Re: [PATCH][gdb/testsuite] Support recording of getrandom

[Tom de Vries <tdevries@suse.de>]

On 6/27/22 13:08, Tom de Vries wrote:
> Hi,
> 
> Add missing support for recording of linux syscall getrandom.
> 
> Tested on x86_64-linux with native and target board unix/-m32.
> 
> Any comments?
> 

FWIW, I ran this through the try-buildbot, and it came back clean.

Thanks,
- Tom

> [gdb/testsuite] Support recording of getrandom
> 
> ---
>   gdb/aarch64-linux-tdep.c                |  2 ++
>   gdb/amd64-linux-tdep.c                  |  3 ++
>   gdb/amd64-linux-tdep.h                  |  3 +-
>   gdb/arm-linux-tdep.c                    |  1 +
>   gdb/linux-record.c                      |  6 ++++
>   gdb/linux-record.h                      |  1 +
>   gdb/ppc-linux-tdep.c                    |  2 ++
>   gdb/s390-linux-tdep.c                   |  2 ++
>   gdb/testsuite/gdb.reverse/getrandom.c   | 41 ++++++++++++++++++++++++
>   gdb/testsuite/gdb.reverse/getrandom.exp | 56 +++++++++++++++++++++++++++++++++
>   10 files changed, 116 insertions(+), 1 deletion(-)
> 
> diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c
> index 453692df2f4..5ed73532637 100644
> --- a/gdb/aarch64-linux-tdep.c
> +++ b/gdb/aarch64-linux-tdep.c
> @@ -1159,6 +1159,7 @@ enum aarch64_syscall {
>     aarch64_sys_finit_module = 273,
>     aarch64_sys_sched_setattr = 274,
>     aarch64_sys_sched_getattr = 275,
> +  aarch64_sys_getrandom = 278
>   };
>   
>   /* aarch64_canonicalize_syscall maps syscall ids from the native AArch64
> @@ -1441,6 +1442,7 @@ aarch64_canonicalize_syscall (enum aarch64_syscall syscall_number)
>         UNSUPPORTED_SYSCALL_MAP (finit_module);
>         UNSUPPORTED_SYSCALL_MAP (sched_setattr);
>         UNSUPPORTED_SYSCALL_MAP (sched_getattr);
> +      SYSCALL_MAP (getrandom);
>     default:
>       return gdb_sys_no_syscall;
>     }
> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
> index 9a0759d639c..18a0c3f3941 100644
> --- a/gdb/amd64-linux-tdep.c
> +++ b/gdb/amd64-linux-tdep.c
> @@ -463,6 +463,9 @@ amd64_canonicalize_syscall (enum amd64_syscall syscall_number)
>     case amd64_sys_pipe2:
>       return gdb_sys_pipe2;
>   
> +  case amd64_sys_getrandom:
> +    return gdb_sys_getrandom;
> +
>     case amd64_sys_select:
>     case amd64_x32_sys_select:
>       return gdb_sys_select;
> diff --git a/gdb/amd64-linux-tdep.h b/gdb/amd64-linux-tdep.h
> index 184b0c86f07..ef111f4ac2a 100644
> --- a/gdb/amd64-linux-tdep.h
> +++ b/gdb/amd64-linux-tdep.h
> @@ -320,7 +320,8 @@ enum amd64_syscall {
>     amd64_sys_sync_file_range = 277,
>     amd64_sys_vmsplice = 278,
>     amd64_sys_move_pages = 279,
> -  amd64_sys_pipe2 = 293
> +  amd64_sys_pipe2 = 293,
> +  amd64_sys_getrandom = 318
>   };
>   
>   /* Enum that defines the syscall identifiers for x32 linux.
> diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c
> index f299e9665d5..33406f90b15 100644
> --- a/gdb/arm-linux-tdep.c
> +++ b/gdb/arm-linux-tdep.c
> @@ -1610,6 +1610,7 @@ arm_canonicalize_syscall (int syscall)
>       case 378: return gdb_sys_kcmp;
>       case 379: return gdb_sys_finit_module;
>         */
> +    case 384: return gdb_sys_getrandom;
>       case 983041: /* ARM_breakpoint */ return gdb_sys_no_syscall;
>       case 983042: /* ARM_cacheflush */ return gdb_sys_no_syscall;
>       case 983043: /* ARM_usr26 */ return gdb_sys_no_syscall;
> diff --git a/gdb/linux-record.c b/gdb/linux-record.c
> index 1e8e3c95567..a500bc915aa 100644
> --- a/gdb/linux-record.c
> +++ b/gdb/linux-record.c
> @@ -356,6 +356,12 @@ record_linux_system_call (enum gdb_syscall syscall,
>   	return -1;
>         break;
>   
> +    case gdb_sys_getrandom:
> +      regcache_raw_read_unsigned (regcache, tdep->arg2, &tmpulongest);
> +      if (record_mem_at_reg (regcache, tdep->arg1, tmpulongest))
> +	return -1;
> +      break;
> +
>       case gdb_sys_times:
>         if (record_mem_at_reg (regcache, tdep->arg1, tdep->size_tms))
>   	return -1;
> diff --git a/gdb/linux-record.h b/gdb/linux-record.h
> index 39d7d4b54d0..56c111cf6b6 100644
