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-rw-r--r--drivers/md/dm-core.h1
-rw-r--r--drivers/md/dm-ioctl.c37
-rw-r--r--drivers/md/dm.c10
-rw-r--r--include/uapi/linux/dm-ioctl.h4
4 files changed, 35 insertions, 17 deletions
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
index 24eddbdf2ab4..203144762f36 100644
--- a/drivers/md/dm-core.h
+++ b/drivers/md/dm-core.h
@@ -149,5 +149,6 @@ static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen
extern atomic_t dm_global_event_nr;
extern wait_queue_head_t dm_global_eventq;
+void dm_issue_global_event(void);
#endif
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 8756a6850431..e52676fa9832 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -477,9 +477,13 @@ static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_si
* Round up the ptr to an 8-byte boundary.
*/
#define ALIGN_MASK 7
+static inline size_t align_val(size_t val)
+{
+ return (val + ALIGN_MASK) & ~ALIGN_MASK;
+}
static inline void *align_ptr(void *ptr)
{
- return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
+ return (void *)align_val((size_t)ptr);
}
/*
@@ -505,7 +509,7 @@ static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_
struct hash_cell *hc;
size_t len, needed = 0;
struct gendisk *disk;
- struct dm_name_list *nl, *old_nl = NULL;
+ struct dm_name_list *orig_nl, *nl, *old_nl = NULL;
uint32_t *event_nr;
down_write(&_hash_lock);
@@ -516,17 +520,15 @@ static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_
*/
for (i = 0; i < NUM_BUCKETS; i++) {
list_for_each_entry (hc, _name_buckets + i, name_list) {
- needed += sizeof(struct dm_name_list);
- needed += strlen(hc->name) + 1;
- needed += ALIGN_MASK;
- needed += (sizeof(uint32_t) + ALIGN_MASK) & ~ALIGN_MASK;
+ needed += align_val(offsetof(struct dm_name_list, name) + strlen(hc->name) + 1);
+ needed += align_val(sizeof(uint32_t));
}
}
/*
* Grab our output buffer.
*/
- nl = get_result_buffer(param, param_size, &len);
+ nl = orig_nl = get_result_buffer(param, param_size, &len);
if (len < needed) {
param->flags |= DM_BUFFER_FULL_FLAG;
goto out;
@@ -549,11 +551,16 @@ static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_
strcpy(nl->name, hc->name);
old_nl = nl;
- event_nr = align_ptr(((void *) (nl + 1)) + strlen(hc->name) + 1);
+ event_nr = align_ptr(nl->name + strlen(hc->name) + 1);
*event_nr = dm_get_event_nr(hc->md);
nl = align_ptr(event_nr + 1);
}
}
+ /*
+ * If mismatch happens, security may be compromised due to buffer
+ * overflow, so it's better to crash.
+ */
+ BUG_ON((char *)nl - (char *)orig_nl != needed);
out:
up_write(&_hash_lock);
@@ -1621,7 +1628,8 @@ static int target_message(struct file *filp, struct dm_ioctl *param, size_t para
* which has a variable size, is not used by the function processing
* the ioctl.
*/
-#define IOCTL_FLAGS_NO_PARAMS 1
+#define IOCTL_FLAGS_NO_PARAMS 1
+#define IOCTL_FLAGS_ISSUE_GLOBAL_EVENT 2
/*-----------------------------------------------------------------
* Implementation of open/close/ioctl on the special char
@@ -1635,12 +1643,12 @@ static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
ioctl_fn fn;
} _ioctls[] = {
{DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
- {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS, remove_all},
+ {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, remove_all},
{DM_LIST_DEVICES_CMD, 0, list_devices},
- {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_create},
- {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_remove},
- {DM_DEV_RENAME_CMD, 0, dev_rename},
+ {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_create},
+ {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_remove},
+ {DM_DEV_RENAME_CMD, IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_rename},
{DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend},
{DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
{DM_DEV_WAIT_CMD, 0, dev_wait},
@@ -1869,6 +1877,9 @@ static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *us
unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
+ if (!r && ioctl_flags & IOCTL_FLAGS_ISSUE_GLOBAL_EVENT)
+ dm_issue_global_event();
+
/*
* Copy the results back to userland.
*/
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 6e54145969c5..4be85324f44d 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -52,6 +52,12 @@ static struct workqueue_struct *deferred_remove_workqueue;
atomic_t dm_global_event_nr = ATOMIC_INIT(0);
DECLARE_WAIT_QUEUE_HEAD(dm_global_eventq);
+void dm_issue_global_event(void)
+{
+ atomic_inc(&dm_global_event_nr);
+ wake_up(&dm_global_eventq);
+}
+
/*
* One of these is allocated per bio.
*/
@@ -1865,9 +1871,8 @@ static void event_callback(void *context)
dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj);
atomic_inc(&md->event_nr);
- atomic_inc(&dm_global_event_nr);
wake_up(&md->eventq);
- wake_up(&dm_global_eventq);
+ dm_issue_global_event();
}
/*
@@ -2283,6 +2288,7 @@ struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table)
}
map = __bind(md, table, &limits);
+ dm_issue_global_event();
out:
mutex_unlock(&md->suspend_lock);
diff --git a/include/uapi/linux/dm-ioctl.h b/include/uapi/linux/dm-ioctl.h
index 412c06a624c8..ccaea525340b 100644
--- a/include/uapi/linux/dm-ioctl.h
+++ b/include/uapi/linux/dm-ioctl.h
@@ -269,9 +269,9 @@ enum {
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
-#define DM_VERSION_MINOR 36
+#define DM_VERSION_MINOR 37
#define DM_VERSION_PATCHLEVEL 0
-#define DM_VERSION_EXTRA "-ioctl (2017-06-09)"
+#define DM_VERSION_EXTRA "-ioctl (2017-09-20)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */