From: Lucas De Marchi <lucas.demarchi@intel.com>
To: linux-modules@vger.kernel.org
Cc: Jiri Slaby <jirislaby@kernel.org>, Jessica Yu <jeyu@kernel.org>,
Giovanni Gherdovich <ggherdovich@suse.cz>
Subject: [PATCH 2/4] libkmod-config: re-quote option from kernel cmdline
Date: Fri, 12 Feb 2021 01:45:22 -0800 [thread overview]
Message-ID: <20210212094524.170861-2-lucas.demarchi@intel.com> (raw)
In-Reply-To: <20210212094524.170861-1-lucas.demarchi@intel.com>
It was reported that grub mangles the kernel cmdline. It turns
acpi_cpufreq.dyndbg="file drivers/cpufreq/acpi-cpufreq.c +mpf"
into
"acpi_cpufreq.dyndbg=file drivers/cpufreq/acpi-cpufreq.c +mpf"
However, even though we could blame grub for doing that, the kernel
happily accepts and re-quotes it when the module is built-in.
So, it's better if kmod also understands it this way and does the same.
Here we basically add additional code to un-mangle it, moving the quote
in way that is acceptable to pass through init_module(). Note that the
interface [f]init_module() gives us mandates the quote to be part of the
value: the module name is not passed and the options are separated by
space.
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://bugzilla.suse.com/show_bug.cgi?id=1181111#c10
---
libkmod/libkmod-config.c | 36 ++++++++++++-
.../module-param-kcmdline7/correct.txt | 5 ++
.../module-param-kcmdline7/correct.txt | 5 ++
.../module-param-kcmdline7/proc/cmdline | 1 +
.../module-param-kcmdline7/proc/cmdline | 1 +
.../module-param-kcmdline8/correct.txt | 5 ++
.../module-param-kcmdline7/correct.txt | 5 ++
.../module-param-kcmdline7/proc/cmdline | 1 +
.../module-param-kcmdline8/proc/cmdline | 1 +
testsuite/test-modprobe.c | 50 +++++++++++++++++++
10 files changed, 109 insertions(+), 1 deletion(-)
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/correct.txt
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/correct.txt
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/proc/cmdline
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/proc/cmdline
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/correct.txt
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/correct.txt
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/proc/cmdline
create mode 100644 testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/proc/cmdline
diff --git a/libkmod/libkmod-config.c b/libkmod/libkmod-config.c
index d3cd10d..2873f06 100644
--- a/libkmod/libkmod-config.c
+++ b/libkmod/libkmod-config.c
@@ -498,7 +498,7 @@ static int kmod_config_parse_kcmdline(struct kmod_config *config)
{
char buf[KCMD_LINE_SIZE];
int fd, err;
- char *p, *modname, *param = NULL, *value = NULL;
+ char *p, *p_quote_start, *modname, *param = NULL, *value = NULL;
bool is_quoted = false, iter = true;
enum state {
STATE_IGNORE,
@@ -524,10 +524,23 @@ static int kmod_config_parse_kcmdline(struct kmod_config *config)
}
state = STATE_MODNAME;
+ p_quote_start = NULL;
for (p = buf, modname = buf; iter; p++) {
switch (*p) {
case '"':
is_quoted = !is_quoted;
+
+ /*
+ * only allow starting quote as first char when looking
+ * for a modname: anything else is considered ill-formed
+ */
+ if (is_quoted && state == STATE_MODNAME && p == modname) {
+ p_quote_start = p;
+ modname = p + 1;
+ } else if (state != STATE_VALUE) {
+ state = STATE_IGNORE;
+ }
+
break;
case '\0':
case '\n':
@@ -550,6 +563,7 @@ static int kmod_config_parse_kcmdline(struct kmod_config *config)
*/
modname = p + 1;
state = STATE_MODNAME;
+ p_quote_start = NULL;
}
break;
case '.':
@@ -576,10 +590,30 @@ static int kmod_config_parse_kcmdline(struct kmod_config *config)
}
if (state == STATE_COMPLETE) {
+ /*
+ * We may need to re-quote to unmangle what the
+ * bootloader passed. Example: grub passes the option as
+ * "parport.dyndbg=file drivers/parport/ieee1284_ops.c +mpf"
+ * instead of
+ * parport.dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
+ */
+ if (p_quote_start && p_quote_start < modname) {
+ /*
+ * p_quote_start
+ * |
+ * |modname param value
+ * || | |
+ * vv v v
+ * "parport\0dyndbg=file drivers/parport/ieee1284_ops.c +mpf" */
+ memmove(p_quote_start, modname, value - modname);
+ value--; modname--; param--;
+ *value = '"';
+ }
kcmdline_parse_result(config, modname, param, value);
/* start over on next iteration */
modname = p + 1;
state = STATE_MODNAME;
+ p_quote_start = NULL;
}
}
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/correct.txt b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/correct.txt
new file mode 100644
index 0000000..d80da6d
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/correct.txt
@@ -0,0 +1,5 @@
+options psmouse foo
+options parport dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
+
+# End of configuration files. Dumping indexes now:
+
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/correct.txt b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/correct.txt
