V registers are larger than 64-bit, I've added a way for value
bytes to be set, as opposed to passing a 64-bit fixed quantity. This fits
nicely with the unwinding *_got_bytes function and makes the trad-frame
more flexible and capable of saving larger registers.
The memory for the bytes is allocated via the frame obstack, so it gets freed
after we're done inspecting the frame.
gdb/ChangeLog:
2020-12-10 Luis Machado <luis.machado@linaro.org>
* aarch64-linux-tdep.c (aarch64_linux_restore_vreg) New function.
(aarch64_linux_sigframe_init): Call aarch64_linux_restore_vreg.
* aarch64-tdep.h (V_REGISTER_SIZE): Move to ...
* arch/aarch64.h: ... here.
* nat/aarch64-sve-linux-ptrace.c: Include endian.h.
(aarch64_maybe_swab128): New function.
(aarch64_sve_regs_copy_to_reg_buf)
(aarch64_sve_regs_copy_from_reg_buf): Adjust FPSIMD entries.
* trad-frame.c (trad_frame_reset_saved_regs): Initialize
the data field.
(TF_REG_VALUE_BYTES): New enum value.
(trad_frame_value_bytes_p): New function.
(trad_frame_set_value_bytes): New function.
(trad_frame_set_reg_value_bytes): New function.
(trad_frame_get_prev_register): Handle register values saved as bytes.
* trad-frame.h (trad_frame_set_reg_value_bytes): New prototype.
(struct trad_frame_saved_reg) <data>: New field.
(trad_frame_set_value_bytes): New prototype.
(trad_frame_value_bytes_p): New prototype.
This eliminates the need to specify the return type when using
handle_eintr. We let the compiler deduce it for us.
Also, use lowercase for function parameter names. Uppercase should
only be used on template parameters.
gdb/ChangeLog:
* nat/linux-waitpid.c: Include "gdbsupport/eintr.h".
(my_waitpid): Use gdb::handle_eintr.
gdbserver/ChangeLog:
* netbsd-low.cc (netbsd_waitpid, netbsd_process_target::kill)
(netbsd_qxfer_libraries_svr4): Use gdb::handle_eintr without
explicit type.
gdbsupport/ChangeLog:
* eintr.h (handle_eintr): Replace Ret template parameter with
ErrorValType. Use it as type of the failure value. Deduce the
function's return type using decltype. Use lowercase for function
parameter names.
In case of repeated ptrace PT_IO call and returning the value of
transferred bytes equal to 0, do not return without setting
xfered_len.
gdb/ChangeLog:
* nat/netbsd-nat.c (write_memory, read_memory): Update.
Instead of sharing the native-only code with all BSDs with slightly
different semantics of the kernels, share the NetBSD-only behavior beteen
the NetBSD native and gdbserver setup.
NetBSD does not differentiate the address space I and D in the
operations (contrary to OpenBSD). NetBSD handles EACCES that integrates
with NetBSD specific PaX MPROTECT error handling.
Add a verbose message in the native client that an operation could be
cancelled due to PaX MPROTECT setup.
gdb/ChangeLog:
* nat/netbsd-nat.c (write_memory, read_memory): Add.
* nat/netbsd-nat.h (write_memory, read_memory): Likewise.
* nbsd-nat.c (nbsd_nat_target::xfer_partial): Update.
gdbserver/ChangeLog:
* netbsd-low.cc (netbsd_process_target::read_memory)
(netbsd_process_target::write_memory): Update.
When a WOW64 process triggers a breakpoint exception in 64bit code (which
happens when a 64bit gdb calls DebugBreakProcess for a 32bit target),
gdb ignores the breakpoint (because Wow64GetThreadContext can only report
the pc of 32bit code, and there is not int3 at this location).
But if these 64bit breakpoint exceptions are handled as SIGINT, gdb
doesn't check for int3, and always stops the target.
gdb/ChangeLog:
2020-09-23 Hannes Domani <ssbssa@yahoo.de>
* nat/windows-nat.c (handle_exception): Handle 64bit breakpoints
in WOW64 processes as SIGINT.
* nat/windows-nat.h: Make wow64_process a shared variable.
* windows-nat.c: Remove static wow64_process variable.
gdbserver/ChangeLog:
2020-09-23 Hannes Domani <ssbssa@yahoo.de>
* win32-low.cc: Remove local wow64_process variable.
* win32-low.h: Remove local wow64_process variable.
Do not free the last execd pathname as it will be used in
prepare_resume_reply(), after attaching a client side.
gdb/ChangeLog:
* fork-inferior.c (startup_inferior): Avoid double free.
Add generic function to enable debugger events in a process.
gdb/ChangeLog:
* netbsd-nat.h (netbsd_nat::enable_proc_events): Add.
* netbsd-nat.c: Include <sys/ptrace.h>.
* (netbsd_nat::enable_proc_events): Add.
The kernel has fixed this here:
https://lore.kernel.org/patchwork/patch/1029011/
We should do the same for GDB, which is still carrying an incorrect
definition of the macro. As stated in the kernel patch thread, this doesn't
actually change things because, luckily, the structs are of the same size.
gdb/ChangeLog:
2020-08-10 Luis Machado <luis.machado@linaro.org>
* nat/aarch64-sve-linux-sigcontext.h (SVE_PT_REGS_OFFSET): Use
struct user_sve_header instead of struct sve_context.
Writing to inferior_ptid in
windows_nat_target::get_windows_debug_event is just incorrect and not
necessary. We'll report the event to GDB's core, which then takes
care of switching inferior_ptid / current thread.
Related (see windows_nat_target::get_windows_debug_event), there's
also a "current_windows_thread" global that is just begging to get out
of sync with core GDB's current thread. This patch removes it.
gdbserver already does not have an equivalent global in win32-low.cc.
gdb/ChangeLog:
2020-06-18 Pedro Alves <palves@redhat.com>
* nat/windows-nat.c (current_windows_thread): Remove.
* nat/windows-nat.h (current_windows_thread): Remove.
* windows-nat.c (windows_nat_target::stopped_by_sw_breakpoint):
Adjust.
(display_selectors): Adjust to fetch the current
windows_thread_info based on inferior_ptid.
(fake_create_process): No longer write to current_windows_thread.
(windows_nat_target::get_windows_debug_event):
Don't set inferior_ptid or current_windows_thread.
(windows_nat_target::wait): Adjust to not rely on
current_windows_thread.
(do_initial_windows_stuff): Now a method of windows_nat_target.
Switch to the last_ptid thread.
(windows_nat_target::attach): Adjust.
(windows_nat_target::detach): Use switch_to_no_thread instead of
writing to inferior_ptid directly.
(windows_nat_target::create_inferior): Adjust.
I sometimes encountered a weird breakpoint failure when using start:
(gdb) start
Temporary breakpoint 2 at 0x40162d: file gdb-25911.c, line 4.
Starting program: C:\src\tests\gdb-25911.exe
Warning:
Cannot insert breakpoint 2.
Cannot access memory at address 0x401628
After trying a lot of combinations, I found a way to reproduce it:
(gdb) file gdb-25987.exe
Reading symbols from gdb-25987.exe...
(gdb) start
Temporary breakpoint 1 at 0x401638: file gdb-25987.cpp, line 13.
Starting program: C:\src\tests\gdb-25987.exe
Temporary breakpoint 1, main () at gdb-25987.cpp:13
13 int main() {
(gdb) c
Continuing.
Program received signal SIGSEGV, Segmentation fault.
MyClass::call (this=0x3d20d0) at gdb-25987.cpp:8
8 *(char*)(nullptr) = 1;
(gdb) kill
Kill the program being debugged? (y or n) y
[Inferior 1 (process 1140) killed]
(gdb) file gdb-25911.exe
Load new symbol table from "gdb-25911.exe"? (y or n) y
Reading symbols from gdb-25911.exe...
(gdb) start
Temporary breakpoint 2 at 0x40162d: file gdb-25911.c, line 4.
