Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull kprobe fixes from Steven Rostedt:
"The documentation for kprobe events says that symbol offets can take
both a + and - sign to get to befor and after the symbol address.
But in actuality, the code does not support the minus. This fixes that
issue, and adds a few more selftests to kprobe events"
* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests: ftrace: Add a testcase for probepoint
selftests: ftrace: Add a testcase for string type with kprobe_event
selftests: ftrace: Add probe event argument syntax testcase
tracing: probeevent: Fix to support minus offset from symbol
+192
-8
+2
-2
kernel/trace/trace_kprobe.c
+2
-2
kernel/trace/trace_kprobe.c
···
659
659
char *symbol = NULL, *event = NULL, *group = NULL;
660
660
int maxactive = 0;
661
661
char *arg;
662
-
unsigned long offset = 0;
662
+
long offset = 0;
663
663
void *addr = NULL;
664
664
char buf[MAX_EVENT_NAME_LEN];
665
665
···
747
747
symbol = argv[1];
748
748
/* TODO: support .init module functions */
749
749
ret = traceprobe_split_symbol_offset(symbol, &offset);
750
-
if (ret) {
750
+
if (ret || offset < 0 || offset > UINT_MAX) {
751
751
pr_info("Failed to parse either an address or a symbol.\n");
752
752
return ret;
753
753
}
+3
-5
kernel/trace/trace_probe.c
+3
-5
kernel/trace/trace_probe.c
···
320
320
}
321
321
322
322
/* Split symbol and offset. */
323
-
int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset)
323
+
int traceprobe_split_symbol_offset(char *symbol, long *offset)
324
324
{
325
325
char *tmp;
326
326
int ret;
···
328
328
if (!offset)
329
329
return -EINVAL;
330
330
331
-
tmp = strchr(symbol, '+');
331
+
tmp = strpbrk(symbol, "+-");
332
332
if (tmp) {
333
-
/* skip sign because kstrtoul doesn't accept '+' */
334
-
ret = kstrtoul(tmp + 1, 0, offset);
333
+
ret = kstrtol(tmp, 0, offset);
335
334
if (ret)
336
335
return ret;
337
-
338
336
*tmp = '\0';
339
337
} else
340
338
*offset = 0;
+1
-1
kernel/trace/trace_probe.h
+1
-1
kernel/trace/trace_probe.h
···
365
365
extern void traceprobe_update_arg(struct probe_arg *arg);
366
366
extern void traceprobe_free_probe_arg(struct probe_arg *arg);
367
367
368
-
extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
368
+
extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
369
369
370
370
/* Sum up total data length for dynamic arraies (strings) */
371
371
static nokprobe_inline int
+46
tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
+46
tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_string.tc
···
1
+
#!/bin/sh
2
+
# SPDX-License-Identifier: GPL-2.0
3
+
# description: Kprobe event string type argument
4
+
5
+
[ -f kprobe_events ] || exit_unsupported # this is configurable
6
+
7
+
echo 0 > events/enable
8
+
echo > kprobe_events
9
+
10
+
case `uname -m` in
11
+
x86_64)
12
+
ARG2=%si
13
+
OFFS=8
14
+
;;
15
+
i[3456]86)
16
+
ARG2=%cx
17
+
OFFS=4
18
+
;;
19
+
aarch64)
20
+
ARG2=%x1
21
+
OFFS=8
22
+
;;
23
+
arm*)
24
+
ARG2=%r1
25
+
OFFS=4
26
+
;;
27
+
*)
28
+
echo "Please implement other architecture here"
29
+
exit_untested
30
+
esac
31
+
32
+
: "Test get argument (1)"
33
+
echo "p:testprobe create_trace_kprobe arg1=+0(+0(${ARG2})):string" > kprobe_events
34
+
echo 1 > events/kprobes/testprobe/enable
35
+
! echo test >> kprobe_events
36
+
tail -n 1 trace | grep -qe "testprobe.* arg1=\"test\""
37
+
38
+
echo 0 > events/kprobes/testprobe/enable
39
+
: "Test get argument (2)"
40
+
echo "p:testprobe create_trace_kprobe arg1=+0(+0(${ARG2})):string arg2=+0(+${OFFS}(${ARG2})):string" > kprobe_events
41
+
echo 1 > events/kprobes/testprobe/enable
42
+
! echo test1 test2 >> kprobe_events
43
+
tail -n 1 trace | grep -qe "testprobe.* arg1=\"test1\" arg2=\"test2\""
44
+
45
+
echo 0 > events/enable
46
+
echo > kprobe_events
+97
tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc
+97
tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_syntax.tc
···
1
+
#!/bin/sh
2
+
# SPDX-License-Identifier: GPL-2.0
3
+
# description: Kprobe event argument syntax
4
+
5
+
[ -f kprobe_events ] || exit_unsupported # this is configurable
6
+
7
+
grep "x8/16/32/64" README > /dev/null || exit_unsupported # version issue
8
+
9
+
echo 0 > events/enable
10
+
echo > kprobe_events
11
+
12
+
PROBEFUNC="vfs_read"
13
+
GOODREG=
14
+
BADREG=
15
+
GOODSYM="_sdata"
16
+
if ! grep -qw ${GOODSYM} /proc/kallsyms ; then
17
+
GOODSYM=$PROBEFUNC
18
+
fi
19
+
BADSYM="deaqswdefr"
20
+
SYMADDR=0x`grep -w ${GOODSYM} /proc/kallsyms | cut -f 1 -d " "`
21
+
GOODTYPE="x16"
22
+
BADTYPE="y16"
23
+
24
+
case `uname -m` in
25
+
x86_64|i[3456]86)
26
+
GOODREG=%ax
27
+
BADREG=%ex
28
+
;;
29
+
aarch64)
30
+
GOODREG=%x0
31
+
BADREG=%ax
32
+
;;
33
+
arm*)
34
+
GOODREG=%r0
35
+
BADREG=%ax
36
+
;;
37
+
esac
38
+
39
+
test_goodarg() # Good-args
40
+
{
41
+
while [ "$1" ]; do
42
+
echo "p ${PROBEFUNC} $1" > kprobe_events
43
+
shift 1
44
+
done;
45
+
}
46
+
47
+
test_badarg() # Bad-args
48
+
{
49
+
while [ "$1" ]; do
50
+
! echo "p ${PROBEFUNC} $1" > kprobe_events
51
+
shift 1
52
+
done;
53
+
}
54
+
55
+
echo > kprobe_events
56
+
57
+
: "Register access"
58
+
test_goodarg ${GOODREG}
59
+
test_badarg ${BADREG}
60
+
61
+
: "Symbol access"
62
+
test_goodarg "@${GOODSYM}" "@${SYMADDR}" "@${GOODSYM}+10" "@${GOODSYM}-10"
63
+
test_badarg "@" "@${BADSYM}" "@${GOODSYM}*10" "@${GOODSYM}/10" \
64
+
"@${GOODSYM}%10" "@${GOODSYM}&10" "@${GOODSYM}|10"
65
+
66
+
: "Stack access"
67
+
test_goodarg "\$stack" "\$stack0" "\$stack1"
68
+
test_badarg "\$stackp" "\$stack0+10" "\$stack1-10"
69
+
70
+
: "Retval access"
71
+
echo "r ${PROBEFUNC} \$retval" > kprobe_events
72
+
! echo "p ${PROBEFUNC} \$retval" > kprobe_events
73
+
74
+
: "Comm access"
75
+
test_goodarg "\$comm"
76
+
77
+
: "Indirect memory access"
78
+
test_goodarg "+0(${GOODREG})" "-0(${GOODREG})" "+10(\$stack)" \
79
+
"+0(\$stack1)" "+10(@${GOODSYM}-10)" "+0(+10(+20(\$stack)))"
80
+
test_badarg "+(${GOODREG})" "(${GOODREG}+10)" "-(${GOODREG})" "(${GOODREG})" \
81
+
"+10(\$comm)" "+0(${GOODREG})+10"
82
+
83
+
: "Name assignment"
84
+
test_goodarg "varname=${GOODREG}"
85
+
test_badarg "varname=varname2=${GOODREG}"
86
+
87
+
: "Type syntax"
88
+
test_goodarg "${GOODREG}:${GOODTYPE}"
89
+
test_badarg "${GOODREG}::${GOODTYPE}" "${GOODREG}:${BADTYPE}" \
90
+
"${GOODTYPE}:${GOODREG}"
91
+
92
+
: "Combination check"
93
+
94
+
test_goodarg "\$comm:string" "+0(\$stack):string"
95
+
test_badarg "\$comm:x64" "\$stack:string" "${GOODREG}:string"
96
+
97
+
echo > kprobe_events
+43
tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc
+43
tools/testing/selftests/ftrace/test.d/kprobe/probepoint.tc
···
1
+
#!/bin/sh
2
+
# SPDX-License-Identifier: GPL-2.0
3
+
# description: Kprobe events - probe points
4
+
5
+
[ -f kprobe_events ] || exit_unsupported # this is configurable
6
+
7
+
TARGET_FUNC=create_trace_kprobe
8
+
9
+
dec_addr() { # hexaddr
10
+
printf "%d" "0x"`echo $1 | tail -c 8`
11
+
}
12
+
13
+
set_offs() { # prev target next
14
+
A1=`dec_addr $1`
15
+
A2=`dec_addr $2`
16
+
A3=`dec_addr $3`
17
+
TARGET="0x$2" # an address
18
+
PREV=`expr $A1 - $A2` # offset to previous symbol
19
+
NEXT=+`expr $A3 - $A2` # offset to next symbol
20
+
OVERFLOW=+`printf "0x%x" ${PREV}` # overflow offset to previous symbol
21
+
}
22
+
23
+
# We have to decode symbol addresses to get correct offsets.
24
+
# If the offset is not an instruction boundary, it cause -EILSEQ.
25
+
set_offs `grep -A1 -B1 ${TARGET_FUNC} /proc/kallsyms | cut -f 1 -d " " | xargs`
26
+
27
+
UINT_TEST=no
28
+
# printf "%x" -1 returns (unsigned long)-1.
29
+
if [ `printf "%x" -1 | wc -c` != 9 ]; then
30
+
UINT_TEST=yes
31
+
fi
32
+
33
+
echo 0 > events/enable
34
+
echo > kprobe_events
35
+
echo "p:testprobe ${TARGET_FUNC}" > kprobe_events
36
+
echo "p:testprobe ${TARGET}" > kprobe_events
37
+
echo "p:testprobe ${TARGET_FUNC}${NEXT}" > kprobe_events
38
+
! echo "p:testprobe ${TARGET_FUNC}${PREV}" > kprobe_events
39
+
if [ "${UINT_TEST}" = yes ]; then
40
+
! echo "p:testprobe ${TARGET_FUNC}${OVERFLOW}" > kprobe_events
41
+
fi
42
+
echo > kprobe_events
43
+
clear_trace