new file mode 100644
index 0000000..d80da6d
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/correct.txt
@@ -0,0 +1,5 @@
+options psmouse foo
+options parport dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
+
+# End of configuration files. Dumping indexes now:
+
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/proc/cmdline b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/proc/cmdline
new file mode 100644
index 0000000..86f9052
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/module-param-kcmdline7/proc/cmdline
@@ -0,0 +1 @@
+psmouse.foo parport.dyndbg="file drivers/parport/ieee1284_ops.c +mpf" quiet rw
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/proc/cmdline b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/proc/cmdline
new file mode 100644
index 0000000..86f9052
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline7/proc/cmdline
@@ -0,0 +1 @@
+psmouse.foo parport.dyndbg="file drivers/parport/ieee1284_ops.c +mpf" quiet rw
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/correct.txt b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/correct.txt
new file mode 100644
index 0000000..d80da6d
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/correct.txt
@@ -0,0 +1,5 @@
+options psmouse foo
+options parport dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
+
+# End of configuration files. Dumping indexes now:
+
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/correct.txt b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/correct.txt
new file mode 100644
index 0000000..d80da6d
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/correct.txt
@@ -0,0 +1,5 @@
+options psmouse foo
+options parport dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
+
+# End of configuration files. Dumping indexes now:
+
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/proc/cmdline b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/proc/cmdline
new file mode 100644
index 0000000..86f9052
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/module-param-kcmdline7/proc/cmdline
@@ -0,0 +1 @@
+psmouse.foo parport.dyndbg="file drivers/parport/ieee1284_ops.c +mpf" quiet rw
diff --git a/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/proc/cmdline b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/proc/cmdline
new file mode 100644
index 0000000..eab04ad
--- /dev/null
+++ b/testsuite/rootfs-pristine/test-modprobe/module-param-kcmdline8/proc/cmdline
@@ -0,0 +1 @@
+psmouse.foo "parport.dyndbg=file drivers/parport/ieee1284_ops.c +mpf" quiet rw
diff --git a/testsuite/test-modprobe.c b/testsuite/test-modprobe.c
index f6bed8b..dbc54f3 100644
--- a/testsuite/test-modprobe.c
+++ b/testsuite/test-modprobe.c
@@ -359,6 +359,56 @@ DEFINE_TEST(modprobe_param_kcmdline6,
);
+static noreturn int modprobe_param_kcmdline7(const struct test *t)
+{
+ const char *progname = ABS_TOP_BUILDDIR "/tools/modprobe";
+ const char *const args[] = {
+ progname,
+ "-c",
+ NULL,
+ };
+
+ test_spawn_prog(progname, args);
+ exit(EXIT_FAILURE);
+}
+DEFINE_TEST(modprobe_param_kcmdline7,
+ .description = "check if dots on other parts of kcmdline don't confuse our parser",
+ .config = {
+ [TC_UNAME_R] = "4.4.4",
+ [TC_ROOTFS] = TESTSUITE_ROOTFS "test-modprobe/module-param-kcmdline7",
+ },
+ .output = {
+ .out = TESTSUITE_ROOTFS "test-modprobe/module-param-kcmdline7/correct.txt",
+ },
+ .modules_loaded = "",
+ );
+
+
+static noreturn int modprobe_param_kcmdline8(const struct test *t)
+{
+ const char *progname = ABS_TOP_BUILDDIR "/tools/modprobe";
+ const char *const args[] = {
+ progname,
+ "-c",
+ NULL,
+ };
+
+ test_spawn_prog(progname, args);
+ exit(EXIT_FAILURE);
+}
+DEFINE_TEST(modprobe_param_kcmdline8,
+ .description = "check if dots on other parts of kcmdline don't confuse our parser",
+ .config = {
+ [TC_UNAME_R] = "4.4.4",
+ [TC_ROOTFS] = TESTSUITE_ROOTFS "test-modprobe/module-param-kcmdline8",
+ },
+ .output = {
+ .out = TESTSUITE_ROOTFS "test-modprobe/module-param-kcmdline8/correct.txt",
+ },
+ .modules_loaded = "",
+ );
+
+
static noreturn int modprobe_force(const struct test *t)
{
const char *progname = ABS_TOP_BUILDDIR "/tools/modprobe";
--
2.30.0
next prev parent reply other threads:[~2021-02-12 9:46 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-12 9:45 [PATCH 1/4] libkmod-config: revamp kcmdline parsing into a state machine Lucas De Marchi
2021-02-12 9:45 ` Lucas De Marchi [this message]
2021-02-15 15:28 ` [PATCH 2/4] libkmod-config: re-quote option from kernel cmdline Jessica Yu
2021-02-15 20:18 ` Lucas De Marchi
2021-02-12 9:45 ` [PATCH 3/4] testsuite: allow to re-use single function for tests Lucas De Marchi
2021-02-12 9:45 ` [PATCH 4/4] test-modprobe: share single function for kcmdline tests Lucas De Marchi
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