| Message ID | 20240122223230.4000595-7-dhowells@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | netfs, afs, cifs, cachefiles, erofs: Miscellaneous fixes | expand |
On 1/23/24 6:32 AM, David Howells wrote: > 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 > --- > > Notes: > Changes > ======= > ver #2) > - Move check of object->ondemand into cachefiles_ondemand_init_object() > > fs/cachefiles/ondemand.c | 3 +++ > 1 file changed, 3 insertions(+) > > 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 Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
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
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 --- Notes: Changes ======= ver #2) - Move check of object->ondemand into cachefiles_ondemand_init_object() fs/cachefiles/ondemand.c | 3 +++ 1 file changed, 3 insertions(+)