[Xenial][SRU][PATCH 2/2] btrfs: merge btrfs_find_device and find_device
Connor Kuehl
connor.kuehl at canonical.com
Tue Dec 10 00:48:20 UTC 2019
From: Anand Jain <anand.jain at oracle.com>
CVE-2019-18885
Both btrfs_find_device() and find_device() does the same thing except
that the latter does not take the seed device onto account in the device
scanning context. We can merge them.
Signed-off-by: Anand Jain <anand.jain at oracle.com>
Reviewed-by: David Sterba <dsterba at suse.com>
Signed-off-by: David Sterba <dsterba at suse.com>
(backported from commit 09ba3bc9dd150457c506e4661380a6183af651c1)
[ Connor Kuehl: these functions still pass the root pointer as an
argument instead of a `struct btrfs_fs_info *` so pass in the
fs_devices object by accessing it through the root pointer. ]
Signed-off-by: Connor Kuehl <connor.kuehl at canonical.com>
---
fs/btrfs/dev-replace.c | 8 +++----
fs/btrfs/ioctl.c | 5 +++--
fs/btrfs/scrub.c | 4 ++--
fs/btrfs/volumes.c | 47 ++++++++++++++++++++++++++++--------------
fs/btrfs/volumes.h | 2 +-
5 files changed, 42 insertions(+), 24 deletions(-)
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 4b85c42ee2f5..1c15c49235fe 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -136,10 +136,10 @@ no_valid_dev_replace_entry_found:
case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
dev_replace->srcdev = btrfs_find_device(fs_info->fs_devices,
- src_devid, NULL, NULL);
+ src_devid, NULL, NULL, true);
dev_replace->tgtdev = btrfs_find_device(fs_info->fs_devices,
BTRFS_DEV_REPLACE_DEVID,
- NULL, NULL);
+ NULL, NULL, true);
/*
* allow 'btrfs dev replace_cancel' if src/tgt device is
* missing
@@ -647,8 +647,8 @@ static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
if (srcdevid) {
ret = 0;
- *device = btrfs_find_device(root->fs_info, srcdevid, NULL,
- NULL);
+ *device = btrfs_find_device(root->fs_info->fs_devices, srcdevid,
+ NULL, NULL, false);
if (!*device)
ret = -ENOENT;
} else {
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index d38b8e6fdb6e..d7397be1fb83 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1524,7 +1524,7 @@ static noinline int btrfs_ioctl_resize(struct file *file,
btrfs_info(root->fs_info, "resizing devid %llu", devid);
}
- device = btrfs_find_device(root->fs_info->fs_devices, devid, NULL, NULL);
+ device = btrfs_find_device(root->fs_info->fs_devices, devid, NULL, NULL, true);
if (!device) {
btrfs_info(root->fs_info, "resizer unable to find device %llu",
devid);
@@ -2766,7 +2766,8 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
s_uuid = di_args->uuid;
mutex_lock(&fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_devices, di_args->devid, s_uuid, NULL);
+ dev = btrfs_find_device(fs_devices, di_args->devid, s_uuid,
+ NULL, true);
if (!dev) {
ret = -ENODEV;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 866a6c579099..099047e133d7 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3836,7 +3836,7 @@ int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
mutex_lock(&fs_info->fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL);
+ dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
if (!dev || (dev->missing && !is_dev_replace)) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
return -ENODEV;
@@ -4005,7 +4005,7 @@ int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
struct scrub_ctx *sctx = NULL;
mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
- dev = btrfs_find_device(root->fs_info->fs_devices, devid, NULL, NULL);
+ dev = btrfs_find_device(root->fs_info->fs_devices, devid, NULL, NULL, true);
if (dev)
sctx = dev->scrub_device;
if (sctx)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 203c8eba5a89..59472e01098e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -608,8 +608,8 @@ static noinline int device_list_add(const char *path,
device = NULL;
} else {
- device = __find_device(&fs_devices->devices, devid,
