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
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
