David Howells 9afc658ce7 cachefiles, erofs: Fix NULL deref in when cachefiles is not doing ondemand-mode
commit c3d6569a43322f371e7ba0ad386112723757ac8f upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:36:00 +02:00
..
2024-04-03 15:19:30 +02:00
2024-05-25 16:21:31 +02:00
2024-02-05 20:12:58 +00:00
2022-09-24 07:00:00 +02:00
2023-09-13 09:43:05 +02:00
2022-09-11 20:26:07 -07:00
2024-02-23 09:12:45 +01:00
2023-09-23 11:11:10 +02:00
2022-09-24 07:00:00 +02:00
2024-03-26 18:20:28 -04:00
2023-08-30 16:11:10 +02:00
2022-10-10 14:21:11 -07:00
2023-01-04 11:29:01 +01:00