summaryrefslogtreecommitdiff
path: root/drivers/block
AgeCommit message (Collapse)AuthorFilesLines
10 daysdrbd: fix null-pointer dereference on local read errorChristoph Böhmwalder1-1/+2
commit 0d195d3b205ca90db30d70d09d7bb6909aac178f upstream. In drbd_request_endio(), READ_COMPLETED_WITH_ERROR is passed to __req_mod() with a NULL peer_device: __req_mod(req, what, NULL, &m); The READ_COMPLETED_WITH_ERROR handler then unconditionally passes this NULL peer_device to drbd_set_out_of_sync(), which dereferences it, causing a null-pointer dereference. Fix this by obtaining the peer_device via first_peer_device(device), matching how drbd_req_destroy() handles the same situation. Cc: stable@vger.kernel.org Reported-by: Tuo Li <islituo@gmail.com> Link: https://lore.kernel.org/linux-block/20260104165355.151864-1-islituo@gmail.com Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
10 daysdrbd: fix "LOGIC BUG" in drbd_al_begin_io_nonblock()Lars Ellenberg2-31/+27
commit ab140365fb62c0bdab22b2f516aff563b2559e3b upstream. Even though we check that we "should" be able to do lc_get_cumulative() while holding the device->al_lock spinlock, it may still fail, if some other code path decided to do lc_try_lock() with bad timing. If that happened, we logged "LOGIC BUG for enr=...", but still did not return an error. The rest of the code now assumed that this request has references for the relevant activity log extents. The implcations are that during an active resync, mutual exclusivity of resync versus application IO is not guaranteed. And a potential crash at this point may not realizs that these extents could have been target of in-flight IO and would need to be resynced just in case. Also, once the request completes, it will give up activity log references it does not even hold, which will trigger a BUG_ON(refcnt == 0) in lc_put(). Fix: Do not crash the kernel for a condition that is harmless during normal operation: also catch "e->refcnt == 0", not only "e == NULL" when being noisy about "al_complete_io() called on inactive extent %u\n". And do not try to be smart and "guess" whether something will work, then be surprised when it does not. Deal with the fact that it may or may not work. If it does not, remember a possible "partially in activity log" state (only possible for requests that cross extent boundaries), and return an error code from drbd_al_begin_io_nonblock(). A latter call for the same request will then resume from where we left off. Cc: stable@vger.kernel.org Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-03-04rnbd-srv: Zero the rsp buffer before using itMd Haris Iqbal1-0/+3
[ Upstream commit 69d26698e4fd44935510553809007151b2fe4db5 ] Before using the data buffer to send back the response message, zero it completely. This prevents any stray bytes to be picked up by the client side when there the message is exchanged between different protocol versions. Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com> Signed-off-by: Jack Wang <jinpu.wang@ionos.com> Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04ublk: Validate SQE128 flag before accessing the cmdGovindarajulu Varadarajan1-3/+3
[ Upstream commit da7e4b75e50c087d2031a92f6646eb90f7045a67 ] ublk_ctrl_cmd_dump() accesses (header *)sqe->cmd before IO_URING_F_SQE128 flag check. This could cause out of boundary memory access. Move the SQE128 flag check earlier in ublk_ctrl_uring_cmd() to return -EINVAL immediately if the flag is not set. Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Signed-off-by: Govindarajulu Varadarajan <govind.varadar@gmail.com> Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-11ublk: fix deadlock when reading partition tableMing Lei1-3/+27
