The binary interface to the namespace sysctls was never implemented
resulting in some really weird things if you attempted to use
sys_sysctl to read your hostname for example.
This patch series simples the code a little and implements the binary
sysctl interface.
In testing this patch series I discovered that our 32bit compatibility
for the binary sysctl interface is imperfect. In particular
KERN_SHMMAX and KERN_SMMALL are size_t sized quantities and are
returned as 8 bytes on to 32bit binaries using a x86_64 kernel.
However this has existing for a long time so it is not a new
regression with the namespace work.
Gads the whole sysctl thing needs work before it stops being easy
to shoot yourself in the foot.
Looking forward a little bit we need a better way to handle sysctls
and namespaces as our current technique will not work for the network
namespace. I think something based on the current overlapping sysctl
trees will work but the proc side needs to be redone before we can
use it.
Eric
The problem: When using sys_sysctl we don't read the proper values
for the variables exported from the uts namespace, nor do we do the
proper locking.
This patch introduces sysctl_uts_string which properly fetches the values
and does the proper locking.
Signed-off-by: Eric W. Biederman <[email protected]>
---
kernel/sysctl.c | 37 ++++++++++++++++++++++++++++++++-----
1 files changed, 32 insertions(+), 5 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 0521884..63db5a5 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -136,6 +136,10 @@ #endif
static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
+static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen, void **context);
+
#ifdef CONFIG_PROC_SYSCTL
static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
@@ -257,7 +261,7 @@ static ctl_table kern_table[] = {
.maxlen = sizeof(init_uts_ns.name.sysname),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
+ .strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_OSRELEASE,
@@ -266,7 +270,7 @@ static ctl_table kern_table[] = {
.maxlen = sizeof(init_uts_ns.name.release),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
+ .strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_VERSION,
@@ -275,7 +279,7 @@ static ctl_table kern_table[] = {
.maxlen = sizeof(init_uts_ns.name.version),
.mode = 0444,
.proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
+ .strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_NODENAME,
@@ -284,7 +288,7 @@ static ctl_table kern_table[] = {
.maxlen = sizeof(init_uts_ns.name.nodename),
.mode = 0644,
.proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
+ .strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_DOMAINNAME,
@@ -293,7 +297,7 @@ static ctl_table kern_table[] = {
.maxlen = sizeof(init_uts_ns.name.domainname),
.mode = 0644,
.proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
+ .strategy = &sysctl_uts_string,
},
{
.ctl_name = KERN_PANIC,
@@ -2600,6 +2604,23 @@ int sysctl_ms_jiffies(ctl_table *table,
return 1;
}
+
+/* The generic string strategy routine: */
+static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen, void **context)
+{
+ struct ctl_table uts_table;
+ int r, write;
+ write = newval && newlen;
+ memcpy(&uts_table, table, sizeof(uts_table));
+ uts_table.data = get_uts(table, write);
+ r = sysctl_string(&uts_table, name, nlen,
+ oldval, oldlenp, newval, newlen, context);
+ put_uts(table, write, uts_table.data);
+ return r;
+}
+
#else /* CONFIG_SYSCTL_SYSCALL */
@@ -2664,6 +2685,12 @@ int sysctl_ms_jiffies(ctl_table *table,
return -ENOSYS;
}
+static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen, void **context)
+{
+ return -ENOSYS;
+}
#endif /* CONFIG_SYSCTL_SYSCALL */
/*
--
1.4.2.rc3.g7e18e-dirty
This patch introduces get_uts and put_uts (used later)
and removes most of the special cases for when UTS namespace is compiled in.
Signed-off-by: Eric W. Biederman <[email protected]>
---
kernel/sysctl.c | 128 +++++++++++--------------------------------------------
1 files changed, 26 insertions(+), 102 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 09e569f..0521884 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -162,6 +162,28 @@ #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
int sysctl_legacy_va_layout;
#endif
+static void *get_uts(ctl_table *table, int write)
+{
+ char *which = table->data;
+#ifdef CONFIG_UTS_NS
+ struct uts_namespace *uts_ns = current->nsproxy->uts_ns;
+ which = (which - (char *)&init_uts_ns) + (char *)uts_ns;
+#endif
+ if (!write)
+ down_read(&uts_sem);
+ else
+ down_write(&uts_sem);
+ return which;
+}
+
+static void put_uts(ctl_table *table, int write, void *which)
+{
+ if (!write)
+ up_read(&uts_sem);
+ else
+ up_write(&uts_sem);
+}
+
/* /proc declarations: */
#ifdef CONFIG_PROC_SYSCTL
@@ -228,7 +250,6 @@ #endif
};
static ctl_table kern_table[] = {
-#ifndef CONFIG_UTS_NS
{
.ctl_name = KERN_OSTYPE,
.procname = "ostype",
@@ -274,54 +295,6 @@ #ifndef CONFIG_UTS_NS
.proc_handler = &proc_do_uts_string,
.strategy = &sysctl_string,
},
-#else /* !CONFIG_UTS_NS */
- {
- .ctl_name = KERN_OSTYPE,
- .procname = "ostype",
- .data = NULL,
- /* could maybe use __NEW_UTS_LEN here? */
- .maxlen = FIELD_SIZEOF(struct new_utsname, sysname),
- .mode = 0444,
- .proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
- },
- {
- .ctl_name = KERN_OSRELEASE,
- .procname = "osrelease",
- .data = NULL,
- .maxlen = FIELD_SIZEOF(struct new_utsname, release),
- .mode = 0444,
- .proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
- },
- {
- .ctl_name = KERN_VERSION,
- .procname = "version",
- .data = NULL,
- .maxlen = FIELD_SIZEOF(struct new_utsname, version),
- .mode = 0444,
- .proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
- },
- {
- .ctl_name = KERN_NODENAME,
- .procname = "hostname",
- .data = NULL,
- .maxlen = FIELD_SIZEOF(struct new_utsname, nodename),
- .mode = 0644,
- .proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
- },
- {
- .ctl_name = KERN_DOMAINNAME,
- .procname = "domainname",
- .data = NULL,
- .maxlen = FIELD_SIZEOF(struct new_utsname, domainname),
- .mode = 0644,
- .proc_handler = &proc_do_uts_string,
- .strategy = &sysctl_string,
- },
-#endif /* !CONFIG_UTS_NS */
{
.ctl_name = KERN_PANIC,
.procname = "panic",
@@ -1755,66 +1728,17 @@ int proc_dostring(ctl_table *table, int
* Special case of dostring for the UTS structure. This has locks
* to observe. Should this be in kernel/sys.c ????
*/
-
-#ifndef CONFIG_UTS_NS
-static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
- void __user *buffer, size_t *lenp, loff_t *ppos)
-{
- int r;
- if (!write) {
- down_read(&uts_sem);
- r=proc_dostring(table,0,filp,buffer,lenp, ppos);
- up_read(&uts_sem);
- } else {
- down_write(&uts_sem);
- r=proc_dostring(table,1,filp,buffer,lenp, ppos);
- up_write(&uts_sem);
- }
- return r;
-}
-#else /* !CONFIG_UTS_NS */
static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int r;
- struct uts_namespace* uts_ns = current->nsproxy->uts_ns;
- char* which;
-
- switch (table->ctl_name) {
- case KERN_OSTYPE:
- which = uts_ns->name.sysname;
- break;
- case KERN_NODENAME:
- which = uts_ns->name.nodename;
- break;
- case KERN_OSRELEASE:
- which = uts_ns->name.release;
- break;
- case KERN_VERSION:
- which = uts_ns->name.version;
- break;
- case KERN_DOMAINNAME:
- which = uts_ns->name.domainname;
- break;
- default:
- r = -EINVAL;
- goto out;
- }
-
- if (!write) {
- down_read(&uts_sem);
- r=_proc_do_string(which,table->maxlen,0,filp,buffer,lenp, ppos);
- up_read(&uts_sem);
- } else {
- down_write(&uts_sem);
- r=_proc_do_string(which,table->maxlen,1,filp,buffer,lenp, ppos);
- up_write(&uts_sem);
- }
- out:
+ void *which;
+ which = get_uts(table, write);
+ r = _proc_do_string(which, table->maxlen,write,filp,buffer,lenp, ppos);
+ put_uts(table, write, which);
return r;
}
-#endif /* !CONFIG_UTS_NS */
static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
int *valp,
--
1.4.2.rc3.g7e18e-dirty
This patch refactors the ipc sysctl support so that it is
simpler, more readable, and prepares for fixing the bug
with the wrong values being returned in the sys_sysctl interface.
The function proc_do_ipc_string was misnamed as it never handled
strings. It's magic of when to work with strings and when to work
with longs belonged in the sysctl table. I couldn't tell if the
code would work if you disabled the ipc namespace but it certainly
looked like it would have problems.
Signed-off-by: Eric W. Biederman <[email protected]>
---
kernel/sysctl.c | 106 +++++++++++++++++++++++++------------------------------
1 files changed, 49 insertions(+), 57 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 63db5a5..638aa14 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -91,7 +91,9 @@ #ifdef CONFIG_CHR_DEV_SG
extern int sg_big_buff;
#endif
#ifdef CONFIG_SYSVIPC
-static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp,
+static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
#endif
@@ -188,6 +190,18 @@ static void put_uts(ctl_table *table, in
up_write(&uts_sem);
}
+#ifdef CONFIG_SYSVIPC
+static void *get_ipc(ctl_table *table, int write)
+{
+ char *which = table->data;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+ which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
+ return which;
+}
+#else
+#define get_ipc(T,W) ((T)->data)
+#endif
+
/* /proc declarations: */
#ifdef CONFIG_PROC_SYSCTL
@@ -457,58 +471,58 @@ #ifdef CONFIG_SYSVIPC
{
.ctl_name = KERN_SHMMAX,
.procname = "shmmax",
- .data = NULL,
- .maxlen = sizeof (size_t),
+ .data = &init_ipc_ns.shm_ctlmax,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlmax),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_doulongvec_minmax,
},
{
.ctl_name = KERN_SHMALL,
.procname = "shmall",
- .data = NULL,
- .maxlen = sizeof (size_t),
+ .data = &init_ipc_ns.shm_ctlall,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlall),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_doulongvec_minmax,
},
{
.ctl_name = KERN_SHMMNI,
.procname = "shmmni",
- .data = NULL,
- .maxlen = sizeof (int),
+ .data = &init_ipc_ns.shm_ctlmni,
+ .maxlen = sizeof (init_ipc_ns.shm_ctlmni),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_dointvec,
},
{
.ctl_name = KERN_MSGMAX,
.procname = "msgmax",
- .data = NULL,
- .maxlen = sizeof (int),
+ .data = &init_ipc_ns.msg_ctlmax,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmax),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_dointvec,
},
{
.ctl_name = KERN_MSGMNI,
.procname = "msgmni",
- .data = NULL,
- .maxlen = sizeof (int),
+ .data = &init_ipc_ns.msg_ctlmni,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmni),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_dointvec,
},
{
.ctl_name = KERN_MSGMNB,
.procname = "msgmnb",
- .data = NULL,
- .maxlen = sizeof (int),
+ .data = &init_ipc_ns.msg_ctlmnb,
+ .maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_dointvec,
},
{
.ctl_name = KERN_SEM,
.procname = "sem",
- .data = NULL,
+ .data = &init_ipc_ns.sem_ctls,
.maxlen = 4*sizeof (int),
.mode = 0644,
- .proc_handler = &proc_do_ipc_string,
+ .proc_handler = &proc_ipc_dointvec,
},
#endif
#ifdef CONFIG_MAGIC_SYSRQ
@@ -2321,46 +2335,24 @@ int proc_dointvec_ms_jiffies(ctl_table *
}
#ifdef CONFIG_SYSVIPC
-static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp,
- void __user *buffer, size_t *lenp, loff_t *ppos)
+static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
- void *data;
- struct ipc_namespace *ns;
-
- ns = current->nsproxy->ipc_ns;
-
- switch (table->ctl_name) {
- case KERN_SHMMAX:
- data = &ns->shm_ctlmax;
- goto proc_minmax;
- case KERN_SHMALL:
- data = &ns->shm_ctlall;
- goto proc_minmax;
- case KERN_SHMMNI:
- data = &ns->shm_ctlmni;
- break;
- case KERN_MSGMAX:
- data = &ns->msg_ctlmax;
- break;
- case KERN_MSGMNI:
- data = &ns->msg_ctlmni;
- break;
- case KERN_MSGMNB:
- data = &ns->msg_ctlmnb;
- break;
- case KERN_SEM:
- data = &ns->sem_ctls;
- break;
- default:
- return -EINVAL;
- }
-
- return __do_proc_dointvec(data, table, write, filp, buffer,
+ void *which;
+ which = get_ipc(table, write);
+ return __do_proc_dointvec(which, table, write, filp, buffer,
lenp, ppos, NULL, NULL);
-proc_minmax:
- return __do_proc_doulongvec_minmax(data, table, write, filp, buffer,
+}
+
+static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
+ struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ void *which;
+ which = get_ipc(table, write);
+ return __do_proc_doulongvec_minmax(which, table, write, filp, buffer,
lenp, ppos, 1l, 1l);
}
+
#endif
static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
--
1.4.2.rc3.g7e18e-dirty
Currently there is a regression and the ipc sysctls
don't show up in the binary sysctl namespace.
This patch adds sysctl_ipc_data to read data/write from the
appropriate namespace and deliver it in the expected manner.
Signed-off-by: Eric W. Biederman <[email protected]>
---
kernel/sysctl.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 50 insertions(+), 0 deletions(-)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 638aa14..24c2ca8 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -142,6 +142,10 @@ static int sysctl_uts_string(ctl_table *
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen, void **context);
+static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen, void **context);
+
#ifdef CONFIG_PROC_SYSCTL
static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
void __user *buffer, size_t *lenp, loff_t *ppos);
@@ -475,6 +479,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.shm_ctlmax),
.mode = 0644,
.proc_handler = &proc_ipc_doulongvec_minmax,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SHMALL,
@@ -483,6 +488,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.shm_ctlall),
.mode = 0644,
.proc_handler = &proc_ipc_doulongvec_minmax,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SHMMNI,
@@ -491,6 +497,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.shm_ctlmni),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMAX,
@@ -499,6 +506,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.msg_ctlmax),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMNI,
@@ -507,6 +515,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.msg_ctlmni),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_MSGMNB,
@@ -515,6 +524,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
+ .strategy = sysctl_ipc_data,
},
{
.ctl_name = KERN_SEM,
@@ -523,6 +533,7 @@ #ifdef CONFIG_SYSVIPC
.maxlen = 4*sizeof (int),
.mode = 0644,
.proc_handler = &proc_ipc_dointvec,
+ .strategy = sysctl_ipc_data,
},
#endif
#ifdef CONFIG_MAGIC_SYSRQ
@@ -2613,6 +2624,45 @@ static int sysctl_uts_string(ctl_table *
return r;
}
+/* The generic sysctl ipc data routine. */
+static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen, void **context)
+{
+ size_t len;
+ void *data;
+
+ /* Get out of I don't have a variable */
+ if (!table->data || !table->maxlen)
+ return -ENOTDIR;
+
+ data = get_ipc(table, 1);
+ if (!data)
+ return -ENOTDIR;
+
+ if (oldval && oldlenp) {
+ if (get_user(len, oldlenp))
+ return -EFAULT;
+ if (len) {
+ if (len > table->maxlen)
+ len = table->maxlen;
+ if (copy_to_user(oldval, data, len))
+ return -EFAULT;
+ if (put_user(len, oldlenp))
+ return -EFAULT;
+ }
+ }
+
+ if (newval && newlen) {
+ if (newlen > table->maxlen)
+ newlen = table->maxlen;
+
+ if (copy_from_user(data, newval, newlen))
+ return -EFAULT;
+ }
+ return 1;
+}
+
#else /* CONFIG_SYSCTL_SYSCALL */
--
1.4.2.rc3.g7e18e-dirty
On Sun, Nov 26, 2006 at 09:59:26PM -0700, Eric W. Biederman wrote:
>
> The binary interface to the namespace sysctls was never implemented
> resulting in some really weird things if you attempted to use
> sys_sysctl to read your hostname for example.
