4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
commit c5d343b6b7badd1f5fe0873eff2e8d63a193e732 upstream.
In Documentation/trace/kprobetrace.txt, it says
@SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867af ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.
This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.
Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace_kprobe.c | 4 ++--
kernel/trace/trace_probe.c | 8 +++-----
kernel/trace/trace_probe.h | 2 +-
3 files changed, 6 insertions(+), 8 deletions(-)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -607,7 +607,7 @@ static int create_trace_kprobe(int argc,
bool is_return = false, is_delete = false;
char *symbol = NULL, *event = NULL, *group = NULL;
char *arg;
- unsigned long offset = 0;
+ long offset = 0;
void *addr = NULL;
char buf[MAX_EVENT_NAME_LEN];
@@ -675,7 +675,7 @@ static int create_trace_kprobe(int argc,
symbol = argv[1];
/* TODO: support .init module functions */
ret = traceprobe_split_symbol_offset(symbol, &offset);
- if (ret) {
+ if (ret || offset < 0 || offset > UINT_MAX) {
pr_info("Failed to parse either an address or a symbol.\n");
return ret;
}
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -319,7 +319,7 @@ static fetch_func_t get_fetch_size_funct
}
/* Split symbol and offset. */
-int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset)
+int traceprobe_split_symbol_offset(char *symbol, long *offset)
{
char *tmp;
int ret;
@@ -327,13 +327,11 @@ int traceprobe_split_symbol_offset(char
if (!offset)
return -EINVAL;
- tmp = strchr(symbol, '+');
+ tmp = strpbrk(symbol, "+-");
if (tmp) {
- /* skip sign because kstrtoul doesn't accept '+' */
- ret = kstrtoul(tmp + 1, 0, offset);
+ ret = kstrtol(tmp, 0, offset);
if (ret)
return ret;
-
*tmp = '\0';
} else
*offset = 0;
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -354,7 +354,7 @@ extern int traceprobe_conflict_field_nam
extern void traceprobe_update_arg(struct probe_arg *arg);
extern void traceprobe_free_probe_arg(struct probe_arg *arg);
-extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
+extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
extern ssize_t traceprobe_probes_write(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos,