6:39 a.m.
The goal of this patchset is to explicitly indicate to the
user that the Linux kernel is "tainted" at init-time or
when the 'sys' command is used. In additional to the above
show_kernel_taints() has been consolidated to avoid
duplication and hopefully improve readability.
Aaron Tomlin (3):
kernel: consolidate show_kernel_taints()
kernel: Introduce is_kernel_tainted()
kernel: show that the kernel is tainted at init-time
kernel.c | 210 ++++++++++++++++++++++++++-----------------------------
1 file changed, 98 insertions(+), 112 deletions(-)
--
2.31.1
6:39 a.m.
New subject: [PATCH 1/3] kernel: consolidate show_kernel_taints()
No functional change.
Signed-off-by: Aaron Tomlin <atomlin(a)redhat.com>
---
kernel.c | 182 ++++++++++++++++++++++---------------------------------
1 file changed, 74 insertions(+), 108 deletions(-)
diff --git a/kernel.c b/kernel.c
index 3ead4bb..1310f98 100644
--- a/kernel.c
+++ b/kernel.c
@@ -11212,72 +11212,6 @@ dump_variable_length_record(void)
hq_close();
}
-static void
-show_kernel_taints_v4_10(char *buf, int verbose)
-{
- int i, bx;
- char tnt_true, tnt_false;
- int tnts_len;
- ulong tnts_addr;
- ulong tainted_mask, *tainted_mask_ptr;
- struct syment *sp;
-
- if (!(VALID_STRUCT(taint_flag) &&
- VALID_MEMBER(tnt_true) && VALID_MEMBER(tnt_false))) {
- STRUCT_SIZE_INIT(taint_flag, "taint_flag");
- MEMBER_OFFSET_INIT(tnt_true, "taint_flag", "true");
- MEMBER_OFFSET_INIT(tnt_false, "taint_flag", "false");
- if (INVALID_MEMBER(tnt_true)) {
- MEMBER_OFFSET_INIT(tnt_true, "taint_flag", "c_true");
- MEMBER_OFFSET_INIT(tnt_false, "taint_flag", "c_false");
- }
- }
-
- bx = 0;
- buf[0] = '\0';
-
- /*
- * Make sure that all dependencies are valid to prevent
- * a fatal error from killing the session during the
- * pre-RUNTIME system banner display.
- */
- if (!(pc->flags & RUNTIME)) {
- if (INVALID_MEMBER(tnt_true) || INVALID_MEMBER(tnt_false) ||
- !kernel_symbol_exists("tainted_mask"))
- return;
- }
-
- tnts_len = get_array_length("taint_flags", NULL, 0);
- sp = symbol_search("taint_flags");
- tnts_addr = sp->value;
-
- get_symbol_data("tainted_mask", sizeof(ulong), &tainted_mask);
- tainted_mask_ptr = &tainted_mask;
-
- for (i = 0; i < tnts_len; i++) {
- if (NUM_IN_BITMAP(tainted_mask_ptr, i)) {
- readmem((tnts_addr + i * SIZE(taint_flag)) +
- OFFSET(tnt_true),
- KVADDR, &tnt_true, sizeof(char),
- "tnt true", FAULT_ON_ERROR);
- buf[bx++] = tnt_true;
- } else {
- readmem((tnts_addr + i * SIZE(taint_flag)) +
- OFFSET(tnt_false),
- KVADDR, &tnt_false, sizeof(char),
- "tnt false", FAULT_ON_ERROR);
- if (tnt_false != ' ' && tnt_false != '-' &&
- tnt_false != 'G')
- buf[bx++] = tnt_false;
- }
- }
-
- buf[bx++] = '\0';