>
> This patch series simples the code a little and implements the binary
> sysctl interface.
>
> In testing this patch series I discovered that our 32bit compatibility
> for the binary sysctl interface is imperfect. In particular
> KERN_SHMMAX and KERN_SMMALL are size_t sized quantities and are
> returned as 8 bytes on to 32bit binaries using a x86_64 kernel.
> However this has existing for a long time so it is not a new
> regression with the namespace work.
>
> Gads the whole sysctl thing needs work before it stops being easy
> to shoot yourself in the foot.
>
> Looking forward a little bit we need a better way to handle sysctls
> and namespaces as our current technique will not work for the network
> namespace. I think something based on the current overlapping sysctl
> trees will work but the proc side needs to be redone before we can
> use it.
the linux banner needs some attention too, when I get
around, I'll send a patch for that ...
best,
Herbert
> Eric
>
>
>
> _______________________________________________
> Containers mailing list
> [email protected]
> https://lists.osdl.org/mailman/listinfo/containers
Herbert Poetzl <[email protected]> writes:
> the linux banner needs some attention too, when I get
> around, I'll send a patch for that ...
In what sense?
I have trouble seeing the banner printed at bootup as being problematic.
Eric
On Mon, Nov 27, 2006 at 03:40:35PM -0700, Eric W. Biederman wrote:
> Herbert Poetzl <[email protected]> writes:
>
> > the linux banner needs some attention too, when I get
> > around, I'll send a patch for that ...
>
> In what sense?
>
> I have trouble seeing the banner printed at bootup as being problematic.
was it removed from procfs after 2.6.19-rc6
(/proc/version sorry, haven't checked yet)
best,
Herbert
> Eric
Herbert Poetzl <[email protected]> writes:
> On Mon, Nov 27, 2006 at 03:40:35PM -0700, Eric W. Biederman wrote:
>> Herbert Poetzl <[email protected]> writes:
>>
>> > the linux banner needs some attention too, when I get
>> > around, I'll send a patch for that ...
>>
>> In what sense?
>>
>> I have trouble seeing the banner printed at bootup as being problematic.
>
> was it removed from procfs after 2.6.19-rc6
> (/proc/version sorry, haven't checked yet)
I see where you are coming from. Yes that is a potential issue,
because ultimately that information is utsname information. Given
that we don't allow any of that information to be changed currently
that isn't a 2.6.19 issue.
Given that it is a don't care as long as we generate the same string
I don't see a problem with a patch to modify it, to track changes in
the current uts namespace.
Eric
On Tue, Nov 28, 2006 at 08:38:25AM -0700, Eric W. Biederman wrote:
> Herbert Poetzl <[email protected]> writes:
>
> > On Mon, Nov 27, 2006 at 03:40:35PM -0700, Eric W. Biederman wrote:
> >> Herbert Poetzl <[email protected]> writes:
> >>
> >> > the linux banner needs some attention too, when I get
> >> > around, I'll send a patch for that ...
> >>
> >> In what sense?
> >>
> >> I have trouble seeing the banner printed at bootup as being problematic.
> >
> > was it removed from procfs after 2.6.19-rc6
> > (/proc/version sorry, haven't checked yet)
>
> I see where you are coming from. Yes that is a potential issue,
> because ultimately that information is utsname information.
> Given that we don't allow any of that information to be changed
> currently that isn't a 2.6.19 issue.
