[DTrace-devel] [PATCH v2 3/3] Add support for copyoutstr() subroutine
Kris Van Hees
kris.van.hees at oracle.com
Fri Feb 24 00:50:43 UTC 2023
Reviewed-by: Kris Van Hees <kris.van.hees at oracle.com>
On Mon, Feb 06, 2023 at 04:10:04PM -0500, eugene.loh--- via DTrace-devel wrote:
> From: Eugene Loh <eugene.loh at oracle.com>
>
> Move tests to their own copyoutstr/ subdirectory to mimic other copy*
> tests.
>
> Signed-off-by: Eugene Loh <eugene.loh at oracle.com>
> ---
> libdtrace/dt_cg.c | 75 ++++++++++++++++++-
> .../err.D_PROTO_LEN.copyoutstrbadarg.d | 0
> .../err.D_PROTO_LEN.copyoutstrbadarg.r | 2 +
> .../err.D_PROTO_LEN.copyoutstrtoofew.d | 0
> .../err.D_PROTO_LEN.copyoutstrtoofew.r | 2 +
> .../err.copyoutstrbadaddr.aarch64.x | 0
> .../{ => copyoutstr}/err.copyoutstrbadaddr.sh | 0
> .../funcs/copyoutstr/tst.copyoutstr.r | 6 ++
> .../funcs/copyoutstr/tst.copyoutstr.sh | 73 ++++++++++++++++++
> .../funcs/err.D_PROTO_LEN.copyoutstrbadarg.r | 2 -
> .../funcs/err.D_PROTO_LEN.copyoutstrtoofew.r | 2 -
> .../err.D_ACT_SPEC.SpeculateWithCopyOutStr.d | 4 +-
> 12 files changed, 159 insertions(+), 7 deletions(-)
> rename test/unittest/funcs/{ => copyoutstr}/err.D_PROTO_LEN.copyoutstrbadarg.d (100%)
> create mode 100644 test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.r
> rename test/unittest/funcs/{ => copyoutstr}/err.D_PROTO_LEN.copyoutstrtoofew.d (100%)
> create mode 100644 test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.r
> rename test/unittest/funcs/{ => copyoutstr}/err.copyoutstrbadaddr.aarch64.x (100%)
> rename test/unittest/funcs/{ => copyoutstr}/err.copyoutstrbadaddr.sh (100%)
> create mode 100644 test/unittest/funcs/copyoutstr/tst.copyoutstr.r
> create mode 100755 test/unittest/funcs/copyoutstr/tst.copyoutstr.sh
> delete mode 100644 test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.r
> delete mode 100644 test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.r
>
> diff --git a/libdtrace/dt_cg.c b/libdtrace/dt_cg.c
> index 44209a05..c2eb85c0 100644
> --- a/libdtrace/dt_cg.c
> +++ b/libdtrace/dt_cg.c
> @@ -4755,6 +4755,79 @@ dt_cg_subr_copyout(dt_node_t *dnp, dt_irlist_t *dlp, dt_regset_t *drp)
> TRACE_REGSET(" subr-copyout:End ");
> }
>
> +static void
> +dt_cg_subr_copyoutstr(dt_node_t *dnp, dt_irlist_t *dlp, dt_regset_t *drp)
> +{
> + dt_node_t *src = dnp->dn_args;
> + dt_node_t *dst = src->dn_list;
> + dt_node_t *size = dst->dn_list;
> + size_t strsize = yypcb->pcb_hdl->dt_options[DTRACEOPT_STRSIZE];
> + uint64_t off;
> + uint_t L1 = dt_irlist_label(dlp);
> + uint_t L2 = dt_irlist_label(dlp);
> + uint_t L3 = dt_irlist_label(dlp);
> +
> + dt_cg_clsflags(yypcb, DTRACEACT_PROC_DESTRUCTIVE, dnp);
> +
> + TRACE_REGSET(" subr-copyoutstr:Begin");
> +
> + dt_cg_node(src, dlp, drp);
> + dt_cg_node(dst, dlp, drp);
> + dt_cg_node(size, dlp, drp);
> +
> + /* if (size > strsize) size = strsize */