- disk_super->dev_item.uuid);
+ device = btrfs_find_device(fs_devices, devid,
+ disk_super->dev_item.uuid, NULL, false);
}
if (!device) {
@@ -1779,7 +1779,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
devid = btrfs_stack_device_id(&disk_super->dev_item);
dev_uuid = disk_super->dev_item.uuid;
device = btrfs_find_device(root->fs_info->fs_devices, devid, dev_uuid,
- disk_super->fsid);
+ disk_super->fsid, true);
if (!device) {
ret = -ENOENT;
goto error_brelse;
@@ -2063,7 +2063,7 @@ static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
devid = btrfs_stack_device_id(&disk_super->dev_item);
dev_uuid = disk_super->dev_item.uuid;
*device = btrfs_find_device(root->fs_info->fs_devices, devid, dev_uuid,
- disk_super->fsid);
+ disk_super->fsid, true);
brelse(bh);
if (!*device)
ret = -ENOENT;
@@ -2219,9 +2219,9 @@ next_slot:
read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
- BTRFS_UUID_SIZE);
+ BTRFS_FSID_SIZE);
device = btrfs_find_device(root->fs_info->fs_devices, devid, dev_uuid,
- fs_uuid);
+ fs_uuid, true);
BUG_ON(!device); /* Logic error */
if (device->fs_devices->seeding) {
@@ -6117,19 +6117,36 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
return 0;
}
+/*
+ * Find a device specified by @devid or @uuid in the list of @fs_devices, or
+ * return NULL.
+ *
+ * If devid and uuid are both specified, the match must be exact, otherwise
+ * only devid is used.
+ *
+ * If @seed is true, traverse through the seed devices.
+ */
struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
- u64 devid, u8 *uuid, u8 *fsid)
+ u64 devid, u8 *uuid, u8 *fsid,
+ bool seed)
{
struct btrfs_device *device;
while (fs_devices) {
if (!fsid ||
- !memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
- device = __find_device(&fs_devices->devices, devid, uuid);
- if (device)
- return device;
+ !memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE)) {
+ list_for_each_entry(device, &fs_devices->devices,
+ dev_list) {
+ if (device->devid == devid &&
+ (!uuid || memcmp(device->uuid, uuid,
+ BTRFS_UUID_SIZE) == 0))
+ return device;
+ }
}
- fs_devices = fs_devices->seed;
+ if (seed)
+ fs_devices = fs_devices->seed;
+ else
+ return NULL;
}
return NULL;
}
@@ -6369,7 +6386,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
btrfs_stripe_dev_uuid_nr(chunk, i),
BTRFS_UUID_SIZE);
map->stripes[i].dev = btrfs_find_device(root->fs_info->fs_devices,
- devid, uuid, NULL);
+ devid, uuid, NULL, true);
if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
free_extent_map(em);
return -EIO;
@@ -6498,7 +6515,7 @@ static int read_one_dev(struct btrfs_root *root,
return PTR_ERR(fs_devices);
}
- device = btrfs_find_device(fs_devices, devid, dev_uuid, fs_uuid);
+ device = btrfs_find_device(fs_devices, devid, dev_uuid, fs_uuid, true);
if (!device) {
if (!btrfs_test_opt(root, DEGRADED))
return -EIO;
@@ -6961,7 +6978,7 @@ int btrfs_get_dev_stats(struct btrfs_root *root,
int i;
mutex_lock(&fs_devices->device_list_mutex);
- dev = btrfs_find_device(fs_devices, stats->devid, NULL, NULL);
+ dev = btrfs_find_device(fs_devices, stats->devid, NULL, NULL, true);
mutex_unlock(&fs_devices->device_list_mutex);
if (!dev) {
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index e53f273595b1..185787fd4b91 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -464,7 +464,7 @@ int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
int btrfs_grow_device(struct btrfs_trans_handle *trans,
struct btrfs_device *device, u64 new_size);
struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices,
- u64 devid, u8 *uuid, u8 *fsid);
+ u64 devid, u8 *uuid, u8 *fsid, bool seed);
int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
int btrfs_init_new_device(struct btrfs_root *root, char *path);
int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
--
2.17.1
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