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2025-07-24cachefiles: Fix the incorrect return value in __cachefiles_write()Zizhi Wo2-5/+1
[ Upstream commit 6b89819b06d8d339da414f06ef3242f79508be5e ] In __cachefiles_write(), if the return value of the write operation > 0, it is set to 0. This makes it impossible to distinguish scenarios where a partial write has occurred, and will affect the outer calling functions: 1) cachefiles_write_complete() will call "term_func" such as netfs_write_subrequest_terminated(). When "ret" in __cachefiles_write() is used as the "transferred_or_error" of this function, it can not distinguish the amount of data written, makes the WARN meaningless. 2) cachefiles_ondemand_fd_write_iter() can only assume all writes were successful by default when "ret" is 0, and unconditionally return the full length specified by user space. Fix it by modifying "ret" to reflect the actual number of bytes written. Furthermore, returning a value greater than 0 from __cachefiles_write() does not affect other call paths, such as cachefiles_issue_write() and fscache_write(). Fixes: 047487c947e8 ("cachefiles: Implement the I/O routines") Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Link: https://lore.kernel.org/20250703024418.2809353-1-wozizhi@huaweicloud.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-21cachefiles: Fix NULL pointer dereference in object->fileZizhi Wo2-10/+34
commit 31ad74b20227ce6b40910ff78b1c604e42975cf1 upstream. At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime are inconsistent, and the user-space invocation to anon_fd uses object->file. Following is the process that triggers the issue: [write fd] [umount] cachefiles_ondemand_fd_write_iter fscache_cookie_state_machine cachefiles_withdraw_cookie if (!file) return -ENOBUFS cachefiles_clean_up_object cachefiles_unmark_inode_in_use fput(object->file) object->file = NULL // file NULL pointer dereference! __cachefiles_write(..., file, ...) Fix this issue by add an additional reference count to the object->file before write/llseek, and decrement after it finished. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Link: https://lore.kernel.org/r/20241107110649.3980193-5-wozizhi@huawei.com Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Bin Lan <lanbincn@qq.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-23cachefiles: Parse the "secctx" immediatelyMax Kellermann3-11/+12
[ Upstream commit e5a8b6446c0d370716f193771ccacf3260a57534 ] Instead of storing an opaque string, call security_secctx_to_secid() right in the "secctx" command handler and store only the numeric "secid". This eliminates an unnecessary string allocation and allows the daemon to receive errors when writing the "secctx" command instead of postponing the error to the "bind" command handler. For example, if the kernel was built without `CONFIG_SECURITY`, "bind" will return `EOPNOTSUPP`, but the daemon doesn't know why. With this patch, the "secctx" will instead return `EOPNOTSUPP` which is the right context for this error. This patch adds a boolean flag `have_secid` because I'm not sure if we can safely assume that zero is the special secid value for "not set". This appears to be true for SELinux, Smack and AppArmor, but since this attribute is not documented, I'm unable to derive a stable guarantee for that. Signed-off-by: Max Kellermann <max.kellermann@ionos.com> Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20241209141554.638708-1-max.kellermann@ionos.com/ Link: https://lore.kernel.org/r/20241213135013.2964079-6-dhowells@redhat.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14cachefiles: Fix missing pos updates in cachefiles_ondemand_fd_write_iter()Zizhi Wo1-1/+3
[ Upstream commit 56f4856b425a30e1d8b3e41e6cde8bfba90ba5f8 ] In the erofs on-demand loading scenario, read and write operations are usually delivered through "off" and "len" contained in read req in user mode. Naturally, pwrite is used to specify a specific offset to complete write operations. However, if the write(not pwrite) syscall is called multiple times in the read-ahead scenario, we need to manually update ki_pos after each write operation to update file->f_pos. This step is currently missing from the cachefiles_ondemand_fd_write_iter function, added to address this issue. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Link: https://lore.kernel.org/r/20241107110649.3980193-3-wozizhi@huawei.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17cachefiles: fix dentry leak in cachefiles_open_file()Baokun Li1-4/+3
commit da6ef2dffe6056aad3435e6cf7c6471c2a62187c upstream. A dentry leak may be caused when a lookup cookie and a cull are concurrent: P1 | P2 ----------------------------------------------------------- cachefiles_lookup_cookie cachefiles_look_up_object lookup_one_positive_unlocked // get dentry cachefiles_cull inode->i_flags |= S_KERNEL_FILE; cachefiles_open_file cachefiles_mark_inode_in_use __cachefiles_mark_inode_in_use can_use = false if (!(inode->i_flags & S_KERNEL_FILE)) can_use = true return false return false // Returns an error but doesn't put dentry After that the following WARNING will be triggered when the backend folder is umounted: ================================================================== BUG: Dentry 000000008ad87947{i=7a,n=Dx_1_1.img} still in use (1) [unmount of ext4 sda] WARNING: CPU: 4 PID: 359261 at fs/dcache.c:1767 umount_check+0x5d/0x70 CPU: 4 PID: 359261 Comm: umount Not tainted 6.6.0-dirty #25 RIP: 0010:umount_check+0x5d/0x70 Call Trace: <TASK> d_walk+0xda/0x2b0 do_one_tree+0x20/0x40 shrink_dcache_for_umount+0x2c/0x90 generic_shutdown_super+0x20/0x160 kill_block_super+0x1a/0x40 ext4_kill_sb+0x22/0x40 deactivate_locked_super+0x35/0x80 cleanup_mnt+0x104/0x160 ================================================================== Whether cachefiles_open_file() returns true or false, the reference count obtained by lookup_positive_unlocked() in cachefiles_look_up_object() should be released. Therefore release that reference count in cachefiles_look_up_object() to fix the above issue and simplify the code. Fixes: 1f08c925e7a3 ("cachefiles: Implement backing file wrangling") Cc: stable@kernel.org Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240829083409.3788142-1-libaokun@huaweicloud.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-25cachefiles: fix slab-use-after-free in cachefiles_withdraw_cookie()Baokun Li2-2/+34
[ Upstream commit 5d8f805789072ea7fd39504694b7bd17e5f751c4 ] We got the following issue in our fault injection stress test: ================================================================== BUG: KASAN: slab-use-after-free in cachefiles_withdraw_cookie+0x4d9/0x600 Read of size 8 at addr ffff888118efc000 by task kworker/u78:0/109 CPU: 13 PID: 109 Comm: kworker/u78:0 Not tainted 6.8.0-dirty #566 Call Trace: <TASK> kasan_report+0x93/0xc0 cachefiles_withdraw_cookie+0x4d9/0x600 fscache_cookie_state_machine+0x5c8/0x1230 fscache_cookie_worker+0x91/0x1c0 process_one_work+0x7fa/0x1800 [...] Allocated by task 117: kmalloc_trace+0x1b3/0x3c0 cachefiles_acquire_volume+0xf3/0x9c0 fscache_create_volume_work+0x97/0x150 process_one_work+0x7fa/0x1800 [...] Freed by task 120301: kfree+0xf1/0x2c0 cachefiles_withdraw_cache+0x3fa/0x920 cachefiles_put_unbind_pincount+0x1f6/0x250 cachefiles_daemon_release+0x13b/0x290 __fput+0x204/0xa00 task_work_run+0x139/0x230 do_exit+0x87a/0x29b0 [...] ================================================================== Following is the process that triggers the issue: p1 | p2 ------------------------------------------------------------ fscache_begin_lookup fscache_begin_volume_access fscache_cache_is_live(fscache_cache) cachefiles_daemon_release cachefiles_put_unbind_pincount cachefiles_daemon_unbind cachefiles_withdraw_cache fscache_withdraw_cache fscache_set_cache_state(cache, FSCACHE_CACHE_IS_WITHDRAWN); cachefiles_withdraw_objects(cache) fscache_wait_for_objects(fscache) atomic_read(&fscache_cache->object_count) == 0 fscache_perform_lookup cachefiles_lookup_cookie cachefiles_alloc_object refcount_set(&object->ref, 1); object->volume = volume fscache_count_object(vcookie->cache); atomic_inc(&fscache_cache->object_count) cachefiles_withdraw_volumes cachefiles_withdraw_volume fscache_withdraw_volume __cachefiles_free_volume kfree(cachefiles_volume) fscache_cookie_state_machine cachefiles_withdraw_cookie cache = object->volume->cache; // cachefiles_volume UAF !!! After setting FSCACHE_CACHE_IS_WITHDRAWN, wait for all the cookie lookups to complete first, and then wait for fscache_cache->object_count == 0 to avoid the cookie exiting after the volume has been freed and triggering the above issue. Therefore call fscache_withdraw_volume() before calling cachefiles_withdraw_objects(). This way, after setting FSCACHE_CACHE_IS_WITHDRAWN, only the following two cases will occur: 1) fscache_begin_lookup fails in fscache_begin_volume_access(). 2) fscache_withdraw_volume() will ensure that fscache_count_object() has been executed before calling fscache_wait_for_objects(). Fixes: fe2140e2f57f ("cachefiles: Implement volume support") Suggested-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-4-libaokun@huaweicloud.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-25cachefiles: fix slab-use-after-free in fscache_withdraw_volume()Baokun Li1-0/+10
[ Upstream commit 522018a0de6b6fcce60c04f86dfc5f0e4b6a1b36 ] We got the following issue in our fault injection stress test: ================================================================== BUG: KASAN: slab-use-after-free in fscache_withdraw_volume+0x2e1/0x370 Read of size 4 at addr ffff88810680be08 by task ondemand-04-dae/5798 CPU: 0 PID: 5798 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #565 Call Trace: kasan_check_range+0xf6/0x1b0 fscache_withdraw_volume+0x2e1/0x370 cachefiles_withdraw_volume+0x31/0x50 cachefiles_withdraw_cache+0x3ad/0x900 cachefiles_put_unbind_pincount+0x1f6/0x250 cachefiles_daemon_release+0x13b/0x290 __fput+0x204/0xa00 task_work_run+0x139/0x230 Allocated by task 5820: __kmalloc+0x1df/0x4b0 fscache_alloc_volume+0x70/0x600 __fscache_acquire_volume+0x1c/0x610 erofs_fscache_register_volume+0x96/0x1a0 erofs_fscache_register_fs+0x49a/0x690 erofs_fc_fill_super+0x6c0/0xcc0 vfs_get_super+0xa9/0x140 vfs_get_tree+0x8e/0x300 do_new_mount+0x28c/0x580 [...] Freed by task 5820: kfree+0xf1/0x2c0 fscache_put_volume.part.0+0x5cb/0x9e0 erofs_fscache_unregister_fs+0x157/0x1b0 erofs_kill_sb+0xd9/0x1c0 deactivate_locked_super+0xa3/0x100 vfs_get_super+0x105/0x140 vfs_get_tree+0x8e/0x300 do_new_mount+0x28c/0x580 [...] ================================================================== Following is the process that triggers the issue: mount failed | daemon exit ------------------------------------------------------------ deactivate_locked_super cachefiles_daemon_release erofs_kill_sb erofs_fscache_unregister_fs fscache_relinquish_volume __fscache_relinquish_volume fscache_put_volume(fscache_volume, fscache_volume_put_relinquish) zero = __refcount_dec_and_test(&fscache_volume->ref, &ref); cachefiles_put_unbind_pincount cachefiles_daemon_unbind cachefiles_withdraw_cache cachefiles_withdraw_volumes list_del_init(&volume->cache_link) fscache_free_volume(fscache_volume) cache->ops->free_volume cachefiles_free_volume list_del_init(&cachefiles_volume->cache_link); kfree(fscache_volume) cachefiles_withdraw_volume fscache_withdraw_volume fscache_volume->n_accesses // fscache_volume UAF !!! The fscache_volume in cache->volumes must not have been freed yet, but its reference count may be 0. So use the new fscache_try_get_volume() helper function try to get its reference count. If the reference count of fscache_volume is 0, fscache_put_volume() is freeing it, so wait for it to be removed from cache->volumes. If its reference count is not 0, call cachefiles_withdraw_volume() with reference count protection to avoid the above issue. Fixes: fe2140e2f57f ("cachefiles: Implement volume support") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-3-libaokun@huaweicloud.com Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-25cachefiles: make on-demand read killableBaokun Li1-12/+28
[ Upstream commit bc9dde6155464e906e630a0a5c17a4cab241ffbb ] Replacing wait_for_completion() with wait_for_completion_killable() in cachefiles_ondemand_send_req() allows us to kill processes that might trigger a hunk_task if the daemon is abnormal. But now only CACHEFILES_OP_READ is killable, because OP_CLOSE and OP_OPEN is initiated from kworker context and the signal is prohibited in these kworker. Note that when the req in xas changes, i.e. xas_load(&xas) != req, it means that a process will complete the current request soon, so wait again for the request to be completed. In addition, add the cachefiles_ondemand_finish_req() helper function to simplify the code. Suggested-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-13-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-25cachefiles: Set object to close if ondemand_id < 0 in copenZizhi Wo1-1/+6
[ Upstream commit 4f8703fb3482f92edcfd31661857b16fec89c2c0 ] If copen is maliciously called in the user mode, it may delete the request corresponding to the random id. And the request may have not been read yet. Note that when the object is set to reopen, the open request will be done with the still reopen state in above case. As a result, the request corresponding to this object is always skipped in select_req function, so the read request is never completed and blocks other process. Fix this issue by simply set object to close if its id < 0 in copen. Signed-off-by: Zizhi Wo <wozizhi@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-11-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-25cachefiles: add consistency check for copen/creadBaokun Li1-7/+20
[ Upstream commit a26dc49df37e996876f50a0210039b2d211fdd6f ] This prevents malicious processes from completing random copen/cread requests and crashing the system. Added checks are listed below: * Generic, copen can only complete open requests, and cread can only complete read requests. * For copen, ondemand_id must not be 0, because this indicates that the request has not been read by the daemon. * For cread, the object corresponding to fd and req should be the same. Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-7-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: add missing lock protection when pollingJingbo Xu1-2/+2
[ Upstream commit cf5bb09e742a9cf6349127e868329a8f69b7a014 ] Add missing lock protection in poll routine when iterating xarray, otherwise: Even with RCU read lock held, only the slot of the radix tree is ensured to be pinned there, while the data structure (e.g. struct cachefiles_req) stored in the slot has no such guarantee. The poll routine will iterate the radix tree and dereference cachefiles_req accordingly. Thus RCU read lock is not adequate in this case and spinlock is needed here. Fixes: b817e22b2e91 ("cachefiles: narrow the scope of triggering EPOLLIN events in ondemand mode") Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-10-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: cyclic allocation of msg_id to avoid reuseBaokun Li2-4/+17
[ Upstream commit 19f4f399091478c95947f6bd7ad61622300c30d9 ] Reusing the msg_id after a maliciously completed reopen request may cause a read request to remain unprocessed and result in a hung, as shown below: t1 | t2 | t3 ------------------------------------------------- cachefiles_ondemand_select_req cachefiles_ondemand_object_is_close(A) cachefiles_ondemand_set_object_reopening(A) queue_work(fscache_object_wq, &info->work) ondemand_object_worker cachefiles_ondemand_init_object(A) cachefiles_ondemand_send_req(OPEN) // get msg_id 6 wait_for_completion(&req_A->done) cachefiles_ondemand_daemon_read // read msg_id 6 req_A cachefiles_ondemand_get_fd copy_to_user // Malicious completion msg_id 6 copen 6,-1 cachefiles_ondemand_copen complete(&req_A->done) // will not set the object to close // because ondemand_id && fd is valid. // ondemand_object_worker() is done // but the object is still reopening. // new open req_B cachefiles_ondemand_init_object(B) cachefiles_ondemand_send_req(OPEN) // reuse msg_id 6 process_open_req copen 6,A.size // The expected failed copen was executed successfully Expect copen to fail, and when it does, it closes fd, which sets the object to close, and then close triggers reopen again. However, due to msg_id reuse resulting in a successful copen, the anonymous fd is not closed until the daemon exits. Therefore read requests waiting for reopen to complete may trigger hung task. To avoid this issue, allocate the msg_id cyclically to avoid reusing the msg_id for a very short duration of time. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-9-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: wait for ondemand_object_worker to finish when dropping objectHou Tao1-0/+3
[ Upstream commit 12e009d60852f7bce0afc373ca0b320f14150418 ] When queuing ondemand_object_worker() to re-open the object, cachefiles_object is not pinned. The cachefiles_object may be freed when the pending read request is completed intentionally and the related erofs is umounted. If ondemand_object_worker() runs after the object is freed, it will incur use-after-free problem as shown below. process A processs B process C process D cachefiles_ondemand_send_req() // send a read req X // wait for its completion // close ondemand fd cachefiles_ondemand_fd_release() // set object as CLOSE cachefiles_ondemand_daemon_read() // set object as REOPENING queue_work(fscache_wq, &info->ondemand_work) // close /dev/cachefiles cachefiles_daemon_release cachefiles_flush_reqs complete(&req->done) // read req X is completed // umount the erofs fs cachefiles_put_object() // object will be freed cachefiles_ondemand_deinit_obj_info() kmem_cache_free(object) // both info and object are freed ondemand_object_worker() When dropping an object, it is no longer necessary to reopen the object, so use cancel_work_sync() to cancel or wait for ondemand_object_worker() to finish. Fixes: 0a7e54c1959c ("cachefiles: resend an open request if the read request's object is closed") Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-8-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: cancel all requests for the object that is being droppedBaokun Li1-0/+19
[ Upstream commit 751f524635a4f076117d714705eeddadaf6748ee ] Because after an object is dropped, requests for that object are useless, cancel them to avoid causing other problems. This prepares for the later addition of cancel_work_sync(). After the reopen requests is generated, cancel it to avoid cancel_work_sync() blocking by waiting for daemon to complete the reopen requests. Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-7-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 12e009d60852 ("cachefiles: wait for ondemand_object_worker to finish when dropping object") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: stop sending new request when dropping objectBaokun Li2-2/+10
[ Upstream commit b2415d1f4566b6939acacc69637eaa57815829c1 ] Added CACHEFILES_ONDEMAND_OBJSTATE_DROPPING indicates that the cachefiles object is being dropped, and is set after the close request for the dropped object completes, and no new requests are allowed to be sent after this state. This prepares for the later addition of cancel_work_sync(). It prevents leftover reopen requests from being sent, to avoid processing unnecessary requests and to avoid cancel_work_sync() blocking by waiting for daemon to complete the reopen requests. Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-6-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 12e009d60852 ("cachefiles: wait for ondemand_object_worker to finish when dropping object") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: narrow the scope of triggering EPOLLIN events in ondemand modeJia Zhu2-2/+24
[ Upstream commit b817e22b2e91257ace32a6768c3c003faeaa1c5c ] Don't trigger EPOLLIN when there are only reopening read requests in xarray. Suggested-by: Xin Yin <yinxin.x@bytedance.com> Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Link: https://lore.kernel.org/r/20231120041422.75170-5-zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 12e009d60852 ("cachefiles: wait for ondemand_object_worker to finish when dropping object") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-18cachefiles: propagate errors from vfs_getxattr() to avoid infinite loopBaokun Li1-1/+4
[ Upstream commit 0ece614a52bc9d219b839a6a29282b30d10e0c48 ] In cachefiles_check_volume_xattr(), the error returned by vfs_getxattr() is not passed to ret, so it ends up returning -ESTALE, which leads to an endless loop as follows: cachefiles_acquire_volume retry: ret = cachefiles_check_volume_xattr ret = -ESTALE xlen = vfs_getxattr // return -EIO // The ret is not updated when xlen < 0, so -ESTALE is returned. return ret // Supposed to jump out of the loop at this judgement. if (ret != -ESTALE) goto error_dir; cachefiles_bury_object // EIO causes rename failure goto retry; Hence propagate the error returned by vfs_getxattr() to avoid the above issue. Do the same in cachefiles_check_auxdata(). Fixes: 32e150037dce ("fscache, cachefiles: Store the volume coherency data") Fixes: 72b957856b0c ("cachefiles: Implement metadata/coherency data storage in xattrs") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240628062930.2467993-5-libaokun@huaweicloud.com Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles, erofs: Fix NULL deref in when cachefiles is not doing ondemand-modeDavid Howells1-0/+3
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>
2024-06-21cachefiles: flush all requests after setting CACHEFILES_DEADBaokun Li2-1/+4
[ Upstream commit 85e833cd7243bda7285492b0653c3abb1e2e757b ] In ondemand mode, when the daemon is processing an open request, if the kernel flags the cache as CACHEFILES_DEAD, the cachefiles_daemon_write() will always return -EIO, so the daemon can't pass the copen to the kernel. Then the kernel process that is waiting for the copen triggers a hung_task. Since the DEAD state is irreversible, it can only be exited by closing /dev/cachefiles. Therefore, after calling cachefiles_io_error() to mark the cache as CACHEFILES_DEAD, if in ondemand mode, flush all requests to avoid the above hungtask. We may still be able to read some of the cached data before closing the fd of /dev/cachefiles. Note that this relies on the patch that adds reference counting to the req, otherwise it may UAF. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-12-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: defer exposing anon_fd until after copy_to_user() succeedsBaokun Li1-20/+33
[ Upstream commit 4b4391e77a6bf24cba2ef1590e113d9b73b11039 ] After installing the anonymous fd, we can now see it in userland and close it. However, at this point we may not have gotten the reference count of the cache, but we will put it during colse fd, so this may cause a cache UAF. So grab the cache reference count before fd_install(). In addition, by kernel convention, fd is taken over by the user land after fd_install(), and the kernel should not call close_fd() after that, i.e., it should call fd_install() after everything is ready, thus fd_install() is called after copy_to_user() succeeds. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Suggested-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-10-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: never get a new anonymous fd if ondemand_id is validBaokun Li1-6/+28
[ Upstream commit 4988e35e95fc938bdde0e15880fe72042fc86acf ] Now every time the daemon reads an open request, it gets a new anonymous fd and ondemand_id. With the introduction of "restore", it is possible to read the same open request more than once, and therefore an object can have more than one anonymous fd. If the anonymous fd is not unique, the following concurrencies will result in an fd leak: t1 | t2 | t3 ------------------------------------------------------------ cachefiles_ondemand_init_object cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req cachefiles_ondemand_get_fd load->fd = fd0 ondemand_id = object_id0 ------ restore ------ cachefiles_ondemand_restore // restore REQ_A cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req cachefiles_ondemand_get_fd load->fd = fd1 ondemand_id = object_id1 process_open_req(REQ_A) write(devfd, ("copen %u,%llu", msg->msg_id, size)) cachefiles_ondemand_copen xa_erase(&cache->reqs, id) complete(&REQ_A->done) kfree(REQ_A) process_open_req(REQ_A) // copen fails due to no req // daemon close(fd1) cachefiles_ondemand_fd_release // set object closed -- umount -- cachefiles_withdraw_cookie cachefiles_ondemand_clean_object cachefiles_ondemand_init_close_req if (!cachefiles_ondemand_object_is_open(object)) return -ENOENT; // The fd0 is not closed until the daemon exits. However, the anonymous fd holds the reference count of the object and the object holds the reference count of the cookie. So even though the cookie has been relinquished, it will not be unhashed and freed until the daemon exits. In fscache_hash_cookie(), when the same cookie is found in the hash list, if the cookie is set with the FSCACHE_COOKIE_RELINQUISHED bit, then the new cookie waits for the old cookie to be unhashed, while the old cookie is waiting for the leaked fd to be closed, if the daemon does not exit in time it will trigger a hung task. To avoid this, allocate a new anonymous fd only if no anonymous fd has been allocated (ondemand_id == 0) or if the previously allocated anonymous fd has been closed (ondemand_id == -1). Moreover, returns an error if ondemand_id is valid, letting the daemon know that the current userland restore logic is abnormal and needs to be checked. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-9-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: remove err_put_fd label in cachefiles_ondemand_daemon_read()Baokun Li1-29/+16
[ Upstream commit 3e6d704f02aa4c50c7bc5fe91a4401df249a137b ] The err_put_fd label is only used once, so remove it to make the code more readable. In addition, the logic for deleting error request and CLOSE request is merged to simplify the code. Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-6-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: fix slab-use-after-free in cachefiles_ondemand_daemon_read()Baokun Li1-0/+3
[ Upstream commit da4a827416066191aafeeccee50a8836a826ba10 ] We got the following issue in a fuzz test of randomly issuing the restore command: ================================================================== BUG: KASAN: slab-use-after-free in cachefiles_ondemand_daemon_read+0xb41/0xb60 Read of size 8 at addr ffff888122e84088 by task ondemand-04-dae/963 CPU: 13 PID: 963 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #564 Call Trace: kasan_report+0x93/0xc0 cachefiles_ondemand_daemon_read+0xb41/0xb60 vfs_read+0x169/0xb50 ksys_read+0xf5/0x1e0 Allocated by task 116: kmem_cache_alloc+0x140/0x3a0 cachefiles_lookup_cookie+0x140/0xcd0 fscache_cookie_state_machine+0x43c/0x1230 [...] Freed by task 792: kmem_cache_free+0xfe/0x390 cachefiles_put_object+0x241/0x480 fscache_cookie_state_machine+0x5c8/0x1230 [...] ================================================================== Following is the process that triggers the issue: mount | daemon_thread1 | daemon_thread2 ------------------------------------------------------------ cachefiles_withdraw_cookie cachefiles_ondemand_clean_object(object) cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req msg->object_id = req->object->ondemand->ondemand_id ------ restore ------ cachefiles_ondemand_restore xas_for_each(&xas, req, ULONG_MAX) xas_set_mark(&xas, CACHEFILES_REQ_NEW) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req copy_to_user(_buffer, msg, n) xa_erase(&cache->reqs, id) complete(&REQ_A->done) ------ close(fd) ------ cachefiles_ondemand_fd_release cachefiles_put_object cachefiles_put_object kmem_cache_free(cachefiles_object_jar, object) REQ_A->object->ondemand->ondemand_id // object UAF !!! When we see the request within xa_lock, req->object must not have been freed yet, so grab the reference count of object before xa_unlock to avoid the above issue. Fixes: 0a7e54c1959c ("cachefiles: resend an open request if the read request's object is closed") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-5-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: fix slab-use-after-free in cachefiles_ondemand_get_fd()Baokun Li2-4/+20
[ Upstream commit de3e26f9e5b76fc628077578c001c4a51bf54d06 ] We got the following issue in a fuzz test of randomly issuing the restore command: ================================================================== BUG: KASAN: slab-use-after-free in cachefiles_ondemand_daemon_read+0x609/0xab0 Write of size 4 at addr ffff888109164a80 by task ondemand-04-dae/4962 CPU: 11 PID: 4962 Comm: ondemand-04-dae Not tainted 6.8.0-rc7-dirty #542 Call Trace: kasan_report+0x94/0xc0 cachefiles_ondemand_daemon_read+0x609/0xab0 vfs_read+0x169/0xb50 ksys_read+0xf5/0x1e0 Allocated by task 626: __kmalloc+0x1df/0x4b0 cachefiles_ondemand_send_req+0x24d/0x690 cachefiles_create_tmpfile+0x249/0xb30 cachefiles_create_file+0x6f/0x140 cachefiles_look_up_object+0x29c/0xa60 cachefiles_lookup_cookie+0x37d/0xca0 fscache_cookie_state_machine+0x43c/0x1230 [...] Freed by task 626: kfree+0xf1/0x2c0 cachefiles_ondemand_send_req+0x568/0x690 cachefiles_create_tmpfile+0x249/0xb30 cachefiles_create_file+0x6f/0x140 cachefiles_look_up_object+0x29c/0xa60 cachefiles_lookup_cookie+0x37d/0xca0 fscache_cookie_state_machine+0x43c/0x1230 [...] ================================================================== Following is the process that triggers the issue: mount | daemon_thread1 | daemon_thread2 ------------------------------------------------------------ cachefiles_ondemand_init_object cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req cachefiles_ondemand_get_fd copy_to_user(_buffer, msg, n) process_open_req(REQ_A) ------ restore ------ cachefiles_ondemand_restore xas_for_each(&xas, req, ULONG_MAX) xas_set_mark(&xas, CACHEFILES_REQ_NEW); cachefiles_daemon_read cachefiles_ondemand_daemon_read REQ_A = cachefiles_ondemand_select_req write(devfd, ("copen %u,%llu", msg->msg_id, size)); cachefiles_ondemand_copen xa_erase(&cache->reqs, id) complete(&REQ_A->done) kfree(REQ_A) cachefiles_ondemand_get_fd(REQ_A) fd = get_unused_fd_flags file = anon_inode_getfile fd_install(fd, file) load = (void *)REQ_A->msg.data; load->fd = fd; // load UAF !!! This issue is caused by issuing a restore command when the daemon is still alive, which results in a request being processed multiple times thus triggering a UAF. So to avoid this problem, add an additional reference count to cachefiles_req, which is held while waiting and reading, and then released when the waiting and reading is over. Note that since there is only one reference count for waiting, we need to avoid the same request being completed multiple times, so we can only complete the request if it is successfully removed from the xarray. Fixes: e73fa11a356c ("cachefiles: add restore command to recover inflight ondemand read requests") Suggested-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-4-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: add restore command to recover inflight ondemand read requestsJia Zhu3-0/+27
[ Upstream commit e73fa11a356ca0905c3cc648eaacc6f0f2d2c8b3 ] Previously, in ondemand read scenario, if the anonymous fd was closed by user daemon, inflight and subsequent read requests would return EIO. As long as the device connection is not released, user daemon can hold and restore inflight requests by setting the request flag to CACHEFILES_REQ_NEW. Suggested-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: Xin Yin <yinxin.x@bytedance.com> Link: https://lore.kernel.org/r/20231120041422.75170-6-zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 4b4391e77a6b ("cachefiles: defer exposing anon_fd until after copy_to_user() succeeds") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: add spin_lock for cachefiles_ondemand_infoBaokun Li2-1/+35
[ Upstream commit 0a790040838c736495d5afd6b2d636f159f817f1 ] The following concurrency may cause a read request to fail to be completed and result in a hung: t1 | t2 --------------------------------------------------------- cachefiles_ondemand_copen req = xa_erase(&cache->reqs, id) // Anon fd is maliciously closed. cachefiles_ondemand_fd_release xa_lock(&cache->reqs) cachefiles_ondemand_set_object_close(object) xa_unlock(&cache->reqs) cachefiles_ondemand_set_object_open // No one will ever close it again. cachefiles_ondemand_daemon_read cachefiles_ondemand_select_req // Get a read req but its fd is already closed. // The daemon can't issue a cread ioctl with an closed fd, then hung. So add spin_lock for cachefiles_ondemand_info to protect ondemand_id and state, thus we can avoid the above problem in cachefiles_ondemand_copen() by using ondemand_id to determine if fd has been closed. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-8-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: resend an open request if the read request's object is closedJia Zhu2-29/+72
[ Upstream commit 0a7e54c1959c0feb2de23397ec09c7692364313e ] When an anonymous fd is closed by user daemon, if there is a new read request for this file comes up, the anonymous fd should be re-opened to handle that read request rather than fail it directly. 1. Introduce reopening state for objects that are closed but have inflight/subsequent read requests. 2. No longer flush READ requests but only CLOSE requests when anonymous fd is closed. 3. Enqueue the reopen work to workqueue, thus user daemon could get rid of daemon_read context and handle that request smoothly. Otherwise, the user daemon will send a reopen request and wait for itself to process the request. Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Link: https://lore.kernel.org/r/20231120041422.75170-4-zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 0a790040838c ("cachefiles: add spin_lock for cachefiles_ondemand_info") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: extract ondemand info field from cachefiles_objectJia Zhu3-11/+56
[ Upstream commit 3c5ecfe16e7699011c12c2d44e55437415331fa3 ] We'll introduce a @work_struct field for @object in subsequent patches, it will enlarge the size of @object. As the result of that, this commit extracts ondemand info field from @object. Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Link: https://lore.kernel.org/r/20231120041422.75170-3-zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 0a790040838c ("cachefiles: add spin_lock for cachefiles_ondemand_info") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: introduce object ondemand stateJia Zhu2-12/+30
[ Upstream commit 357a18d033143617e9c7d420c8f0dd4cbab5f34d ] Previously, @ondemand_id field was used not only to identify ondemand state of the object, but also to represent the index of the xarray. This commit introduces @state field to decouple the role of @ondemand_id and adds helpers to access it. Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Link: https://lore.kernel.org/r/20231120041422.75170-2-zhujia.zj@bytedance.com Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Stable-dep-of: 0a790040838c ("cachefiles: add spin_lock for cachefiles_ondemand_info") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21cachefiles: remove requests from xarray during flushing requestsBaokun Li1-0/+1
[ Upstream commit 0fc75c5940fa634d84e64c93bfc388e1274ed013 ] Even with CACHEFILES_DEAD set, we can still read the requests, so in the following concurrency the request may be used after it has been freed: mount | daemon_thread1 | daemon_thread2 ------------------------------------------------------------ cachefiles_ondemand_init_object cachefiles_ondemand_send_req REQ_A = kzalloc(sizeof(*req) + data_len) wait_for_completion(&REQ_A->done) cachefiles_daemon_read cachefiles_ondemand_daemon_read // close dev fd cachefiles_flush_reqs complete(&REQ_A->done) kfree(REQ_A) xa_lock(&cache->reqs); cachefiles_ondemand_select_req req->msg.opcode != CACHEFILES_OP_READ // req use-after-free !!! xa_unlock(&cache->reqs); xa_destroy(&cache->reqs) Hence remove requests from cache->reqs when flushing them to avoid accessing freed requests. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240522114308.2402121-3-libaokun@huaweicloud.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01cachefiles: fix memory leak in cachefiles_add_cache()Baokun Li2-0/+3
commit e21a2f17566cbd64926fb8f16323972f7a064444 upstream. The following memory leak was reported after unbinding /dev/cachefiles: ================================================================== unreferenced object 0xffff9b674176e3c0 (size 192): comm "cachefilesd2", pid 680, jiffies 4294881224 hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc ea38a44b): [<ffffffff8eb8a1a5>] kmem_cache_alloc+0x2d5/0x370 [<ffffffff8e917f86>] prepare_creds+0x26/0x2e0 [<ffffffffc002eeef>] cachefiles_determine_cache_security+0x1f/0x120 [<ffffffffc00243ec>] cachefiles_add_cache+0x13c/0x3a0 [<ffffffffc0025216>] cachefiles_daemon_write+0x146/0x1c0 [<ffffffff8ebc4a3b>] vfs_write+0xcb/0x520 [<ffffffff8ebc5069>] ksys_write+0x69/0xf0 [<ffffffff8f6d4662>] do_syscall_64+0x72/0x140 [<ffffffff8f8000aa>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 ================================================================== Put the reference count of cache_cred in cachefiles_daemon_unbind() to fix the problem. And also put cache_cred in cachefiles_add_cache() error branch to avoid memory leaks. Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem") CC: stable@vger.kernel.org Signed-off-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20240217081431.796809-1-libaokun1@huawei.com Acked-by: David Howells <dhowells@redhat.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10mm, netfs, fscache: stop read optimisation when folio removed from pagecacheDavid Howells1-0/+2
[ Upstream commit b4fa966f03b7401ceacd4ffd7227197afb2b8376 ] Fscache has an optimisation by which reads from the cache are skipped until we know that (a) there's data there to be read and (b) that data isn't entirely covered by pages resident in the netfs pagecache. This is done with two flags manipulated by fscache_note_page_release(): if (... test_bit(FSCACHE_COOKIE_HAVE_DATA, &cookie->flags) && test_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags)) clear_bit(FSCACHE_COOKIE_NO_DATA_TO_READ, &cookie->flags); where the NO_DATA_TO_READ flag causes cachefiles_prepare_read() to indicate that netfslib should download from the server or clear the page instead. The fscache_note_page_release() function is intended to be called from ->releasepage() - but that only gets called if PG_private or PG_private_2 is set - and currently the former is at the discretion of the network filesystem and the latter is only set whilst a page is being written to the cache, so sometimes we miss clearing the optimisation. Fix this by following Willy's suggestion[1] and adding an address_space flag, AS_RELEASE_ALWAYS, that causes filemap_release_folio() to always call ->release_folio() if it's set, even if PG_private or PG_private_2 aren't set. Note that this would require folio_test_private() and page_has_private() to become more complicated. To avoid that, in the places[*] where these are used to conditionalise calls to filemap_release_folio() and try_to_release_page(), the tests are removed the those functions just jumped to unconditionally and the test is performed there. [*] There are some exceptions in vmscan.c where the check guards more than just a call to the releaser. I've added a function, folio_needs_release() to wrap all the checks for that. AS_RELEASE_ALWAYS should be set if a non-NULL cookie is obtained from fscache and cleared in ->evict_inode() before truncate_inode_pages_final() is called. Additionally, the FSCACHE_COOKIE_NO_DATA_TO_READ flag needs to be cleared and the optimisation cancelled if a cachefiles object already contains data when we open it. [dwysocha@redhat.com: call folio_mapping() inside folio_needs_release()] Link: https://github.com/DaveWysochanskiRH/kernel/commit/902c990e311120179fa5de99d68364b2947b79ec Link: https://lkml.kernel.org/r/20230628104852.3391651-3-dhowells@redhat.com Fixes: 1f67e6d0b188 ("fscache: Provide a function to note the release of a page") Fixes: 047487c947e8 ("cachefiles: Implement the I/O routines") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Reported-by: Rohith Surabattula <rohiths.msft@gmail.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Tested-by: SeongJae Park <sj@kernel.org> Cc: Daire Byrne <daire.byrne@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Steve French <sfrench@samba.org> Cc: Shyam Prasad N <nspmangalore@gmail.com> Cc: Rohith Surabattula <rohiths.msft@gmail.com> Cc: Dave Wysochanski <dwysocha@redhat.com> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jingbo Xu <jefflexu@linux.alibaba.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Xiubo Li <xiubli@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: 1898efcdbed3 ("block: update the stable_writes flag in bdev_add") Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-24cachefiles: use vfs_tmpfile_open() helperMiklos Szeredi1-20/+12
Use the vfs_tmpfile_open() helper instead of doing tmpfile creation and opening separately. The only minor difference is that previously no permission checking was done, while vfs_tmpfile_open() will call may_open() with zero access mask (i.e. no access is checked). Even if this would make a difference with callers caps (don't see how it could, even in the LSM codepaths) cachfiles raises caps before performing the tmpfile creation, so this extra permission check will not result in any regression. Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-09-24cachefiles: only pass inode to *mark_inode_inuse() helpersMiklos Szeredi1-33/+26
The only reason to pass dentry was because of a pr_notice() text. Move that to the two callers where it makes sense and add a WARN_ON() to the third. file_inode(file) is never NULL on an opened file. Remove check in cachefiles_unmark_inode_in_use(). Do not open code cachefiles_do_unmark_inode_in_use() in cachefiles_put_directory(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-09-24cachefiles: tmpfile error handling cleanupMiklos Szeredi1-29/+26
Separate the error labels from the success path and use 'ret' to store the error value before jumping to the error label. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-08-31cachefiles: make on-demand request distribution fairerXin Yin2-3/+10
For now, enqueuing and dequeuing on-demand requests all start from idx 0, this makes request distribution unfair. In the weighty concurrent I/O scenario, the request stored in higher idx will starve. Searching requests cyclically in cachefiles_ondemand_daemon_read, makes distribution fairer. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Reported-by: Yongqing Li <liyongqing@bytedance.com> Signed-off-by: Xin Yin <yinxin.x@bytedance.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20220817065200.11543-1-yinxin.x@bytedance.com/ # v1 Link: https://lore.kernel.org/r/20220825020945.2293-1-yinxin.x@bytedance.com/ # v2
2022-08-31cachefiles: fix error return code in cachefiles_ondemand_copen()Sun Ke1-3/+7
The cache_size field of copen is specified by the user daemon. If cache_size < 0, then the OPEN request is expected to fail, while copen itself shall succeed. However, returning 0 is indeed unexpected when cache_size is an invalid error code. Fix this by returning error when cache_size is an invalid error code. Changes ======= v4: update the code suggested by Dan v3: update the commit log suggested by Jingbo. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Sun Ke <sunke32@huawei.com> Suggested-by: Jeffle Xu <jefflexu@linux.alibaba.com> Suggested-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/20220818111935.1683062-1-sunke32@huawei.com/ # v2 Link: https://lore.kernel.org/r/20220818125038.2247720-1-sunke32@huawei.com/ # v3 Link: https://lore.kernel.org/r/20220826023515.3437469-1-sunke32@huawei.com/ # v4
2022-07-05cachefiles: narrow the scope of flushed requests when releasing fdJia Zhu1-1/+2
When an anonymous fd is released, only flush the requests associated with it, rather than all of requests in xarray. Fixes: 9032b6e8589f ("cachefiles: implement on-demand read") Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://listman.redhat.com/archives/linux-cachefs/2022-June/006937.html
2022-05-17cachefiles: add tracepoints for on-demand read modeJeffle Xu1-0/+7
Add tracepoints for on-demand read mode. Currently following tracepoints are added: OPEN request / COPEN reply CLOSE request READ request / CREAD reply write through anonymous fd release of anonymous fd Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-8-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: enable on-demand read modeJeffle Xu1-5/+12
Enable on-demand read mode by adding an optional parameter to the "bind" command. On-demand mode will be turned on when this parameter is "ondemand", i.e. "bind ondemand". Otherwise cachefiles will work in the original mode. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Link: https://lore.kernel.org/r/20220509074028.74954-7-jefflexu@linux.alibaba.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: implement on-demand readJeffle Xu3-2/+99
