diff options
| author | David Howells <dhowells@redhat.com> | 2024-01-19 23:49:34 +0300 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2024-01-23 01:25:15 +0300 |
| commit | c3d6569a43322f371e7ba0ad386112723757ac8f (patch) | |
| tree | a5e95c94000f9ddd3c19dc9fd8db9214e095022f /fs/cachefiles | |
| parent | 843609df0be792991b3c4a720d6be4828d48dec4 (diff) | |
| download | linux-c3d6569a43322f371e7ba0ad386112723757ac8f.tar.xz | |
cachefiles, erofs: Fix NULL deref in when cachefiles is not doing ondemand-mode
cachefiles_ondemand_init_object() as called from cachefiles_open_file() and
cachefiles_create_tmpfile() does not check if object->ondemand is set
before dereferencing it, leading to an oops something like:
RIP: 0010:cachefiles_ondemand_init_object+0x9/0x41
...
Call Trace:
<TASK>
cachefiles_open_file+0xc9/0x187
cachefiles_lookup_cookie+0x122/0x2be
fscache_cookie_state_machine+0xbe/0x32b
fscache_cookie_worker+0x1f/0x2d
process_one_work+0x136/0x208
process_scheduled_works+0x3a/0x41
worker_thread+0x1a2/0x1f6
kthread+0xca/0xd2
ret_from_fork+0x21/0x33
Fix this by making cachefiles_ondemand_init_object() return immediately if
cachefiles->ondemand is NULL.
Fixes: 3c5ecfe16e76 ("cachefiles: extract ondemand info field from cachefiles_object")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Gao Xiang <xiang@kernel.org>
cc: Chao Yu <chao@kernel.org>
cc: Yue Hu <huyue2@coolpad.com>
cc: Jeffle Xu <jefflexu@linux.alibaba.com>
cc: linux-erofs@lists.ozlabs.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Diffstat (limited to 'fs/cachefiles')
| -rw-r--r-- | fs/cachefiles/ondemand.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index 5fd74ec60bef..4ba42f1fa3b4 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -539,6 +539,9 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object) struct fscache_volume *volume = object->volume->vcookie; size_t volume_key_size, cookie_key_size, data_len; + if (!object->ondemand) + return 0; + /* * CacheFiles will firstly check the cache file under the root cache * directory. If the coherency check failed, it will fallback to |