[PATCH v3 20/34] lsm: cleanup the debug and console output in lsm_init.c
Paul Moore
paul at paul-moore.com
Thu Aug 14 22:50:29 UTC 2025
Move away from an init specific init_debug() macro to a more general
lsm_pr()/lsm_pr_cont()/lsm_pr_dbg() set of macros that are available
both before and after init. In the process we do a number of minor
changes to improve the LSM initialization output and cleanup the code
somewhat.
Reviewed-by: Casey Schaufler <casey at schaufler-ca.com>
Signed-off-by: Paul Moore <paul at paul-moore.com>
---
security/lsm.h | 11 ++++
security/lsm_init.c | 123 +++++++++++++++++++-------------------------
security/security.c | 2 +
3 files changed, 66 insertions(+), 70 deletions(-)
diff --git a/security/lsm.h b/security/lsm.h
index dbe755c45e57..8dc267977ae0 100644
--- a/security/lsm.h
+++ b/security/lsm.h
@@ -6,9 +6,20 @@
#ifndef _LSM_H_
#define _LSM_H_
+#include <linux/printk.h>
#include <linux/lsm_hooks.h>
#include <linux/lsm_count.h>
+/* LSM debugging */
+extern bool lsm_debug;
+#define lsm_pr(...) pr_info(__VA_ARGS__)
+#define lsm_pr_cont(...) pr_cont(__VA_ARGS__)
+#define lsm_pr_dbg(...) \
+ do { \
+ if (lsm_debug) \
+ pr_info(__VA_ARGS__); \
+ } while (0)
+
/* List of configured LSMs */
extern unsigned int lsm_active_cnt;
extern const struct lsm_id *lsm_idlist[];
diff --git a/security/lsm_init.c b/security/lsm_init.c
index 37593805ba9e..2f7ae26fca0f 100644
--- a/security/lsm_init.c
+++ b/security/lsm_init.c
@@ -30,13 +30,6 @@ static __initdata const char *lsm_order_legacy;
static __initdata struct lsm_info *lsm_order[MAX_LSM_COUNT + 1];
static __initdata struct lsm_info *lsm_exclusive;
-static __initdata bool debug;
-#define init_debug(...) \
- do { \
- if (debug) \
- pr_info(__VA_ARGS__); \
- } while (0)
-
#define lsm_order_for_each(iter) \
for ((iter) = lsm_order; *(iter); (iter)++)
#define lsm_for_each_raw(iter) \
@@ -77,7 +70,7 @@ __setup("lsm=", lsm_choose_lsm);
*/
static int __init lsm_debug_enable(char *str)
{
- debug = true;
+ lsm_debug = true;
return 1;
}
__setup("lsm.debug", lsm_debug_enable);
@@ -143,22 +136,28 @@ static void __init lsm_order_append(struct lsm_info *lsm, const char *src)
return;
/* Skip explicitly disabled LSMs. */
- if (lsm->enabled && !lsm_is_enabled(lsm))
- goto out;
+ if (lsm->enabled && !lsm_is_enabled(lsm)) {
+ lsm_pr_dbg("skip previously disabled LSM %s:%s\n",
+ src, lsm->id->name);
+ return;
+ }
- if (WARN(lsm_active_cnt == MAX_LSM_COUNT,
- "%s: out of LSM static calls!?\n", src)) {
+ if (lsm_active_cnt == MAX_LSM_COUNT) {
+ pr_warn("exceeded maximum LSM count on %s:%s\n",
+ src, lsm->id->name);
lsm_enabled_set(lsm, false);
- goto out;
+ return;
}
if (lsm->flags & LSM_FLAG_EXCLUSIVE) {
if (lsm_exclusive) {
- init_debug("exclusive disabled: %s\n", lsm->id->name);
+ lsm_pr_dbg("skip exclusive LSM conflict %s:%s\n",
+ src, lsm->id->name);
lsm_enabled_set(lsm, false);
- goto out;
+ return;
} else {
- init_debug("exclusive chosen: %s\n", lsm->id->name);
+ lsm_pr_dbg("select exclusive LSM %s:%s\n",
+ src, lsm->id->name);
lsm_exclusive = lsm;
}
}
@@ -167,9 +166,7 @@ static void __init lsm_order_append(struct lsm_info *lsm, const char *src)
lsm_order[lsm_active_cnt] = lsm;
lsm_idlist[lsm_active_cnt++] = lsm->id;