> + emit(dlp, BPF_BRANCH_IMM(BPF_JLE, size->dn_reg, strsize, L1));
> + emit(dlp, BPF_MOV_IMM(size->dn_reg, strsize));
> + emitl(dlp, L1,
> + BPF_NOP());
> +
> + /* validate the pointers */
> + dt_cg_check_ptr_arg(dlp, drp, src, size);
> + dt_cg_check_notnull(dlp, drp, dst->dn_reg);
> +
> + /* copy into a temporary string to determine the string length */
> + if (dt_regset_xalloc_args(drp) == -1)
> + longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);
> + emit(dlp, BPF_MOV_REG(BPF_REG_2, size->dn_reg));
> + dt_regset_free(drp, size->dn_reg);
> + emit(dlp, BPF_MOV_REG(BPF_REG_3, src->dn_reg));
> + off = dt_cg_tstring_xalloc(yypcb);
> + emit(dlp, BPF_LOAD(BPF_DW, BPF_REG_1, BPF_REG_FP, DT_STK_DCTX));
> + emit(dlp, BPF_LOAD(BPF_DW, BPF_REG_1, BPF_REG_1, DCTX_MEM));
> + emit(dlp, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, off));
> + dt_regset_xalloc(drp, BPF_REG_0);
> + emit(dlp, BPF_CALL_HELPER(BPF_FUNC_probe_read_str));
> + dt_regset_free_args(drp);
> + dt_cg_tstring_xfree(yypcb, off);
> +
> + /* check that we could read the string */
> + emit(dlp, BPF_BRANCH_IMM(BPF_JSGT, BPF_REG_0, 0, L2));
> + dt_cg_probe_error(yypcb, DTRACEFLT_BADADDR, DT_ISREG, src->dn_reg); // FIXME: is this right?
> + emitl(dlp, L2,
> + BPF_NOP());
> +
> + /* copy with the measured size */
> + if (dt_regset_xalloc_args(drp) == -1)
> + longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);
> + emit(dlp, BPF_MOV_REG(BPF_REG_1, dst->dn_reg));
> + emit(dlp, BPF_MOV_REG(BPF_REG_2, src->dn_reg));
> + emit(dlp, BPF_MOV_REG(BPF_REG_3, BPF_REG_0));
> + emit(dlp, BPF_CALL_HELPER(BPF_FUNC_probe_write_user));
> + dt_regset_free_args(drp);
> +
> + /* since src was validated, any problem must be with dst */
> + emit(dlp, BPF_BRANCH_IMM(BPF_JEQ, BPF_REG_0, 0, L3));
> + dt_regset_free(drp, BPF_REG_0);
> + dt_cg_probe_error(yypcb, DTRACEFLT_BADADDR, DT_ISREG, dst->dn_reg);
> + emitl(dlp, L3,
> + BPF_NOP());
> +
> + dt_regset_free(drp, src->dn_reg);
> + dt_regset_free(drp, dst->dn_reg);
> +
> + TRACE_REGSET(" subr-copyoutstr:End ");
> +}
> +
> static void
> dt_cg_subr_strchr(dt_node_t *dnp, dt_irlist_t *dlp, dt_regset_t *drp)
> {
> @@ -5232,7 +5305,7 @@ static dt_cg_subr_f *_dt_cg_subr[DIF_SUBR_MAX + 1] = {
> [DIF_SUBR_PROGENYOF] = &dt_cg_subr_progenyof,
> [DIF_SUBR_STRLEN] = &dt_cg_subr_strlen,
> [DIF_SUBR_COPYOUT] = &dt_cg_subr_copyout,
> - [DIF_SUBR_COPYOUTSTR] = NULL,
> + [DIF_SUBR_COPYOUTSTR] = &dt_cg_subr_copyoutstr,
> [DIF_SUBR_ALLOCA] = &dt_cg_subr_alloca,
> [DIF_SUBR_BCOPY] = &dt_cg_subr_bcopy,
> [DIF_SUBR_COPYINTO] = &dt_cg_subr_copyinto,
> diff --git a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.d b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.d
> similarity index 100%
> rename from test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.d
> rename to test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.d
> diff --git a/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.r b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.r
> new file mode 100644
> index 00000000..6b36f9bf
> --- /dev/null
> +++ b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.r
> @@ -0,0 +1,2 @@
> +-- @@stderr --
> +dtrace: failed to compile script test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrbadarg.d: [D_PROTO_LEN] line 19: copyoutstr( ) prototype mismatch: 2 args passed, 3 expected
> diff --git a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.d b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.d
> similarity index 100%
> rename from test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.d
> rename to test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.d
> diff --git a/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.r b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.r
> new file mode 100644
> index 00000000..7b205988
> --- /dev/null
> +++ b/test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.r
> @@ -0,0 +1,2 @@
> +-- @@stderr --
> +dtrace: failed to compile script test/unittest/funcs/copyoutstr/err.D_PROTO_LEN.copyoutstrtoofew.d: [D_PROTO_LEN] line 19: copyoutstr( ) prototype mismatch: 1 arg passed, 3 expected
> diff --git a/test/unittest/funcs/err.copyoutstrbadaddr.aarch64.x b/test/unittest/funcs/copyoutstr/err.copyoutstrbadaddr.aarch64.x
> similarity index 100%
> rename from test/unittest/funcs/err.copyoutstrbadaddr.aarch64.x
> rename to test/unittest/funcs/copyoutstr/err.copyoutstrbadaddr.aarch64.x
> diff --git a/test/unittest/funcs/err.copyoutstrbadaddr.sh b/test/unittest/funcs/copyoutstr/err.copyoutstrbadaddr.sh
> similarity index 100%
> rename from test/unittest/funcs/err.copyoutstrbadaddr.sh
> rename to test/unittest/funcs/copyoutstr/err.copyoutstrbadaddr.sh
> diff --git a/test/unittest/funcs/copyoutstr/tst.copyoutstr.r b/test/unittest/funcs/copyoutstr/tst.copyoutstr.r
> new file mode 100644
> index 00000000..ac474fec
> --- /dev/null
> +++ b/test/unittest/funcs/copyoutstr/tst.copyoutstr.r
> @@ -0,0 +1,6 @@
> +size is longer than the string; expect full string with terminating byte
> +HELLO WORLD; YOU HAVE A LONG MESSAGE TO DELIVER|---------------
> +
> +size is shorter than the string; expect 32 chars without terminating byte
> +HELLO WORLD; YOU HAVE A LONG MES-------------------------------
> +
> diff --git a/test/unittest/funcs/copyoutstr/tst.copyoutstr.sh b/test/unittest/funcs/copyoutstr/tst.copyoutstr.sh
> new file mode 100755
> index 00000000..d98897fc
> --- /dev/null
> +++ b/test/unittest/funcs/copyoutstr/tst.copyoutstr.sh
> @@ -0,0 +1,73 @@
> +#!/bin/bash
> +#
> +# Oracle Linux DTrace.
> +# Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
> +# Licensed under the Universal Permissive License v 1.0 as shown at
> +# http://oss.oracle.com/licenses/upl.
