android/android_kernel_samsung_sm8650
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Revert "dm: fix a race condition in retrieve_deps"

Browse Source 
This reverts commit dbf1a71985 which is
commit f6007dce0cd35d634d9be91ef3515a6385dcee16 upstream.

It breaks the Android ABI and can be brought back later in an abi-safe
way if needed.

Bug: 161946584
Change-Id: Ief37eab88188180ba9884987d9731b10d1527051
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Greg Kroah-Hartman 2023-11-01 07:15:44 +00:00
parent d07ffd5565
commit 7bcb060a61
3 changed files with 9 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/md/dm-core.h
View File

@ -214,7 +214,6 @@ struct dm_table {
/* a list of devices used by this table */
struct list_head devices;
struct rw_semaphore devices_lock;
/* events get handed up using this callback */
void (*event_fn)(void *);

7
drivers/md/dm-ioctl.c
View File

@ -1566,8 +1566,6 @@ static void retrieve_deps(struct dm_table *table,
struct dm_dev_internal *dd;
struct dm_target_deps *deps;
down_read(&table->devices_lock);
deps = get_result_buffer(param, param_size, &len);
/*
@ -1582,7 +1580,7 @@ static void retrieve_deps(struct dm_table *table,
needed = struct_size(deps, dev, count);
if (len < needed) {
param->flags |= DM_BUFFER_FULL_FLAG;
goto out;
return;
}
/*
@ -1594,9 +1592,6 @@ static void retrieve_deps(struct dm_table *table,
deps->dev[count++] = huge_encode_dev(dd->dm_dev->bdev->bd_dev);
param->data_size = param->data_start + needed;
out:
up_read(&table->devices_lock);
}
static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size)

32
drivers/md/dm-table.c
View File

@ -134,7 +134,6 @@ int dm_table_create(struct dm_table **result, fmode_t mode,
return -ENOMEM;
INIT_LIST_HEAD(&t->devices);
init_rwsem(&t->devices_lock);
if (!num_targets)
num_targets = KEYS_PER_NODE;
@ -363,19 +362,15 @@ int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
return -ENODEV;
}
down_write(&t->devices_lock);
dd = find_device(&t->devices, dev);
if (!dd) {
dd = kmalloc(sizeof(*dd), GFP_KERNEL);
if (!dd) {
r = -ENOMEM;
goto unlock_ret_r;
}
if (!dd)
return -ENOMEM;
if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) {
kfree(dd);
goto unlock_ret_r;
return r;
}
refcount_set(&dd->count, 1);
@ -385,17 +380,12 @@ int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
} else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) {
r = upgrade_mode(dd, mode, t->md);
if (r)
goto unlock_ret_r;
return r;
}
refcount_inc(&dd->count);
out:
up_write(&t->devices_lock);
*result = dd->dm_dev;
return 0;
unlock_ret_r:
up_write(&t->devices_lock);
return r;
}
EXPORT_SYMBOL(dm_get_device);
@ -431,12 +421,9 @@ static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
void dm_put_device(struct dm_target *ti, struct dm_dev *d)
{
int found = 0;
struct dm_table *t = ti->table;
struct list_head *devices = &t->devices;
struct list_head *devices = &ti->table->devices;
struct dm_dev_internal *dd;
down_write(&t->devices_lock);
list_for_each_entry(dd, devices, list) {
if (dd->dm_dev == d) {
found = 1;
@ -445,17 +432,14 @@ void dm_put_device(struct dm_target *ti, struct dm_dev *d)
}
if (!found) {
DMERR("%s: device %s not in table devices list",
dm_device_name(t->md), d->name);
goto unlock_ret;
dm_device_name(ti->table->md), d->name);
return;
}
if (refcount_dec_and_test(&dd->count)) {
dm_put_table_device(t->md, d);
dm_put_table_device(ti->table->md, d);
list_del(&dd->list);
kfree(dd);
}
unlock_ret:
up_write(&t->devices_lock);
}
EXPORT_SYMBOL(dm_put_device);