Starting program: C:\src\tests\gdb-25911.exe
Warning:
Cannot insert breakpoint 2.
Cannot access memory at address 0x401628
Command aborted.
The actual failure was that ReadProcessMemory used a process handle that
was no longer valid.
And the underlying reason was that the windows_thread_info destructor
closes a thread handle that was provided earlier by WaitForDebugEvent.
But since this is not allowed (and it was actually already closed at this
point, and the handle value reused), this closed another still-needed handle.
gdb/ChangeLog:
2020-05-27 Hannes Domani <ssbssa@yahoo.de>
* nat/windows-nat.c (windows_thread_info::~windows_thread_info):
Don't close thread handle.
Some Intel processors implement a Branch Trace Store (BTS) which GDB
uses for reverse execution support via the "record btrace bts"
command.
I have been unable to find a description of a similar feature in a
recent (April 2020) AMD64 architecture reference:
https://www.amd.com/system/files/TechDocs/40332.pdf
While it is the case that AMD processors have an LBR (last branch
record) bit in the DebugCtl MSR, it seems that it affects only four
MSRs when enabled. The names of these MSRs are LastBranchToIP,
LastBranchFromIP, LastIntToIP, and LastIntFromIP. I can find no
mention of anything more extensive. While looking at an Intel
architecture document, I noticed that Intel's P6 family from the
mid-90s had registers of the same name.
Therefore...
This commit disables "record btrace bts" support in GDB for AMD
processors.
Using the test case from gdb.base/break.exp, the sessions
below show the expected behavior (run on a machine with an
Intel processor) versus that on a machine with an AMD processor.
The AMD processor in question is reported as follows by "lscpu":
AMD Ryzen Threadripper 2950X 16-Core Processor . Finally, I'll
note that the AMD machine is actually a VM, but I see similar
behavior on both the virtualization host and the VM.
Intel machine - Desired behavior:
[kevinb@mohave gdb]$ ./gdb -q testsuite/outputs/gdb.base/break/break
Reading symbols from testsuite/outputs/gdb.base/break/break...
(gdb) start
Temporary breakpoint 1 at 0x401179: file /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c, line 43.
Starting program: /home/kevinb/sourceware-git/native-build/bld/gdb/testsuite/outputs/gdb.base/break/break
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffd748, envp=0x7fffffffd758)
at /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c:43
43 if (argc == 12345) { /* an unlikely value < 2^16, in case uninited */ /* set breakpoint 6 here */
(gdb) record btrace
(gdb) b factorial
Breakpoint 2 at 0x40121b: file /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c, line 63.
(gdb) c
Continuing.
Breakpoint 2, factorial (value=6)
at /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c:63
63 if (value > 1) { /* set breakpoint 7 here */
(gdb) info record
Active record target: record-btrace
Recording format: Branch Trace Store.
Buffer size: 64kB.
Recorded 768 instructions in 22 functions (0 gaps) for thread 1 (process 19215).
(gdb) record function-call-history
13 do_lookup_x
14 _dl_lookup_symbol_x
15 _dl_fixup
16 _dl_runtime_resolve_xsavec
17 atoi
18 strtoq
19 ____strtoll_l_internal
20 atoi
21 main
22 factorial
(gdb) record instruction-history
759 0x00007ffff7ce0917 <____strtoll_l_internal+647>: pop %r15
760 0x00007ffff7ce0919 <____strtoll_l_internal+649>: retq
761 0x00007ffff7cdd064 <atoi+20>: add $0x8,%rsp
762 0x00007ffff7cdd068 <atoi+24>: retq
763 0x00000000004011b1 <main+75>: mov %eax,%edi
764 0x00000000004011b3 <main+77>: callq 0x401210 <factorial>
765 0x0000000000401210 <factorial+0>: push %rbp
766 0x0000000000401211 <factorial+1>: mov %rsp,%rbp
767 0x0000000000401214 <factorial+4>: sub $0x10,%rsp
768 0x0000000000401218 <factorial+8>: mov %edi,-0x4(%rbp)
AMD machine - Wrong behavior:
[kev@f32-1 gdb]$ ./gdb -q testsuite/outputs/gdb.base/break/break
Reading symbols from testsuite/outputs/gdb.base/break/break...