> +
> +dtrace=$1
> +DIRNAME="$tmpdir/copyoutstr.$$.$RANDOM"
> +mkdir -p $DIRNAME
> +cd $DIRNAME
> +
> +# Construct a C program that:
> +# - initializes a user buffer
> +# - passes that buffer to a syscall (where DTrace will overwrite the buffer)
> +# - checks the buffer
> +cat << EOF > main.c
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <stdio.h>
> +#include <string.h>
> +int main(int c, char **v) {
> + int i, fd = open("/dev/null", O_WRONLY);
> + char s[64];
> +
> + /* initialize buffer */
> + memset(s, '-', sizeof(s));
> + s[sizeof(s) - 1] = '\0';
> +
> + /* write buffer to /dev/null (the D script will overwrite s) */
> + write(fd, s, strlen(s));
> + close(fd);
> +
> + /* turn NUL chars (except last one) into printable '|' */
> + for (i = 0; i < sizeof(s) - 1; i++)
> + if (s[i] == '\0')
> + s[i] = '|';
> +
> + /* print buffer contents */
> + printf("%s\n", s);
> + return 0;
> +}
> +EOF
> +
> +gcc main.c
> +if [ $? -ne 0 ]; then
> + echo "compilation error"
> + exit 1
> +fi
> +
> +# $1 is copyoutstr() size
> +# $2 is DTrace options
> +# $3 is description of test
> +function mytest() {
> + echo $3
> + $dtrace $dt_flags $2 -qwn '
> + syscall::write:entry
> + /pid == $target/
> + {
> + s = "HELLO WORLD; YOU HAVE A LONG MESSAGE TO DELIVER";
> + copyoutstr(s, arg1, '$1');
> + exit(0);
> + }' -c ./a.out
> + if [ $? -ne 0 ]; then
> + echo "DTrace error"
> + exit 1
> + fi
> +}
> +
> +mytest 64 " " "size is longer than the string; expect full string with terminating byte"
> +mytest 32 " " "size is shorter than the string; expect 32 chars without terminating byte"
> +
> +exit 0
> diff --git a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.r b/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.r
> deleted file mode 100644
> index f13ac2ed..00000000
> --- a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.r
> +++ /dev/null
> @@ -1,2 +0,0 @@
> --- @@stderr --
> -dtrace: failed to compile script test/unittest/funcs/err.D_PROTO_LEN.copyoutstrbadarg.d: [D_PROTO_LEN] line 19: copyoutstr( ) prototype mismatch: 2 args passed, 3 expected
> diff --git a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.r b/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.r
> deleted file mode 100644
> index fce3d846..00000000
> --- a/test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.r
> +++ /dev/null
> @@ -1,2 +0,0 @@
> --- @@stderr --
> -dtrace: failed to compile script test/unittest/funcs/err.D_PROTO_LEN.copyoutstrtoofew.d: [D_PROTO_LEN] line 19: copyoutstr( ) prototype mismatch: 1 arg passed, 3 expected
> diff --git a/test/unittest/speculation/err.D_ACT_SPEC.SpeculateWithCopyOutStr.d b/test/unittest/speculation/err.D_ACT_SPEC.SpeculateWithCopyOutStr.d
> index 1b23ec3b..43a41440 100644
> --- a/test/unittest/speculation/err.D_ACT_SPEC.SpeculateWithCopyOutStr.d
> +++ b/test/unittest/speculation/err.D_ACT_SPEC.SpeculateWithCopyOutStr.d
> @@ -1,11 +1,11 @@
> #!/usr/sbin/dtrace -ws
> /*
> * Oracle Linux DTrace.
> - * Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
> + * Copyright (c) 2006, 2023, Oracle and/or its affiliates. All rights reserved.
> * Licensed under the Universal Permissive License v 1.0 as shown at
> * http://oss.oracle.com/licenses/upl.
> */
> -/* @@skip: dtv2, no copyoutstr yet */
> +
> /*
> * ASSERTION: Destructive actions may never be speculative.
> *
> --
> 2.18.4
>
>
> _______________________________________________
> DTrace-devel mailing list
> DTrace-devel at oss.oracle.com
> https://oss.oracle.com/mailman/listinfo/dtrace-devel
More information about the DTrace-devel
mailing list