[PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[Denis Cheng]

the original code use KOBJ_NAME_LEN for built-in module name length,
that's defined to 20 in linux/kobject.h, but this is not enough appearntly,
many module names are longer than this;
 #define KOBJ_NAME_LEN                   20

another macro is MODULE_NAME_LEN defined in linux/module.h, I think this is
enough for module names:
 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))

Signed-off-by: Denis Cheng <crquan@gmail.com>
---
 kernel/params.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/params.c b/kernel/params.c
index 7686417..a085b40 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -376,8 +376,6 @@ int param_get_string(char *buffer, struct kernel_param *kp)
 
 extern struct kernel_param __start___param[], __stop___param[];
 
-#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
-
 struct param_attribute
 {
 	struct module_attribute mattr;
@@ -588,7 +586,7 @@ static void __init param_sysfs_builtin(void)
 {
 	struct kernel_param *kp, *kp_begin = NULL;
 	unsigned int i, name_len, count = 0;
-	char modname[MAX_KBUILD_MODNAME + 1] = "";
+	char modname[MODULE_NAME_LEN + 1] = "";
 
 	for (i=0; i < __stop___param - __start___param; i++) {
 		char *dot;
@@ -596,12 +594,12 @@ static void __init param_sysfs_builtin(void)
 
 		kp = &__start___param[i];
 		max_name_len =
-			min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name));
+			min_t(size_t, MODULE_NAME_LEN, strlen(kp->name));
 
 		dot = memchr(kp->name, '.', max_name_len);
 		if (!dot) {
 			DEBUGP("couldn't find period in first %d characters "
-			       "of %s\n", MAX_KBUILD_MODNAME, kp->name);
+			       "of %s\n", MODULE_NAME_LEN, kp->name);
 			continue;
 		}
 		name_len = dot - kp->name;
-- 
1.5.3.5

Re: [PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[Rusty Russell]

On Monday 21 January 2008 20:08:25 Denis Cheng wrote:
> the original code use KOBJ_NAME_LEN for built-in module name length,
> that's defined to 20 in linux/kobject.h, but this is not enough appearntly,
> many module names are longer than this;
>  #define KOBJ_NAME_LEN                   20

Thanks, applied.  I was surprisedto learn that we have a 35-char source 
filename in the kernel.

And congratulations to nf_conntrack_l3proto_ipv4_compat.c!

Cheers,
Rusty.

Re: [PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[Jan Engelhardt]

On Jan 21 2008 22:16, Rusty Russell wrote:
>On Monday 21 January 2008 20:08:25 Denis Cheng wrote:
>> the original code use KOBJ_NAME_LEN for built-in module name length,
>> that's defined to 20 in linux/kobject.h, but this is not enough appearntly,
>> many module names are longer than this;
>>  #define KOBJ_NAME_LEN                   20
>
>Thanks, applied.  I was surprisedto learn that we have a 35-char source 
>filename in the kernel.
>
>And congratulations to nf_conntrack_l3proto_ipv4_compat.c!

But nf..dada_compat.c gets linked into nf_conntrack_ipv4.ko,
and that is what is used in /sys/module - and it fits the 20.
Any place where nf_conntrack_l3proto_ipv4_compat would still be used?

Re: [PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[rae l]

On Jan 23, 2008 7:13 AM, Jan Engelhardt <jengelh@computergmbh.de> wrote:
> But nf..dada_compat.c gets linked into nf_conntrack_ipv4.ko,
> and that is what is used in /sys/module - and it fits the 20.
> Any place where nf_conntrack_l3proto_ipv4_compat would still be used?
there is a module named nf_conntrack_proto_icmp.ko, length 23. and you
can find all them by:

$ make allmodconfig && make modules

$ find -name '*.ko' -printf '%f\n' |gawk '{print length($0), $0}' |sort -n
...
24 dvb-usb-af9005-remote.ko
24 dvb-usb-dibusb-common.ko
25 nf_conntrack_proto_gre.ko
26 nf_conntrack_netbios_ns.ko
26 nf_conntrack_proto_sctp.ko
29 nf_conntrack_proto_udplite.ko

so currently tha max length of module name is 26 (in
nf_conntrack_proto_udplite), but still no any length limit to module
names in Documentation/, so we have to prepare reserved space for
modules later, or mark MODULE_NAME_LEN as the modules' name length
limit in Documentation/?

Simply speaking, MODULE_NAME_LEN does the better job.
>

-- 
Denis Cheng

Re: [PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[Rusty Russell]

On Wednesday 23 January 2008 10:13:37 Jan Engelhardt wrote:
> On Jan 21 2008 22:16, Rusty Russell wrote:
> >On Monday 21 January 2008 20:08:25 Denis Cheng wrote:
> >> the original code use KOBJ_NAME_LEN for built-in module name length,
> >> that's defined to 20 in linux/kobject.h, but this is not enough
> >> appearntly, many module names are longer than this;
> >>  #define KOBJ_NAME_LEN                   20
> >
> >Thanks, applied.  I was surprisedto learn that we have a 35-char source
> >filename in the kernel.
> >
> >And congratulations to nf_conntrack_l3proto_ipv4_compat.c!
>
> But nf..dada_compat.c gets linked into nf_conntrack_ipv4.ko,
> and that is what is used in /sys/module - and it fits the 20.
> Any place where nf_conntrack_l3proto_ipv4_compat would still be used?

Of course, but my point was that we already have a 35 char filename in the 
kernel, and lots of > 22 chars, so increasing it is not unreasonable.

FYI make allmodconfig here gives me the following of 21 chars or longer:

dvb-usb-af9005-remote
dvb-usb-dibusb-common
nf_conntrack_netbios_ns
nf_conntrack_proto_udplite
nf_conntrack_proto_sctp
nf_conntrack_proto_gre

Cheers,
Rusty.

[PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[Denis Cheng]

the original code use KOBJ_NAME_LEN for built-in module name length,
that's defined to 20 in linux/kobject.h, but this is not enough,
some module names(such as nf_conntrack_proto_icmp) are longer than this;
 #define KOBJ_NAME_LEN                   20

another macro is MODULE_NAME_LEN defined in linux/module.h, I think this is
enough for module names:
 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))

Signed-off-by: Denis Cheng <crquan@gmail.com>
---
 kernel/params.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/params.c b/kernel/params.c
index 7686417..a085b40 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -376,8 +376,6 @@ int param_get_string(char *buffer, struct kernel_param *kp)
 
 extern struct kernel_param __start___param[], __stop___param[];
 
-#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
-
 struct param_attribute
 {
 	struct module_attribute mattr;
@@ -588,7 +586,7 @@ static void __init param_sysfs_builtin(void)
 {
 	struct kernel_param *kp, *kp_begin = NULL;
 	unsigned int i, name_len, count = 0;
-	char modname[MAX_KBUILD_MODNAME + 1] = "";
+	char modname[MODULE_NAME_LEN + 1] = "";
 
 	for (i=0; i < __stop___param - __start___param; i++) {
 		char *dot;
@@ -596,12 +594,12 @@ static void __init param_sysfs_builtin(void)
 
 		kp = &__start___param[i];
 		max_name_len =
-			min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name));
+			min_t(size_t, MODULE_NAME_LEN, strlen(kp->name));
 
 		dot = memchr(kp->name, '.', max_name_len);
 		if (!dot) {
 			DEBUGP("couldn't find period in first %d characters "
-			       "of %s\n", MAX_KBUILD_MODNAME, kp->name);
+			       "of %s\n", MODULE_NAME_LEN, kp->name);
 			continue;
 		}
 		name_len = dot - kp->name;
-- 
1.5.3.5

[PATCH] kernel/params.c: fix the module name length in param_sysfs_builtin

[rae l]

From: Denis Cheng <crquan@gmail.com>
Date: Sat, 19 Jan 2008 13:29:51 +0800
Subject: [PATCH] kernel/params.c: fix the module name length in
param_sysfs_builtin

the original code use KOBJ_NAME_LEN for built-in module name length,
that's defined to 20 in linux/kobject.h, but this is not enough appearntly,
many module names are longer than this;
 #define KOBJ_NAME_LEN                   20

another macro is MODULE_NAME_LEN defined in linux/module.h, I think this is
enough for module names:
 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))

Signed-off-by: Denis Cheng <crquan@gmail.com>
---
 kernel/params.c |    8 +++-----
 1 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/params.c b/kernel/params.c
index 7686417..a085b40 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -376,8 +376,6 @@ int param_get_string(char *buffer, struct kernel_param *kp)

 extern struct kernel_param __start___param[], __stop___param[];

-#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
-
 struct param_attribute
 {
 	struct module_attribute mattr;
@@ -588,7 +586,7 @@ static void __init param_sysfs_builtin(void)
 {
 	struct kernel_param *kp, *kp_begin = NULL;
 	unsigned int i, name_len, count = 0;
-	char modname[MAX_KBUILD_MODNAME + 1] = "";
+	char modname[MODULE_NAME_LEN + 1] = "";

 	for (i=0; i < __stop___param - __start___param; i++) {
 		char *dot;
@@ -596,12 +594,12 @@ static void __init param_sysfs_builtin(void)

 		kp = &__start___param[i];
 		max_name_len =
-			min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name));
+			min_t(size_t, MODULE_NAME_LEN, strlen(kp->name));

 		dot = memchr(kp->name, '.', max_name_len);
 		if (!dot) {
 			DEBUGP("couldn't find period in first %d characters "
-			       "of %s\n", MAX_KBUILD_MODNAME, kp->name);
+			       "of %s\n", MODULE_NAME_LEN, kp->name);
 			continue;
 		}
 		name_len = dot - kp->name;
-- 
1.5.3.5

-- 
Denis Cheng