| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20231130234048.157509-14-lb@semihalf.com>
Date: Fri, 1 Dec 2023 00:40:46 +0100
From: Łukasz Bartosik <lb@...ihalf.com>
To: Jason Baron <jbaron@...mai.com>, Jim Cromie <jim.cromie@...il.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Kees Cook <keescook@...omium.org>,
Douglas Anderson <dianders@...omium.org>
Cc: Guenter Roeck <groeck@...gle.com>,
Yaniv Tzoreff <yanivt@...gle.com>,
Benson Leung <bleung@...gle.com>,
Steven Rostedt <rostedt@...dmis.org>,
Vincent Whitchurch <vincent.whitchurch@...s.com>,
Pekka Paalanen <ppaalanen@...il.com>,
Sean Paul <seanpaul@...omium.org>,
Daniel Vetter <daniel@...ll.ch>, linux-kernel@...r.kernel.org,
upstream@...ihalf.com
Subject: [PATCH v2 13/15] dyndbg: add support for default trace destination
Instead of repeating trace destination name explicitly for each
command (e.g. +T:thunderbolt), this change saves previously used
trace destination provided to [=+-]T as default and consecutive
commands which don't provide trace destination explicitly will
usa the saved trace destination.
Signed-off-by: Łukasz Bartosik <lb@...ihalf.com>
---
lib/dynamic_debug.c | 86 ++++++++++++++++++++++++++++++++++++++-------
1 file changed, 73 insertions(+), 13 deletions(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index dbedb1139d4b..ae05b3728520 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -101,6 +101,9 @@ struct ddebug_trace {
struct ddebug_trace_inst inst[TRACE_DST_MAX-1];
DECLARE_BITMAP(bmap, TRACE_DST_MAX-1);
int bmap_size;
+#define DST_NOT_SET (-1)
+#define DST_NOT_SET_STR "not set"
+ int default_dst;
};
static DEFINE_MUTEX(ddebug_lock);
@@ -110,7 +113,8 @@ module_param(verbose, int, 0644);
MODULE_PARM_DESC(verbose, " dynamic_debug/control processing "
"( 0 = off (default), 1 = module add/rm, 2 = >control summary, 3 = parsing, 4 = per-site changes)");
-static struct ddebug_trace tr = { .bmap_size = TRACE_DST_MAX-1 };
+static struct ddebug_trace tr = { .bmap_size = TRACE_DST_MAX-1,
+ .default_dst = DST_NOT_SET, };
static inline struct dd_ctrl *get_ctrl(struct _ddebug *desc)
{
@@ -132,6 +136,11 @@ static inline unsigned int get_trace_dst(const struct _ddebug *desc)
return desc->ctrl.trace_dst;
}
+static inline bool has_tr_default_dst(void)
+{
+ return tr.default_dst != DST_NOT_SET;
+}
+
static int find_tr_instance(const char *name)
{
int idx;
@@ -146,11 +155,16 @@ static int find_tr_instance(const char *name)
static const
char *read_T_args(const char *str, struct flag_settings *modifiers)
{
- int len, idx = TRACE_DST_MAX;
- char *end;
+ bool has_colon = *(str+1) == ':' ? true : false;
+ int len = 0, idx = TRACE_DST_MAX;
+ char *end = NULL;
- if (*(str+1) != ':')
- return str;
+ if (!has_colon) {
+ if (!has_tr_default_dst())
+ return NULL;
+ idx = tr.default_dst;
+ goto end;
+ }
str += 2;
end = strchr(str, ',');
@@ -168,8 +182,12 @@ char *read_T_args(const char *str, struct flag_settings *modifiers)
goto end;
idx = find_tr_instance(str);
- if (idx < 0)
- return NULL;
+ if (idx < 0) {
+ if (!has_tr_default_dst() ||
+ has_colon)
+ return NULL;
+ idx = tr.default_dst;
+ }
end:
modifiers->trace_dst = idx;
return end ? end : str + len;
@@ -387,6 +405,13 @@ static int handle_tr_close_cmd(const char *arg)
goto end;
}
+ /*
+ * check if default trace instance is being closed,
+ * if yes then clear default destination
+ */
+ if (tr.default_dst == idx)
+ tr.default_dst = DST_NOT_SET;
+
trace_array_put(inst->arr);
/*
* don't destroy trace instance but let user do it manually
@@ -427,6 +452,32 @@ void update_tr_dst(const struct _ddebug *desc, const struct dd_ctrl *nctrl)
tr.inst[ndst].use_cnt++;
}
+static const char *get_tr_default_dst_str(void)
+{
+ switch (tr.default_dst) {
+ case DST_NOT_SET:
+ return DST_NOT_SET_STR;
+ case TRACE_DST_MAX:
+ return DD_TR_EVENT;
+ default:
+ return tr.inst[tr.default_dst].name;
+ }
+}
+
+static void update_tr_default_dst(const struct flag_settings *modifiers)
+{
+ if (tr.default_dst == modifiers->trace_dst)
+ return;
+
+ if ((!modifiers->flags && (~modifiers->mask & _DPRINTK_FLAGS_TRACE)) ||
+ (modifiers->flags & _DPRINTK_FLAGS_TRACE)) {
+
+ tr.default_dst = modifiers->trace_dst;
+ v3pr_info("set default trace dst to idx=%d, name=%s\n",
+ tr.default_dst, get_tr_default_dst_str());
+ }
+}
+
static int ddebug_parse_cmd(char *words[], int nwords)
{
int ret;
@@ -566,6 +617,9 @@ static int ddebug_change(const struct ddebug_query *query,
if (!nfound && verbose)
pr_info("no matches for query\n");
+ if (nfound)
+ update_tr_default_dst(modifiers);
+
return nfound;
}
@@ -1590,14 +1644,20 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
}
seq_puts(m, "\n");
- if (ddebug_iter_is_last(iter) &&
- !bitmap_empty(tr.bmap, tr.bmap_size)) {
- int idx;
+ if (ddebug_iter_is_last(iter)) {
seq_puts(m, "\n");
- seq_puts(m, "Opened trace instances:\n");
- for_each_set_bit(idx, tr.bmap, tr.bmap_size)
- seq_printf(m, "%s\n", tr.inst[idx].name);
+ seq_printf(m, "Default trace destination: %s\n",
+ get_tr_default_dst_str());
+
+ if (!bitmap_empty(tr.bmap, tr.bmap_size)) {
+ int idx;
+
+ seq_puts(m, "\n");
+ seq_puts(m, "Opened trace instances:\n");
+ for_each_set_bit(idx, tr.bmap, tr.bmap_size)
+ seq_printf(m, "%s\n", tr.inst[idx].name);
+ }
}
return 0;
--
2.43.0.rc2.451.g8631bc7472-goog
Powered by blists - more mailing lists