(gdb) start
Temporary breakpoint 1 at 0x401179: file /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c, line 43.
Starting program: /mesquite2/sourceware-git/f32-master/bld/gdb/testsuite/outputs/gdb.base/break/break
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffd5b8, envp=0x7fffffffd5c8)
at /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c:43
43 if (argc == 12345) { /* an unlikely value < 2^16, in case uninited */ /* set breakpoint 6 here */
(gdb) record btrace
(gdb) b factorial
Breakpoint 2 at 0x40121b: file /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c, line 63.
(gdb) c
Continuing.
Breakpoint 2, factorial (value=6)
at /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c:63
63 if (value > 1) { /* set breakpoint 7 here */
(gdb) info record
Active record target: record-btrace
Recording format: Branch Trace Store.
Buffer size: 64kB.
warning: Recorded trace may be incomplete at instruction 7737 (pc = 0x405000).
warning: Recorded trace may be incomplete at instruction 7739 (pc = 0x0).
Recorded 7740 instructions in 46 functions (2 gaps) for thread 1 (process 1402911).
(gdb) record function-call-history
37 ??
38 values
39 some_enum_global
40 ??
41 some_union_global
42 some_variable
43 ??
44 [decode error (2): unknown instruction]
45 ??
46 [decode error (2): unknown instruction]
(gdb) record instruction-history
7730 0x0000000000404ff3: add %al,(%rax)
7731 0x0000000000404ff5: add %al,(%rax)
7732 0x0000000000404ff7: add %al,(%rax)
7733 0x0000000000404ff9: add %al,(%rax)
7734 0x0000000000404ffb: add %al,(%rax)
7735 0x0000000000404ffd: add %al,(%rax)
7736 0x0000000000404fff: .byte 0x0
7737 0x0000000000405000: Cannot access memory at address 0x405000
Lastly, I'll note that I see a lot of gdb.btrace failures without
this commit. Worse still, the results aren't always the same which
causes a lot of noise when comparing test results.
gdbsupport/ChangeLog:
* btrace-common.h (btrace_cpu_vendor): Add CV_AMD.
gdb/ChangeLog:
* nat/linux-btrace.c (btrace_this_cpu): Add check for AMD
processors.
(cpu_supports_bts): Add CV_AMD case.
The updated pending stop series introduced a regression in Windows
debugging. When stopped at a software breakpoint, we would adjust the
PC each time it was requested -- however, more than a single
adjustment is incorrect. This patch introduces a new flag that is
used to ensure the adjustment only happens a single time.
No similar change is needed in gdbserver, because it adjusts the PC in
a different way.
I still can't run the gdb test suite on Windows, but I can run the
internal AdaCore test suite there; and this fixes the regressions
there.
gdb/ChangeLog
2020-04-24 Tom Tromey <tromey@adacore.com>
* nat/windows-nat.h (struct windows_thread_info)
<pc_adjusted>: New member.
* windows-nat.c (windows_fetch_one_register): Check
pc_adjusted.
(windows_nat_target::get_windows_debug_event)
(windows_nat_target::wait): Set pc_adjusted.
Simon pointed out that the windows-nat sharing series broke the Cygwin
build. This patch fixes the problem, by moving the Cygwin-specific
code to a new handler function. This approach is taken because this
code calls find_pc_partial_function, which isn't available in
gdbserver.
gdb/ChangeLog
2020-04-16 Tom Tromey <tromey@adacore.com>
* windows-nat.c (windows_nat::handle_access_violation): New
function.
* nat/windows-nat.h (handle_access_violation): Declare.
* nat/windows-nat.c (handle_exception): Move Cygwin code to
windows-nat.c. Call handle_access_violation.
gdbserver/ChangeLog
2020-04-16 Tom Tromey <tromey@adacore.com>
* win32-low.cc (windows_nat::handle_access_violation): New
function.