-
- if (verbose)
- fprintf(fp, "TAINTED_MASK: %lx %s\n", tainted_mask, buf);
-}
-
static void
show_kernel_taints(char *buf, int verbose)
{
@@ -11290,58 +11224,90 @@ show_kernel_taints(char *buf, int verbose)
int tainted;
struct syment *sp;
- if (VALID_STRUCT(taint_flag) ||
- (kernel_symbol_exists("taint_flags") &&
STRUCT_EXISTS("taint_flag"))) {
- show_kernel_taints_v4_10(buf, verbose);
+ if (kernel_symbol_exists("tainted")) {
+ get_symbol_data("tainted", sizeof(int), &tainted);
+ if (verbose)
+ fprintf(fp, "TAINTED: %x\n", tainted);
return;
- }
-
- if (!VALID_STRUCT(tnt)) {
- STRUCT_SIZE_INIT(tnt, "tnt");
- MEMBER_OFFSET_INIT(tnt_bit, "tnt", "bit");
- MEMBER_OFFSET_INIT(tnt_true, "tnt", "true");
- MEMBER_OFFSET_INIT(tnt_false, "tnt", "false");
- }
+ } else if (VALID_STRUCT(tnt) ||
+ (kernel_symbol_exists("tnts") && STRUCT_EXISTS("tnt")))
{
+ if (!VALID_STRUCT(tnt)) {
+ STRUCT_SIZE_INIT(tnt, "tnt");
+ MEMBER_OFFSET_INIT(tnt_bit, "tnt", "bit");
+ MEMBER_OFFSET_INIT(tnt_true, "tnt", "true");
+ MEMBER_OFFSET_INIT(tnt_false, "tnt", "false");
+ }
- if (VALID_STRUCT(tnt) && (sp = symbol_search("tnts"))) {
tnts_len = get_array_length("tnts", NULL, 0);
- tnts_addr = sp->value;
- } else
- tnts_addr = tnts_len = 0;
-
- bx = 0;
- buf[0] = '\0';
+ sp = symbol_search("tnts");
+ } else if (VALID_STRUCT(taint_flag) ||
+ (kernel_symbol_exists("taint_flags") &&
STRUCT_EXISTS("taint_flag"))) {
+ if (!(VALID_STRUCT(taint_flag) &&
+ VALID_MEMBER(tnt_true) && VALID_MEMBER(tnt_false))) {
+ STRUCT_SIZE_INIT(taint_flag, "taint_flag");
+ MEMBER_OFFSET_INIT(tnt_true, "taint_flag", "true");
+ MEMBER_OFFSET_INIT(tnt_false, "taint_flag", "false");
+ if (INVALID_MEMBER(tnt_true)) {
+ MEMBER_OFFSET_INIT(tnt_true, "taint_flag", "c_true");
+ MEMBER_OFFSET_INIT(tnt_false, "taint_flag", "c_false");
+ }
+ }
- tainted_mask = tainted = 0;
+ if (!(pc->flags & RUNTIME)) {
+ if (INVALID_MEMBER(tnt_true) || INVALID_MEMBER(tnt_false) ||
+ !kernel_symbol_exists("tainted_mask"))
+ return;
+ }
- if (kernel_symbol_exists("tainted_mask")) {
- get_symbol_data("tainted_mask", sizeof(ulong), &tainted_mask);
- tainted_mask_ptr = &tainted_mask;
- } else if (kernel_symbol_exists("tainted")) {
- get_symbol_data("tainted", sizeof(int), &tainted);
- if (verbose)
- fprintf(fp, "TAINTED: %x\n", tainted);
- return;
+ tnts_len = get_array_length("taint_flags", NULL, 0);
+ sp = symbol_search("taint_flags");
} else if (verbose)
option_not_supported('t');
- for (i = 0; i < (tnts_len * SIZE(tnt)); i += SIZE(tnt)) {
- readmem((tnts_addr + i) + OFFSET(tnt_bit),
- KVADDR, &tnt_bit, sizeof(uint8_t),
- "tnt bit", FAULT_ON_ERROR);
+ tnts_addr = sp->value;
+ get_symbol_data("tainted_mask", sizeof(ulong), &tainted_mask);
+ tainted_mask_ptr = &tainted_mask;
+
+ bx = 0;
+ buf[0] = '\0';
- if (NUM_IN_BITMAP(tainted_mask_ptr, tnt_bit)) {
- readmem((tnts_addr + i) + OFFSET(tnt_true),
- KVADDR, &tnt_true, sizeof(char),
- "tnt true", FAULT_ON_ERROR);
+ if (VALID_STRUCT(tnt)) {
+ for (i = 0; i < (tnts_len * SIZE(tnt)); i += SIZE(tnt)) {
+ readmem((tnts_addr + i) + OFFSET(tnt_bit),
+ KVADDR, &tnt_bit, sizeof(uint8_t),
+ "tnt bit", FAULT_ON_ERROR);
+
+ if (NUM_IN_BITMAP(tainted_mask_ptr, tnt_bit)) {
+ readmem((tnts_addr + i) + OFFSET(tnt_true),
+ KVADDR, &tnt_true, sizeof(char),
+ "tnt true", FAULT_ON_ERROR);
+ buf[bx++] = tnt_true;
+ } else {
+ readmem((tnts_addr + i) + OFFSET(tnt_false),
+ KVADDR, &tnt_false, sizeof(char),
+ "tnt false", FAULT_ON_ERROR);
+ if (tnt_false != ' ' && tnt_false != '-' &&
+ tnt_false != 'G')
+ buf[bx++] = tnt_false;
+ }
+ }
+ } else if (VALID_STRUCT(taint_flag)) {
+ for (i = 0; i < tnts_len; i++) {
+ if (NUM_IN_BITMAP(tainted_mask_ptr, i)) {
+ readmem((tnts_addr + i * SIZE(taint_flag)) +
+ OFFSET(tnt_true),
+ KVADDR, &tnt_true, sizeof(char),
+ "tnt true", FAULT_ON_ERROR);
buf[bx++] = tnt_true;
- } else {
- readmem((tnts_addr + i) + OFFSET(tnt_false),
- KVADDR, &tnt_false, sizeof(char),
- "tnt false", FAULT_ON_ERROR);
- if (tnt_false != ' ' && tnt_false != '-' &&
- tnt_false != 'G')
- buf[bx++] = tnt_false;
+ } else {
+ readmem((tnts_addr + i * SIZE(taint_flag)) +
+ OFFSET(tnt_false),
+ KVADDR, &tnt_false, sizeof(char),
+ "tnt false", FAULT_ON_ERROR);
+ if (tnt_false != ' ' && tnt_false != '-' &&
+ tnt_false != 'G')
+ buf[bx++] = tnt_false;
+ }
}
}
--
2.31.1
6:39 a.m.
New subject: [PATCH 2/3] kernel: Introduce is_kernel_tainted()
Provide a quick way to test if the given Linux kernel is "tainted".
Support for Linux-2.6.12 and above, to date.
Signed-off-by: Aaron Tomlin <atomlin(a)redhat.com>
---
kernel.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/kernel.c b/kernel.c
index 1310f98..553849c 100644
--- a/kernel.c
+++ b/kernel.c
@@ -5482,6 +5482,24 @@ cmd_sys(void)
} while (args[optind]);
}
+static int
+is_kernel_tainted(void)
+{
+ ulong tainted_mask;
+ int tainted;
+
+ if (kernel_symbol_exists("tainted")) {
+ get_symbol_data("tainted", sizeof(int), &tainted);
+ if (tainted)
+ return TRUE;
+ } else if (kernel_symbol_exists("tainted_mask")) {
+ get_symbol_data("tainted_mask", sizeof(ulong), &tainted_mask);
+ if (tainted_mask)
+ return TRUE;
+ }
+ return FALSE;
+}
+
static int
is_livepatch(void)
{
--
2.31.1
6:39 a.m.
New subject: [PATCH 3/3] kernel: show that the kernel is tainted at init-time
Explicitly indicate to the user that the Linux kernel is tainted
at init-time or when the 'sys' command is used.
Signed-off-by: Aaron Tomlin <atomlin(a)redhat.com>
---
kernel.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/kernel.c b/kernel.c
index 553849c..d98c37e 100644
--- a/kernel.c
+++ b/kernel.c
@@ -5563,16 +5563,18 @@ display_sys_stats(void)
}
} else {
if (pc->system_map) {
- fprintf(fp, " SYSTEM MAP: %s%s\n", pc->system_map,
- is_livepatch() ? " [LIVEPATCH]" : "");
+ fprintf(fp, " SYSTEM MAP: %s%s%s\n", pc->system_map,
+ is_livepatch() ? " [LIVEPATCH]" : "",
+ is_kernel_tainted() ? " [TAINTED]" : "");
fprintf(fp, "DEBUG KERNEL: %s %s\n",
pc->namelist_orig ?
pc->namelist_orig : pc->namelist,
debug_kernel_version(pc->namelist));
} else
- fprintf(fp, " KERNEL: %s%s\n", pc->namelist_orig ?
+ fprintf(fp, " KERNEL: %s%s%s\n", pc->namelist_orig ?
pc->namelist_orig : pc->namelist,
- is_livepatch() ? " [LIVEPATCH]" : "");
+ is_livepatch() ? " [LIVEPATCH]" : "",
+ is_kernel_tainted() ? " [TAINTED]" : "");
}
if (pc->debuginfo_file) {
--
2.31.1
2:58 a.m.
New subject: [PATCH 0/3] Show that the kernel is tainted at init-time
Hi Aaron,
sorry for the delay.
-----Original Message-----
The goal of this patchset is to explicitly indicate to the
user that the Linux kernel is "tainted" at init-time or
when the 'sys' command is used. In additional to the above
show_kernel_taints() has been consolidated to avoid
duplication and hopefully improve readability.
That would be usuful and looks more readable, thanks.
To stop the compilation warning below, with initializing the variables,
Acked-by: Kazuhito Hagio <k-hagio-ab(a)nec.com>
cc -c -g -DX86_64 -DLZO -DSNAPPY -DZSTD -DGDB_10_2 kernel.c -Wall -O2 -Wstrict-prototypes
-Wmissing-prototypes -fstack-protector -Wformat-security
kernel.c: In function ‘show_kernel_taints’:
kernel.c:11268:12: warning: ‘sp’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
tnts_addr = sp->value;
~~~~~~~~~~^~~~~~~~~~~
kernel.c:11222:6: warning: ‘tnts_len’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
int tnts_len;
^~~~~~~~
--- a/kernel.c
+++ b/kernel.c
@@ -11219,11 +11219,11 @@ show_kernel_taints(char *buf, int verbose)
int i, bx;
uint8_t tnt_bit;
char tnt_true, tnt_false;
- int tnts_len;
+ int tnts_len = 0;
ulong tnts_addr;
ulong tainted_mask, *tainted_mask_ptr;
int tainted;
- struct syment *sp;
+ struct syment *sp = NULL;
if (kernel_symbol_exists("tainted")) {
get_symbol_data("tainted", sizeof(int), &tainted);
Aaron Tomlin (3):
kernel: consolidate show_kernel_taints()
kernel: Introduce is_kernel_tainted()
kernel: show that the kernel is tainted at init-time
kernel.c | 210 ++++++++++++++++++++++++++-----------------------------
1 file changed, 98 insertions(+), 112 deletions(-)
--
2.31.1
--
Crash-utility mailing list
Crash-utility(a)redhat.com
https://listman.redhat.com/mailman/listinfo/crash-utility
8:56 a.m.
New subject: [PATCH 0/3] Show that the kernel is tainted at init-time
On Mon 2021-11-15 08:58 +0000, HAGIO KAZUHITO(萩尾 一仁) wrote:
sorry for the delay.
No problem.
> The goal of this patchset is to explicitly indicate to the
> user that the Linux kernel is "tainted" at init-time or
> when the 'sys' command is used. In additional to the above
> show_kernel_taints() has been consolidated to avoid
> duplication and hopefully improve readability.
That would be usuful and looks more readable, thanks.
To stop the compilation warning below, with initializing the variables,
Acked-by: Kazuhito Hagio <k-hagio-ab(a)nec.com>
Thanks,
--
Aaron Tomlin
1107
days inactive
1121
days old
devel@lists.crash-utility.osci.io
5 comments
2 participants
participants (2)
-
Aaron Tomlin -
HAGIO KAZUHITO(萩尾 一仁)