-out:
- init_debug("%s ordered: %s (%s)\n", src, lsm->id->name,
- lsm_is_enabled(lsm) ? "enabled" : "disabled");
+ lsm_pr_dbg("enabling LSM %s:%s\n", src, lsm->id->name);
}
/**
@@ -239,7 +236,7 @@ static void __init lsm_init_single(struct lsm_info *lsm)
if (!lsm_is_enabled(lsm))
return;
- init_debug("initializing %s\n", lsm->id->name);
+ lsm_pr_dbg("initializing %s\n", lsm->id->name);
ret = lsm->init();
WARN(ret, "%s failed to initialize: %d\n", lsm->id->name, ret);
}
@@ -266,8 +263,8 @@ static void __init lsm_order_parse(const char *list, const char *src)
if ((lsm->flags & LSM_FLAG_LEGACY_MAJOR) &&
strcmp(lsm->id->name, lsm_order_legacy)) {
lsm_enabled_set(lsm, false);
- init_debug("security=%s disabled: %s (only one legacy major LSM)\n",
- lsm_order_legacy, lsm->id->name);
+ lsm_pr_dbg("skip legacy LSM conflict %s:%s\n",
+ src, lsm->id->name);
}
}
}
@@ -310,8 +307,7 @@ static void __init lsm_order_parse(const char *list, const char *src)
if (lsm_order_exists(lsm))
continue;
lsm_enabled_set(lsm, false);
- init_debug("%s skipped: %s (not in requested order)\n",
- src, lsm->id->name);
+ lsm_pr_dbg("skip disabled LSM %s:%s\n", src, lsm->id->name);
}
}
@@ -319,7 +315,7 @@ static void __init lsm_order_parse(const char *list, const char *src)
* lsm_static_call_init - Initialize a LSM's static calls
* @hl: LSM hook list
*/
-static void __init lsm_static_call_init(struct security_hook_list *hl)
+static int __init lsm_static_call_init(struct security_hook_list *hl)
{
struct lsm_static_call *scall = hl->scalls;
int i;
@@ -331,11 +327,12 @@ static void __init lsm_static_call_init(struct security_hook_list *hl)
hl->hook.lsm_func_addr);
scall->hl = hl;
static_branch_enable(scall->active);
- return;
+ return 0;
}
scall++;
}
- panic("%s - Ran out of static slots.\n", __func__);
+
+ return -ENOSPC;
}
/**
@@ -353,7 +350,9 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
for (i = 0; i < count; i++) {
hooks[i].lsmid = lsmid;
- lsm_static_call_init(&hooks[i]);
+ if (lsm_static_call_init(&hooks[i]))
+ panic("exhausted LSM callback slots with LSM %s\n",
+ lsmid->name);
}
}
@@ -384,19 +383,16 @@ int __init security_init(void)
{
unsigned int cnt;
struct lsm_info **lsm;
- struct lsm_info *early;
- unsigned int first = 0;
- init_debug("legacy security=%s\n", lsm_order_legacy ? : " *unspecified*");
- init_debug(" CONFIG_LSM=%s\n", lsm_order_builtin);
- init_debug("boot arg lsm=%s\n", lsm_order_cmdline ? : " *unspecified*");
+ if (lsm_debug) {
+ lsm_pr("built-in LSM list: %s\n", lsm_order_builtin);
+ lsm_pr("legacy LSM parameter: %s\n", lsm_order_legacy);
+ lsm_pr("boot LSM parameter: %s\n", lsm_order_cmdline);
+ }
if (lsm_order_cmdline) {
- if (lsm_order_legacy) {
- pr_warn("security=%s is ignored because it is superseded by lsm=%s\n",
- lsm_order_legacy, lsm_order_cmdline);
+ if (lsm_order_legacy)
lsm_order_legacy = NULL;
- }
lsm_order_parse(lsm_order_cmdline, "cmdline");
} else
lsm_order_parse(lsm_order_builtin, "builtin");
@@ -404,38 +400,25 @@ int __init security_init(void)
lsm_order_for_each(lsm)
lsm_prepare(*lsm);
- pr_info("initializing lsm=");
- lsm_early_for_each_raw(early) {
- if (lsm_is_enabled(early))
- pr_cont("%s%s",
- first++ == 0 ? "" : ",", early->id->name);
+ if (lsm_debug) {
+ lsm_pr("blob(cred) size %d\n", blob_sizes.lbs_cred);
+ lsm_pr("blob(file) size %d\n", blob_sizes.lbs_file);
+ lsm_pr("blob(ib) size %d\n", blob_sizes.lbs_ib);
+ lsm_pr("blob(inode) size %d\n", blob_sizes.lbs_inode);
+ lsm_pr("blob(ipc) size %d\n", blob_sizes.lbs_ipc);
+ lsm_pr("blob(key) size %d\n", blob_sizes.lbs_key);
+ lsm_pr("blob(msg_msg)_size %d\n", blob_sizes.lbs_msg_msg);
+ lsm_pr("blob(sock) size %d\n", blob_sizes.lbs_sock);
+ lsm_pr("blob(superblock) size %d\n", blob_sizes.lbs_superblock);
+ lsm_pr("blob(perf_event) size %d\n", blob_sizes.lbs_perf_event);
+ lsm_pr("blob(task) size %d\n", blob_sizes.lbs_task);
+ lsm_pr("blob(tun_dev) size %d\n", blob_sizes.lbs_tun_dev);
+ lsm_pr("blob(xattr) count %d\n", blob_sizes.lbs_xattr_count);
+ lsm_pr("blob(bdev) size %d\n", blob_sizes.lbs_bdev);
+ lsm_pr("blob(bpf_map) size %d\n", blob_sizes.lbs_bpf_map);
+ lsm_pr("blob(bpf_prog) size %d\n", blob_sizes.lbs_bpf_prog);
+ lsm_pr("blob(bpf_token) size %d\n", blob_sizes.lbs_bpf_token);
}
- lsm_order_for_each(lsm) {
- if (lsm_is_enabled(*lsm))
- pr_cont("%s%s",
- first++ == 0 ? "" : ",", (*lsm)->id->name);
- }
- pr_cont("\n");
-
- init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
- init_debug("file blob size = %d\n", blob_sizes.lbs_file);
- init_debug("ib blob size = %d\n", blob_sizes.lbs_ib);
- init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
- init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
-#ifdef CONFIG_KEYS
- init_debug("key blob size = %d\n", blob_sizes.lbs_key);
-#endif /* CONFIG_KEYS */
- init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
- init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
- init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
- init_debug("perf event blob size = %d\n", blob_sizes.lbs_perf_event);
- init_debug("task blob size = %d\n", blob_sizes.lbs_task);
- init_debug("tun device blob size = %d\n", blob_sizes.lbs_tun_dev);
- init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count);
- init_debug("bdev blob size = %d\n", blob_sizes.lbs_bdev);
- init_debug("bpf map blob size = %d\n", blob_sizes.lbs_bpf_map);
- init_debug("bpf prog blob size = %d\n", blob_sizes.lbs_bpf_prog);
- init_debug("bpf token blob size = %d\n", blob_sizes.lbs_bpf_token);
if (blob_sizes.lbs_file)
lsm_file_cache = kmem_cache_create("lsm_file_cache",
@@ -447,9 +430,9 @@ int __init security_init(void)
SLAB_PANIC, NULL);
if (lsm_cred_alloc((struct cred *)current->cred, GFP_KERNEL))
- panic("%s: early cred alloc failed.\n", __func__);
+ panic("early LSM cred alloc failed\n");
if (lsm_task_alloc(current))
- panic("%s: early task alloc failed.\n", __func__);
+ panic("early LSM task alloc failed\n");
cnt = 0;
lsm_order_for_each(lsm) {
diff --git a/security/security.c b/security/security.c
index add46073af0c..c9642020755e 100644
--- a/security/security.c
+++ b/security/security.c
@@ -73,6 +73,8 @@ const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = {
[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
};
+bool lsm_debug __ro_after_init;
+
unsigned int lsm_active_cnt __ro_after_init;
const struct lsm_id *lsm_idlist[MAX_LSM_COUNT];
--
2.50.1
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