> --- a/gdb/linux-record.h
> +++ b/gdb/linux-record.h
> @@ -510,6 +510,7 @@ enum gdb_syscall {
>     gdb_sys_dup3 = 330,
>     gdb_sys_pipe2 = 331,
>     gdb_sys_inotify_init1 = 332,
> +  gdb_sys_getrandom = 355,
>     gdb_sys_statx = 383,
>     gdb_sys_socket = 500,
>     gdb_sys_connect = 501,
> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
> index bf95f395515..2f28337bde0 100644
> --- a/gdb/ppc-linux-tdep.c
> +++ b/gdb/ppc-linux-tdep.c
> @@ -1406,6 +1406,8 @@ ppc_canonicalize_syscall (int syscall, int wordsize)
>       result = gdb_sys_recvfrom;
>     else if (syscall == 342)
>       result = gdb_sys_recvmsg;
> +  else if (syscall == 359)
> +    result = gdb_sys_getrandom;
>   
>     return (enum gdb_syscall) result;
>   }
> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
> index 9d4e2d09f2a..5be4984fb57 100644
> --- a/gdb/s390-linux-tdep.c
> +++ b/gdb/s390-linux-tdep.c
> @@ -787,6 +787,8 @@ s390_canonicalize_syscall (int syscall, enum s390_abi_kind abi)
>   	/* ioprio_set .. epoll_pwait */
>   	else if (syscall >= 282 && syscall <= 312)
>   	  ret = syscall + 7;
> +	else if (syscall == 349)
> +	  ret = gdb_sys_getrandom;
>   	else
>   	  ret = gdb_sys_no_syscall;
>   
> diff --git a/gdb/testsuite/gdb.reverse/getrandom.c b/gdb/testsuite/gdb.reverse/getrandom.c
> new file mode 100644
> index 00000000000..162de6ed81b
> --- /dev/null
> +++ b/gdb/testsuite/gdb.reverse/getrandom.c
> @@ -0,0 +1,41 @@
> +/* This testcase is part of GDB, the GNU debugger.
> +
> +   Copyright 2022 Free Software Foundation, Inc.
> +
> +   This program is free software; you can redistribute it and/or modify
> +   it under the terms of the GNU General Public License as published by
> +   the Free Software Foundation; either version 3 of the License, or
> +   (at your option) any later version.
> +
> +   This program is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +   GNU General Public License for more details.
> +
> +   You should have received a copy of the GNU General Public License
> +   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
> +
> +#include <sys/random.h>
> +
> +void
> +marker1 (void)
> +{
> +}
> +
> +void
> +marker2 (void)
> +{
> +}
> +
> +unsigned char buf[6];
> +
> +int
> +main (void)
> +{
> +  buf[0] = 0xff;
> +  buf[5] = 0xff;
> +  marker1 ();
> +  volatile ssize_t r = getrandom (&buf[1], 4, 0);
> +  marker2 ();
> +  return 0;
> +}
> diff --git a/gdb/testsuite/gdb.reverse/getrandom.exp b/gdb/testsuite/gdb.reverse/getrandom.exp
> new file mode 100644
> index 00000000000..b1c7d9dad80
> --- /dev/null
> +++ b/gdb/testsuite/gdb.reverse/getrandom.exp
> @@ -0,0 +1,56 @@
> +# Copyright 2022 Free Software Foundation, Inc.
> +
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +
> +# This file is part of the gdb testsuite.
> +
> +#
> +# This test tests getrandom syscall for reverse execution.
> +#
> +
> +if ![supports_reverse] {
> +    return
> +}
> +
> +standard_testfile
> +
> +if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
> +    return -1
> +}
> +
> +runto_main
> +
> +if [supports_process_record] {
> +    # Activate process record/replay
> +    gdb_test_no_output "record" "turn on process record"
> +}
> +
> +gdb_test "break marker2" \
> +    "Breakpoint $decimal at $hex: file .*$srcfile, line $decimal.*" \
> +    "set breakpoint at marker2"
> +
> +gdb_continue_to_breakpoint "marker2" ".*$srcfile:.*"
> +
> +gdb_test "break marker1" \
> +    "Breakpoint $decimal at $hex: file .*$srcfile, line $decimal.*" \
> +    "set breakpoint at marker1"
> +
> +gdb_test "reverse-continue" ".*$srcfile:$decimal.*" "reverse to marker1"
> +
> +gdb_test "print (unsigned)buf\[0\]" ".* = 255" "check buf\[0\]"
> +gdb_test "print (unsigned)buf\[1\]" ".* = 0" "check buf\[1\]"
> +gdb_test "print (unsigned)buf\[2\]" ".* = 0" "check buf\[2\]"
> +gdb_test "print (unsigned)buf\[3\]" ".* = 0" "check buf\[3\]"
> +gdb_test "print (unsigned)buf\[4\]" ".* = 0" "check buf\[4\]"
> +gdb_test "print (unsigned)buf\[5\]" ".* = 255" "check buf\[5\]"