>
> Given that it is a don't care as long as we generate the same string
> I don't see a problem with a patch to modify it, to track changes in
> the current uts namespace.
thank you very much,
Herbert
> Eric
Quoting Eric W. Biederman ([email protected]):
> This patch refactors the ipc sysctl support so that it is
> simpler, more readable, and prepares for fixing the bug
> with the wrong values being returned in the sys_sysctl interface.
>
> The function proc_do_ipc_string was misnamed as it never handled
> strings. It's magic of when to work with strings and when to work
> with longs belonged in the sysctl table. I couldn't tell if the
> code would work if you disabled the ipc namespace but it certainly
> looked like it would have problems.
>
> Signed-off-by: Eric W. Biederman <[email protected]>
Hi,
A little belated (sorry), but the only comment I have right now on the
patchset is that the get_ipc() seems like it shouldn't take the write
arg. Perhaps if consistency is the concern, get_uts() should simply
be called get_uts_locked(table, need_write) ? This also avoids the
mysterious '1' argument in the next patch at get_ipc(table, 1);
Oh, I lied, one more comment. It seems worth a comment at the top of
get_uts() and get_ipc() explaining that table->data points to
init_uts->data and that's why the 'which = which - init_uts + uts'
works.
thanks,
-serge
utsname information is shown in the linux banner, which
also is used for /proc/version (which can have different
utsname values inside a uts namespaces). this patch
makes the varying data arguments and changes the string
to a format string, using those arguments.
best,
Herbert
Signed-off-by: Herbert Poetzl <[email protected]>
--- linux-2.6.19/fs/proc/proc_misc.c 2006-11-30 21:19:28 +0100
+++ linux-2.6.19/fs/proc/proc_misc.c 2006-12-04 07:16:28 +0100
@@ -252,8 +252,8 @@ static int version_read_proc(char *page,
{
int len;
- strcpy(page, linux_banner);
- len = strlen(page);
+ len = sprintf(page, linux_banner,
+ utsname()->release, utsname()->version);
return proc_calc_metrics(page, start, off, count, eof, len);
}
--- linux-2.6.19/init/main.c 2006-11-30 21:19:43 +0100
+++ linux-2.6.19/init/main.c 2006-12-04 07:18:44 +0100
@@ -501,7 +501,7 @@ asmlinkage void __init start_kernel(void
boot_cpu_init();
page_address_init();
printk(KERN_NOTICE);
- printk(linux_banner);
+ printk(linux_banner, UTS_RELEASE, UTS_VERSION);
setup_arch(&command_line);
unwind_setup();
setup_per_cpu_areas();
--- linux-2.6.19/init/version.c 2006-11-30 21:19:43 +0100
+++ linux-2.6.19/init/version.c 2006-12-04 07:14:19 +0100
@@ -35,5 +35,6 @@ struct uts_namespace init_uts_ns = {
EXPORT_SYMBOL_GPL(init_uts_ns);
const char linux_banner[] =
- "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"
- LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";
+ "Linux version %s (" LINUX_COMPILE_BY "@"
+ LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") %s\n";
+
On Mon, Dec 04, 2006 at 11:32:48PM +0100, Herbert Poetzl wrote:
>
> utsname information is shown in the linux banner, which
> also is used for /proc/version (which can have different
> utsname values inside a uts namespaces). this patch
> makes the varying data arguments and changes the string
> to a format string, using those arguments.
