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path: root/drivers/md/dm-ioctl.c
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Diffstat (limited to 'drivers/md/dm-ioctl.c')
-rw-r--r--drivers/md/dm-ioctl.c166
1 files changed, 119 insertions, 47 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 0666b5d14b8..aa04f022464 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1067,6 +1067,7 @@ static void retrieve_status(struct dm_table *table,
num_targets = dm_table_get_num_targets(table);
for (i = 0; i < num_targets; i++) {
struct dm_target *ti = dm_table_get_target(table, i);
+ size_t l;
remaining = len - (outptr - outbuf);
if (remaining <= sizeof(struct dm_target_spec)) {
@@ -1093,14 +1094,17 @@ static void retrieve_status(struct dm_table *table,
if (ti->type->status) {
if (param->flags & DM_NOFLUSH_FLAG)
status_flags |= DM_STATUS_NOFLUSH_FLAG;
- if (ti->type->status(ti, type, status_flags, outptr, remaining)) {
- param->flags |= DM_BUFFER_FULL_FLAG;
- break;
- }
+ ti->type->status(ti, type, status_flags, outptr, remaining);
} else
outptr[0] = '\0';
- outptr += strlen(outptr) + 1;
+ l = strlen(outptr) + 1;
+ if (l == remaining) {
+ param->flags |= DM_BUFFER_FULL_FLAG;
+ break;
+ }
+
+ outptr += l;
used = param->data_start + (outptr - outbuf);
outptr = align_ptr(outptr);
@@ -1410,6 +1414,22 @@ static int table_status(struct dm_ioctl *param, size_t param_size)
return 0;
}
+static bool buffer_test_overflow(char *result, unsigned maxlen)
+{
+ return !maxlen || strlen(result) + 1 >= maxlen;
+}
+
+/*
+ * Process device-mapper dependent messages.
+ * Returns a number <= 1 if message was processed by device mapper.
+ * Returns 2 if message should be delivered to the target.
+ */
+static int message_for_md(struct mapped_device *md, unsigned argc, char **argv,
+ char *result, unsigned maxlen)
+{
+ return 2;
+}
+
/*
* Pass a message to the target that's at the supplied device offset.
*/
@@ -1421,6 +1441,8 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
struct dm_table *table;
struct dm_target *ti;
struct dm_target_msg *tmsg = (void *) param + param->data_start;
+ size_t maxlen;
+ char *result = get_result_buffer(param, param_size, &maxlen);
md = find_device(param);
if (!md)
@@ -1444,6 +1466,10 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
goto out_argv;
}
+ r = message_for_md(md, argc, argv, result, maxlen);
+ if (r <= 1)
+ goto out_argv;
+
table = dm_get_live_table(md);
if (!table)
goto out_argv;
@@ -1469,44 +1495,68 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
out_argv:
kfree(argv);
out:
- param->data_size = 0;
+ if (r >= 0)
+ __dev_status(md, param);
+
+ if (r == 1) {
+ param->flags |= DM_DATA_OUT_FLAG;
+ if (buffer_test_overflow(result, maxlen))
+ param->flags |= DM_BUFFER_FULL_FLAG;
+ else
+ param->data_size = param->data_start + strlen(result) + 1;
+ r = 0;
+ }
+
dm_put(md);
return r;
}
+/*
+ * The ioctl parameter block consists of two parts, a dm_ioctl struct
+ * followed by a data buffer. This flag is set if the second part,
+ * which has a variable size, is not used by the function processing
+ * the ioctl.
+ */
+#define IOCTL_FLAGS_NO_PARAMS 1
+
/*-----------------------------------------------------------------
* Implementation of open/close/ioctl on the special char
* device.
*---------------------------------------------------------------*/
-static ioctl_fn lookup_ioctl(unsigned int cmd)
+static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
{
static struct {
int cmd;
+ int flags;
ioctl_fn fn;
} _ioctls[] = {
- {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */
- {DM_REMOVE_ALL_CMD, remove_all},
- {DM_LIST_DEVICES_CMD, list_devices},
-
- {DM_DEV_CREATE_CMD, dev_create},
- {DM_DEV_REMOVE_CMD, dev_remove},
- {DM_DEV_RENAME_CMD, dev_rename},
- {DM_DEV_SUSPEND_CMD, dev_suspend},
- {DM_DEV_STATUS_CMD, dev_status},
- {DM_DEV_WAIT_CMD, dev_wait},
-
- {DM_TABLE_LOAD_CMD, table_load},
- {DM_TABLE_CLEAR_CMD, table_clear},
- {DM_TABLE_DEPS_CMD, table_deps},
- {DM_TABLE_STATUS_CMD, table_status},
-
- {DM_LIST_VERSIONS_CMD, list_versions},
-
- {DM_TARGET_MSG_CMD, target_message},
- {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
+ {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
+ {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS, 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_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},
+
+ {DM_TABLE_LOAD_CMD, 0, table_load},
+ {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear},
+ {DM_TABLE_DEPS_CMD, 0, table_deps},
+ {DM_TABLE_STATUS_CMD, 0, table_status},
+
+ {DM_LIST_VERSIONS_CMD, 0, list_versions},
+
+ {DM_TARGET_MSG_CMD, 0, target_message},
+ {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry}
};
- return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;
+ if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
+ return NULL;
+
+ *ioctl_flags = _ioctls[cmd].flags;
