[Crash-utility] [PATCH V2 2/2] Fix show_module_taint() for kernel version > 4.9

[Pratyush Anand]

commit 7fd8329ba502ef76dd91db561c7aed696b2c7720 simplified module taint
flags handling. Modify crash code to cater the kernel changes.

Signed-off-by: Pratyush Anand <panand at redhat.com>
---
 defs.h    |   1 +
 kernel.c  | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 symbols.c |   1 +
 3 files changed, 102 insertions(+)

diff --git a/defs.h b/defs.h
index 8f4c6e24bcc7..e45b667064a0 100644
--- a/defs.h
+++ b/defs.h
@@ -1977,6 +1977,7 @@ struct offset_table {                    /* stash of commonly-used offsets */
 	long blk_mq_ctx_rq_dispatched;
 	long blk_mq_ctx_rq_completed;
 	long task_struct_stack;
+	long tnt_mod;
 };
 
 struct size_table {         /* stash of commonly-used sizes */
diff --git a/kernel.c b/kernel.c
index cef8583ef503..56cfd99c4fbc 100644
--- a/kernel.c
+++ b/kernel.c
@@ -21,6 +21,7 @@
 #include <elf.h>
 #include <libgen.h>
 #include <ctype.h>
+#include <stdbool.h>
 
 static void do_module_cmd(ulong, char *, ulong, char *, char *);
 static void show_module_taint(void);
@@ -3963,6 +3964,99 @@ check_specified_module_tree(char *module, char *gdb_buffer)
 }
 
 static void
+show_module_taint_4_10(void)
+{
+	int i, j, bx;
+	struct load_module *lm;
+	int maxnamelen;
+	int found;
+	char buf1[BUFSIZE];
+	char buf2[BUFSIZE];
+	struct syment *sp;
+	uint *taintsp, taints;
+	bool tnt_mod;
+	char tnt_true;
+	int tnts_len;
+	ulong tnts_addr;
+	char *modbuf;
+
+	if (INVALID_MEMBER(module_taints)) {
+		MEMBER_OFFSET_INIT(module_taints, "module", "taints");
+		STRUCT_SIZE_INIT(taint_flag, "taint_flag");
+		MEMBER_OFFSET_INIT(tnt_true, "taint_flag", "true");
+		MEMBER_OFFSET_INIT(tnt_mod, "taint_flag", "module");
+	}
+
+	modbuf = GETBUF(SIZE(module));
+
+	for (i = found = maxnamelen = 0; i < kt->mods_installed; i++) {
+		lm = &st->load_modules[i];
+
+		readmem(lm->module_struct, KVADDR, modbuf, SIZE(module),
+			"module struct", FAULT_ON_ERROR);
+
+		taints = ULONG(modbuf + OFFSET(module_taints));
+
+		if (taints) {
+			found++;
+			maxnamelen = strlen(lm->mod_name) > maxnamelen ?
+				strlen(lm->mod_name) : maxnamelen;
+		}
+	}
+
+	if (!found) {
+		fprintf(fp, "no tainted modules\n");
+		FREEBUF(modbuf);
+		return;
+	}
+
+	tnts_len = get_array_length("taint_flags", NULL, 0);
+	sp = symbol_search("taint_flags");
+	tnts_addr = sp->value;
+
+	fprintf(fp, "%s  %s\n",
+			mkstring(buf2, maxnamelen, LJUST, "NAME"), "TAINTS");
+
+	for (i = 0; i < st->mods_installed; i++) {
+
+		lm = &st->load_modules[i];
+		bx = 0;
+		buf1[0] = '\0';
+
+		readmem(lm->module_struct, KVADDR, modbuf, SIZE(module),
+				"module struct", FAULT_ON_ERROR);
+
+		taints = ULONG(modbuf + OFFSET(module_taints));
+		if (!taints)
+			continue;
+		taintsp = &taints;
+
+		for (j = 0; j < tnts_len; j++) {
+			readmem((tnts_addr + j * SIZE(taint_flag)) +
+					OFFSET(tnt_mod),
+					KVADDR, &tnt_mod, sizeof(bool),
+					"tnt mod", FAULT_ON_ERROR);
+			if (!tnt_mod)
+				continue;
+			if (NUM_IN_BITMAP(taintsp, j)) {
+				readmem((tnts_addr + j * SIZE(taint_flag)) +
+						OFFSET(tnt_true),
+						KVADDR, &tnt_true, sizeof(char),
+						"tnt true", FAULT_ON_ERROR);
+				buf1[bx++] = tnt_true;
+			}
+		}
+
+		buf1[bx++] = '\0';
+
+		fprintf(fp, "%s  %s\n", mkstring(buf2, maxnamelen,
+					LJUST, lm->mod_name), buf1);
+	}
+
+	FREEBUF(modbuf);
+}
+
+static void
 show_module_taint(void)
 {
 	int i, j, bx;
@@ -3980,6 +4074,12 @@ show_module_taint(void)
 	ulong tnts_addr;
 	char *modbuf;
 
+	if (kernel_symbol_exists("taint_flags") &&
+			STRUCT_EXISTS("taint_flag")) {
+		show_module_taint_4_10();
+		return;
+	}
+
 	if (INVALID_MEMBER(module_taints) &&
 	    INVALID_MEMBER(module_license_gplok)) {
 		MEMBER_OFFSET_INIT(module_taints, "module", "taints");
diff --git a/symbols.c b/symbols.c
index 7d66d9d1d0a4..ceeba709ae5e 100644
--- a/symbols.c
+++ b/symbols.c
@@ -8897,6 +8897,7 @@ dump_offset_table(char *spec, ulong makestruct)
 	fprintf(fp, "                       tnt_bit: %ld\n", OFFSET(tnt_bit));
 	fprintf(fp, "                      tnt_true: %ld\n", OFFSET(tnt_true));
 	fprintf(fp, "                     tnt_false: %ld\n", OFFSET(tnt_false));
+	fprintf(fp, "                       tnt_mod: %ld\n", OFFSET(tnt_mod));
 
 	fprintf(fp, "                     page_next: %ld\n", OFFSET(page_next));
 	fprintf(fp, "                     page_prev: %ld\n", OFFSET(page_prev));
-- 
2.7.4