Implement the data plane of on-demand read mode. The early implementation [1] place the entry to cachefiles_ondemand_read() in fscache_read(). However, fscache_read() can only detect if the requested file range is fully cache miss, whilst we need to notify the user daemon as long as there's a hole inside the requested file range. Thus the entry is now placed in cachefiles_prepare_read(). When working in on-demand read mode, once a hole detected, the read routine will send a READ request to the user daemon. The user daemon needs to fetch the data and write it to the cache file. After sending the READ request, the read routine will hang there, until the READ request is handled by the user daemon. Then it will retry to read from the same file range. If no progress encountered, the read routine will fail then. A new NETFS_SREQ_ONDEMAND flag is introduced to indicate that on-demand read should be done when a cache miss encountered. [1] https://lore.kernel.org/all/20220406075612.60298-6-jefflexu@linux.alibaba.com/ #v8 Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-6-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: notify the user daemon when withdrawing cookieJeffle Xu3-0/+45
Notify the user daemon that cookie is going to be withdrawn, providing a hint that the associated anonymous fd can be closed. Be noted that this is only a hint. The user daemon may close the associated anonymous fd when receiving the CLOSE request, then it will receive another anonymous fd when the cookie gets looked up. Or it may ignore the CLOSE request, and keep writing data through the anonymous fd. However the next time the cookie gets looked up, the user daemon will still receive another new anonymous fd. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-5-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: unbind cachefiles gracefully in on-demand modeJeffle Xu3-3/+22
Add a refcount to avoid the deadlock in on-demand read mode. The on-demand read mode will pin the corresponding cachefiles object for each anonymous fd. The cachefiles object is unpinned when the anonymous fd gets closed. When the user daemon exits and the fd of "/dev/cachefiles" device node gets closed, it will wait for all cahcefiles objects getting withdrawn. Then if there's any anonymous fd getting closed after the fd of the device node, the user daemon will hang forever, waiting for all objects getting withdrawn. To fix this, add a refcount indicating if there's any object pinned by anonymous fds. The cachefiles cache gets unbound and withdrawn when the refcount is decreased to 0. It won't change the behaviour of the original mode, in which case the cachefiles cache gets unbound and withdrawn as long as the fd of the device node gets closed. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Link: https://lore.kernel.org/r/20220509074028.74954-4-jefflexu@linux.alibaba.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: notify the user daemon when looking up cookieJeffle Xu6-15/+524
Fscache/CacheFiles used to serve as a local cache for a remote networking fs. A new on-demand read mode will be introduced for CacheFiles, which can boost the scenario where on-demand read semantics are needed, e.g. container image distribution. The essential difference between these two modes is seen when a cache miss occurs: In the original mode, the netfs will fetch the data from the remote server and then write it to the cache file; in on-demand read mode, fetching the data and writing it into the cache is delegated to a user daemon. As the first step, notify the user daemon when looking up cookie. In this case, an anonymous fd is sent to the user daemon, through which the user daemon can write the fetched data to the cache file. Since the user daemon may move the anonymous fd around, e.g. through dup(), an object ID uniquely identifying the cache file is also attached. Also add one advisory flag (FSCACHE_ADV_WANT_CACHE_SIZE) suggesting that the cache file size shall be retrieved at runtime. This helps the scenario where one cache file contains multiple netfs files, e.g. for the purpose of deduplication. In this case, netfs itself has no idea the size of the cache file, whilst the user daemon should give the hint on it. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Link: https://lore.kernel.org/r/20220509074028.74954-3-jefflexu@linux.alibaba.com Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-05-17cachefiles: extract write routineJeffle Xu2-26/+45
Extract the generic routine of writing data to cache files, and make it generally available. This will be used by the following patch implementing on-demand read mode. Since it's called inside CacheFiles module, make the interface generic and unrelated to netfs_cache_resources. It is worth noting that, ki->inval_counter is not initialized after this cleanup. It shall not make any visible difference, since inval_counter is no longer used in the write completion routine, i.e. cachefiles_write_complete(). Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-2-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-04-09cachefiles: Fix KASAN slab-out-of-bounds in cachefiles_set_volume_xattrDave Wysochanski1-1/+1
Use the actual length of volume coherency data when setting the xattr to avoid the following KASAN report. BUG: KASAN: slab-out-of-bounds in cachefiles_set_volume_xattr+0xa0/0x350 [cachefiles] Write of size 4 at addr ffff888101e02af4 by task kworker/6:0/1347 CPU: 6 PID: 1347 Comm: kworker/6:0 Kdump: loaded Not tainted 5.18.0-rc1-nfs-fscache-netfs+ #13 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 Workqueue: events fscache_create_volume_work [fscache] Call Trace: <TASK> dump_stack_lvl+0x45/0x5a print_report.cold+0x5e/0x5db ? __lock_text_start+0x8/0x8 ? cachefiles_set_volume_xattr+0xa0/0x350 [cachefiles] kasan_report+0xab/0x120 ? cachefiles_set_volume_xattr+0xa0/0x350 [cachefiles] kasan_check_range+0xf5/0x1d0 memcpy+0x39/0x60 cachefiles_set_volume_xattr+0xa0/0x350 [cachefiles] cachefiles_acquire_volume+0x2be/0x500 [cachefiles] ? __cachefiles_free_volume+0x90/0x90 [cachefiles] fscache_create_volume_work+0x68/0x160 [fscache] process_one_work+0x3b7/0x6a0 worker_thread+0x2c4/0x650 ? process_one_work+0x6a0/0x6a0 kthread+0x16c/0x1a0 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Allocated by task 1347: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0x81/0xa0 cachefiles_set_volume_xattr+0x76/0x350 [cachefiles] cachefiles_acquire_volume+0x2be/0x500 [cachefiles] fscache_create_volume_work+0x68/0x160 [fscache] process_one_work+0x3b7/0x6a0 worker_thread+0x2c4/0x650 kthread+0x16c/0x1a0 ret_from_fork+0x22/0x30 The buggy address belongs to the object at ffff888101e02af0 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 4 bytes inside of 8-byte region [ffff888101e02af0, ffff888101e02af8) The buggy address belongs to the physical page: page:00000000a2292d70 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x101e02 flags: 0x17ffffc0000200(slab|node=0|zone=2|lastcpupid=0x1fffff) raw: 0017ffffc0000200 0000000000000000 dead000000000001 ffff888100042280 raw: 0000000000000000 0000000080660066 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888101e02980: fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc ffff888101e02a00: 00 fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc 00 >ffff888101e02a80: fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc 04 fc ^ ffff888101e02b00: fc fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc ffff888101e02b80: fc fc 00 fc fc fc fc 00 fc fc fc fc 00 fc fc fc ================================================================== Fixes: 413a4a6b0b55 "cachefiles: Fix volume coherency attribute" Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/20220405134649.6579-1-dwysocha@redhat.com/ # v1 Link: https://lore.kernel.org/r/20220405142810.8208-1-dwysocha@redhat.com/ # Incorrect v2
2022-04-09cachefiles: unmark inode in use in error pathJeffle Xu1-9/+24
Unmark inode in use if error encountered. If the in-use flag leakage occurs in cachefiles_open_file(), Cachefiles will complain "Inode already in use" when later another cookie with the same index key is looked up. If the in-use flag leakage occurs in cachefiles_create_tmpfile(), though the "Inode already in use" warning won't be triggered, fix the leakage anyway. Reported-by: Gao Xiang <hsiangkao@linux.alibaba.com> Fixes: 1f08c925e7a3 ("cachefiles: Implement backing file wrangling") Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-March/006615.html # v1 Link: https://listman.redhat.com/archives/linux-cachefs/2022-March/006618.html # v2
2022-04-01Merge tag 'netfs-prep-20220318' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull netfs updates from David Howells: "Netfs prep for write helpers. Having had a go at implementing write helpers and content encryption support in netfslib, it seems that the netfs_read_{,sub}request structs and the equivalent write request structs were almost the same and so should be merged, thereby requiring only one set of alloc/get/put functions and a common set of tracepoints. Merging the structs also has the advantage that if a bounce buffer is added to the request struct, a read operation can be performed to fill the bounce buffer, the contents of the buffer can be modified and then a write operation can be performed on it to send the data wherever it needs to go using the same request structure all the way through. The I/O handlers would then transparently perform any required crypto. This should make it easier to perform RMW cycles if needed. The potentially common functions and structs, however, by their names all proclaim themselves to be associated with the read side of things. The bulk of these changes alter this in the following ways: - Rename struct netfs_read_{,sub}request to netfs_io_{,sub}request. - Rename some enums, members and flags to make them more appropriate. - Adjust some comments to match. - Drop "read"/"rreq" from the names of common functions. For instance, netfs_get_read_request() becomes netfs_get_request(). - The ->init_rreq() and ->issue_op() methods become ->init_request() and ->issue_read(). I've kept the latter as a read-specific function and in another branch added an ->issue_write() method. The driver source is then reorganised into a number of files: fs/netfs/buffered_read.c Create read reqs to the pagecache fs/netfs/io.c Dispatchers for read and write reqs fs/netfs/main.c Some general miscellaneous bits fs/netfs/objects.c Alloc, get and put functions fs/netfs/stats.c Optional procfs statistics. and future development can be fitted into this scheme, e.g.: fs/netfs/buffered_write.c Modify the pagecache fs/netfs/buffered_flush.c Writeback from the pagecache fs/netfs/direct_read.c DIO read support fs/netfs/direct_write.c DIO write support fs/netfs/unbuffered_write.c Write modifications directly back Beyond the above changes, there are also some changes that affect how things work: - Make fscache_end_operation() generally available. - In the netfs tracing header, generate enums from the symbol -> string mapping tables rather than manually coding them. - Add a struct for filesystems that uses netfslib to put into their inode wrapper structs to hold extra state that netfslib is interested in, such as the fscache cookie. This allows netfslib functions to be set in filesystem operation tables and jumped to directly without having to have a filesystem wrapper. - Add a member to the struct added above to track the remote inode length as that may differ if local modifications are buffered. We may need to supply an appropriate EOF pointer when storing data (in AFS for example). - Pass extra information to netfs_alloc_request() so that the ->init_request() hook can access it and retain information to indicate the origin of the operation. - Make the ->init_request() hook return an error, thereby allowing a filesystem that isn't allowed to cache an inode (ceph or cifs, for example) to skip readahead. - Switch to using refcount_t for subrequests and add tracepoints to log refcount changes for the request and subrequest structs. - Add a function to consolidate dispatching a read request. Similar code is used in three places and another couple are likely to be added in the future" Link: https://lore.kernel.org/all/2639515.1648483225@warthog.procyon.org.uk/ * tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Maintain netfs_i_context::remote_i_size netfs: Keep track of the actual remote file size netfs: Split some core bits out into their own file netfs: Split fs/netfs/read_helper.c netfs: Rename read_helper.c to io.c netfs: Prepare to split read_helper.c netfs: Add a function to consolidate beginning a read netfs: Add a netfs inode context ceph: Make ceph_init_request() check caps on readahead netfs: Change ->init_request() to return an error code netfs: Refactor arguments for netfs_alloc_read_request netfs: Adjust the netfs_failure tracepoint to indicate non-subreq lines netfs: Trace refcounting on the netfs_io_subrequest struct netfs: Trace refcounting on the netfs_io_request struct netfs: Adjust the netfs_rreq tracepoint slightly netfs: Split netfs_io_* object handling out netfs: Finish off rename of netfs_read_request to netfs_io_request netfs: Rename netfs_read_*request to netfs_io_*request netfs: Generate enums from trace symbol mapping lists fscache: export fscache_end_operation()
2022-03-26Merge tag 'for-5.18/write-streams-2022-03-18' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+0
Pull NVMe write streams removal from Jens Axboe: "This removes the write streams support in NVMe. No vendor ever really shipped working support for this, and they are not interested in supporting it. With the NVMe support gone, we have nothing in the tree that supports this. Remove passing around of the hints. The only discussion point in this patchset imho is the fact that the file specific write hint setting/getting fcntl helpers will now return -1/EINVAL like they did before we supported write hints. No known applications use these functions, I only know of one prototype that I help do for RocksDB, and that's not used. That said, with a change like this, it's always a bit controversial. Alternatively, we could just make them return 0 and pretend it worked. It's placement based hints after all" * tag 'for-5.18/write-streams-2022-03-18' of git://git.kernel.dk/linux-block: fs: remove fs.f_write_hint fs: remove kiocb.ki_hint block: remove the per-bio/request write hint nvme: remove support or stream based temperature hint
2022-03-18netfs: Finish off rename of netfs_read_request to netfs_io_requestDavid Howells1-2/+2
Adjust helper function names and comments after mass rename of struct netfs_read_*request to struct netfs_io_*request. Changes ======= ver #2) - Make the changes in the docs also. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622992433.3564931.6684311087845150271.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678196111.1200972.5001114956865989528.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692892567.2099075.13895804222087028813.stgit@warthog.procyon.org.uk/ # v3
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