+ return _ioctls[cmd].fn;
}
/*
@@ -1543,7 +1593,8 @@ static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
return r;
}
-#define DM_PARAMS_VMALLOC 0x0001 /* Params alloced with vmalloc not kmalloc */
+#define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */
+#define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */
#define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
@@ -1551,66 +1602,80 @@ static void free_params(struct dm_ioctl *param, size_t param_size, int param_fla
if (param_flags & DM_WIPE_BUFFER)
memset(param, 0, param_size);
+ if (param_flags & DM_PARAMS_KMALLOC)
+ kfree(param);
if (param_flags & DM_PARAMS_VMALLOC)
vfree(param);
- else
- kfree(param);
}
-static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param, int *param_flags)
+static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
+ int ioctl_flags,
+ struct dm_ioctl **param, int *param_flags)
{
- struct dm_ioctl tmp, *dmi;
+ struct dm_ioctl *dmi;
int secure_data;
+ const size_t minimum_data_size = sizeof(*param_kernel) - sizeof(param_kernel->data);
- if (copy_from_user(&tmp, user, sizeof(tmp) - sizeof(tmp.data)))
+ if (copy_from_user(param_kernel, user, minimum_data_size))
return -EFAULT;
- if (tmp.data_size < (sizeof(tmp) - sizeof(tmp.data)))
+ if (param_kernel->data_size < minimum_data_size)
return -EINVAL;
- secure_data = tmp.flags & DM_SECURE_DATA_FLAG;
+ secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
*param_flags = secure_data ? DM_WIPE_BUFFER : 0;
+ if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) {
+ dmi = param_kernel;
+ dmi->data_size = minimum_data_size;
+ goto data_copied;
+ }
+
/*
* Try to avoid low memory issues when a device is suspended.
* Use kmalloc() rather than vmalloc() when we can.
*/
dmi = NULL;
- if (tmp.data_size <= KMALLOC_MAX_SIZE)
- dmi = kmalloc(tmp.data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
+ if (param_kernel->data_size <= KMALLOC_MAX_SIZE) {
+ dmi = kmalloc(param_kernel->data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
+ if (dmi)
+ *param_flags |= DM_PARAMS_KMALLOC;
+ }
if (!dmi) {
- dmi = __vmalloc(tmp.data_size, GFP_NOIO | __GFP_REPEAT | __GFP_HIGH, PAGE_KERNEL);
- *param_flags |= DM_PARAMS_VMALLOC;
+ dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_REPEAT | __GFP_HIGH, PAGE_KERNEL);
+ if (dmi)
+ *param_flags |= DM_PARAMS_VMALLOC;
}
if (!dmi) {
- if (secure_data && clear_user(user, tmp.data_size))
+ if (secure_data && clear_user(user, param_kernel->data_size))
return -EFAULT;
return -ENOMEM;
}
- if (copy_from_user(dmi, user, tmp.data_size))
+ if (copy_from_user(dmi, user, param_kernel->data_size))
goto bad;
+data_copied:
/*
* Abort if something changed the ioctl data while it was being copied.
*/
- if (dmi->data_size != tmp.data_size) {
+ if (dmi->data_size != param_kernel->data_size) {
DMERR("rejecting ioctl: data size modified while processing parameters");
goto bad;
}
/* Wipe the user buffer so we do not return it to userspace */
- if (secure_data && clear_user(user, tmp.data_size))
+ if (secure_data && clear_user(user, param_kernel->data_size))
goto bad;
*param = dmi;
return 0;
bad:
- free_params(dmi, tmp.data_size, *param_flags);
+ free_params(dmi, param_kernel->data_size, *param_flags);
return -EFAULT;
}
@@ -1621,6 +1686,7 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
param->flags &= ~DM_BUFFER_FULL_FLAG;
param->flags &= ~DM_UEVENT_GENERATED_FLAG;
param->flags &= ~DM_SECURE_DATA_FLAG;
+ param->flags &= ~DM_DATA_OUT_FLAG;
/* Ignores parameters */
if (cmd == DM_REMOVE_ALL_CMD ||
@@ -1648,11 +1714,13 @@ static int validate_params(uint cmd, struct dm_ioctl *param)
static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
{
int r = 0;
+ int ioctl_flags;
int param_flags;
unsigned int cmd;
struct dm_ioctl *uninitialized_var(param);
ioctl_fn fn = NULL;
size_t input_param_size;
+ struct dm_ioctl param_kernel;
/* only root can play with this */
if (!capable(CAP_SYS_ADMIN))
@@ -1677,7 +1745,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
if (cmd == DM_VERSION_CMD)
return 0;
- fn = lookup_ioctl(cmd);
+ fn = lookup_ioctl(cmd, &ioctl_flags);
if (!fn) {
DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
return -ENOTTY;
@@ -1686,7 +1754,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
/*
* Copy the parameters into kernel space.
*/
- r = copy_params(user, &param, &param_flags);
+ r = copy_params(user, &param_kernel, ioctl_flags, &param, &param_flags);
if (r)
return r;
@@ -1699,6 +1767,10 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
param->data_size = sizeof(*param);
r = fn(param, input_param_size);
+ if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
+ unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
+ DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
+
/*
* Copy the results back to userland.
*/
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-30 21:57:23 +0000