>
> best,
> Herbert
d'oh! just figured I lost the two new includes required
in main.c, will send an updated version shortly
best,
Herbert
> Signed-off-by: Herbert Poetzl <[email protected]>
>
> --- linux-2.6.19/fs/proc/proc_misc.c 2006-11-30 21:19:28 +0100
> +++ linux-2.6.19/fs/proc/proc_misc.c 2006-12-04 07:16:28 +0100
> @@ -252,8 +252,8 @@ static int version_read_proc(char *page,
> {
> int len;
>
> - strcpy(page, linux_banner);
> - len = strlen(page);
> + len = sprintf(page, linux_banner,
> + utsname()->release, utsname()->version);
> return proc_calc_metrics(page, start, off, count, eof, len);
> }
>
> --- linux-2.6.19/init/main.c 2006-11-30 21:19:43 +0100
> +++ linux-2.6.19/init/main.c 2006-12-04 07:18:44 +0100
> @@ -501,7 +501,7 @@ asmlinkage void __init start_kernel(void
> boot_cpu_init();
> page_address_init();
> printk(KERN_NOTICE);
> - printk(linux_banner);
> + printk(linux_banner, UTS_RELEASE, UTS_VERSION);
> setup_arch(&command_line);
> unwind_setup();
> setup_per_cpu_areas();
> --- linux-2.6.19/init/version.c 2006-11-30 21:19:43 +0100
> +++ linux-2.6.19/init/version.c 2006-12-04 07:14:19 +0100
> @@ -35,5 +35,6 @@ struct uts_namespace init_uts_ns = {
> EXPORT_SYMBOL_GPL(init_uts_ns);
>
> const char linux_banner[] =
> - "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"
> - LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";
> + "Linux version %s (" LINUX_COMPILE_BY "@"
> + LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") %s\n";
> +
> -
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On Tue, Dec 05, 2006 at 06:24:09PM +0100, Herbert Poetzl wrote:
> On Mon, Dec 04, 2006 at 11:32:48PM +0100, Herbert Poetzl wrote:
> >
> > utsname information is shown in the linux banner, which
> > also is used for /proc/version (which can have different
> > utsname values inside a uts namespaces). this patch
> > makes the varying data arguments and changes the string
> > to a format string, using those arguments.
> >
> > best,
> > Herbert
>
> d'oh! just figured I lost the two new includes required
> in main.c, will send an updated version shortly
okay, here is the complete and tested version ...
Signed-off-by: Herbert Poetzl <[email protected]>
--- linux-2.6.19/fs/proc/proc_misc.c 2006-11-30 21:19:28 +0100
+++ linux-2.6.19-banner/fs/proc/proc_misc.c 2006-12-06 07:10:41 +0100
@@ -252,8 +252,8 @@ static int version_read_proc(char *page,
{
int len;
- strcpy(page, linux_banner);
- len = strlen(page);
+ len = sprintf(page, linux_banner,
+ utsname()->release, utsname()->version);
return proc_calc_metrics(page, start, off, count, eof, len);
}
--- linux-2.6.19/init/Makefile 2006-09-20 16:58:44 +0200
+++ linux-2.6.19-banner/init/Makefile 2006-12-06 07:10:41 +0100
@@ -15,6 +15,7 @@ clean-files := ../include/linux/compile.
# dependencies on generated files need to be listed explicitly
+$(obj)/main.o: include/linux/compile.h
$(obj)/version.o: include/linux/compile.h
# compile.h changes depending on hostname, generation number, etc,
--- linux-2.6.19/init/main.c 2006-11-30 21:19:43 +0100
+++ linux-2.6.19-banner/init/main.c 2006-12-06 07:10:41 +0100
@@ -49,6 +49,8 @@
#include <linux/buffer_head.h>
#include <linux/debug_locks.h>
#include <linux/lockdep.h>
+#include <linux/utsrelease.h>
+#include <linux/compile.h>
#include <asm/io.h>
#include <asm/bugs.h>
@@ -501,7 +503,7 @@ asmlinkage void __init start_kernel(void
boot_cpu_init();
page_address_init();
printk(KERN_NOTICE);
- printk(linux_banner);
+ printk(linux_banner, UTS_RELEASE, UTS_VERSION);
setup_arch(&command_line);
unwind_setup();
setup_per_cpu_areas();
--- linux-2.6.19/init/version.c 2006-11-30 21:19:43 +0100
+++ linux-2.6.19-banner/init/version.c 2006-12-06 07:10:41 +0100
@@ -35,5 +35,6 @@ struct uts_namespace init_uts_ns = {
EXPORT_SYMBOL_GPL(init_uts_ns);
const char linux_banner[] =
- "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"
- LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";
+ "Linux version %s (" LINUX_COMPILE_BY "@"
+ LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") %s\n";
+