commit c258f5c4502c9667bccf5d76fa731ab9c96687c1 upstream. When one process(such as udev) opens ublk block device (e.g., to read the partition table via bdev_open()), a deadlock[1] can occur: 1. bdev_open() grabs disk->open_mutex 2. The process issues read I/O to ublk backend to read partition table 3. In __ublk_complete_rq(), blk_update_request() or blk_mq_end_request() runs bio->bi_end_io() callbacks 4. If this triggers fput() on file descriptor of ublk block device, the work may be deferred to current task's task work (see fput() implementation) 5. This eventually calls blkdev_release() from the same context 6. blkdev_release() tries to grab disk->open_mutex again 7. Deadlock: same task waiting for a mutex it already holds The fix is to run blk_update_request() and blk_mq_end_request() with bottom halves disabled. This forces blkdev_release() to run in kernel work-queue context instead of current task work context, and allows ublk server to make forward progress, and avoids the deadlock. Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Link: https://github.com/ublk-org/ublksrv/issues/170 [1] Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> [axboe: rewrite comment in ublk] Signed-off-by: Jens Axboe <axboe@kernel.dk> [ The fix omits the change in __ublk_do_auto_buf_reg() since this function doesn't exist in Linux 6.6. ] Signed-off-by: Alva Lan <alvalan9@foxmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-11rbd: check for EOD after exclusive lock is ensured to be heldIlya Dryomov1-12/+21
commit bd3884a204c3b507e6baa9a4091aa927f9af5404 upstream. Similar to commit 870611e4877e ("rbd: get snapshot context after exclusive lock is ensured to be held"), move the "beyond EOD" check into the image request state machine so that it's performed after exclusive lock is ensured to be held. This avoids various race conditions which can arise when the image is shrunk under I/O (in practice, mostly readahead). In one such scenario rbd_assert(objno < rbd_dev->object_map_size); can be triggered if a close-to-EOD read gets queued right before the shrink is initiated and the EOD check is performed against an outdated mapping_size. After the resize is done on the server side and exclusive lock is (re)acquired bringing along the new (now shrunk) object map, the read starts going through the state machine and rbd_obj_may_exist() gets invoked on an object that is out of bounds of rbd_dev->object_map array. Cc: stable@vger.kernel.org Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Dongsheng Yang <dongsheng.yang@linux.dev> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-30null_blk: fix kmemleak by releasing references to fault configfs itemsNilay Shroff1-1/+11
commit 40b94ec7edbbb867c4e26a1a43d2b898f04b93c5 upstream. When CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION is enabled, the null-blk driver sets up fault injection support by creating the timeout_inject, requeue_inject, and init_hctx_fault_inject configfs items as children of the top-level nullbX configfs group. However, when the nullbX device is removed, the references taken to these fault-config configfs items are not released. As a result, kmemleak reports a memory leak, for example: unreferenced object 0xc00000021ff25c40 (size 32): comm "mkdir", pid 10665, jiffies 4322121578 hex dump (first 32 bytes): 69 6e 69 74 5f 68 63 74 78 5f 66 61 75 6c 74 5f init_hctx_fault_ 69 6e 6a 65 63 74 00 88 00 00 00 00 00 00 00 00 inject.......... backtrace (crc 1a018c86): __kmalloc_node_track_caller_noprof+0x494/0xbd8 kvasprintf+0x74/0xf4 config_item_set_name+0xf0/0x104 config_group_init_type_name+0x48/0xfc fault_config_init+0x48/0xf0 0xc0080000180559e4 configfs_mkdir+0x304/0x814 vfs_mkdir+0x49c/0x604 do_mkdirat+0x314/0x3d0 sys_mkdir+0xa0/0xd8 system_call_exception+0x1b0/0x4f0 system_call_vectored_common+0x15c/0x2ec Fix this by explicitly releasing the references to the fault-config configfs items when dropping the reference to the top-level nullbX configfs group. Cc: stable@vger.kernel.org Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Fixes: bb4c19e030f4 ("block: null_blk: make fault-injection dynamically configurable per device") Signed-off-by: Nilay Shroff <nilay@linux.ibm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11floppy: fix for PAGE_SIZE != 4KBRene Rebe1-1/+1
commit 82d20481024cbae2ea87fe8b86d12961bfda7169 upstream. For years I wondered why the floppy driver does not just work on sparc64, e.g: root@SUNW_375_0066:# disktype /dev/fd0 disktype: Can't open /dev/fd0: No such device or address [ 525.341906] disktype: attempt to access beyond end of device fd0: rw=0, sector=0, nr_sectors = 16 limit=8 [ 525.341991] floppy: error 10 while reading block 0 Turns out floppy.c __floppy_read_block_0 tries to read one page for the first test read to determine the disk size and thus fails if that is greater than 4k. Adjust minimum MAX_DISK_SIZE to PAGE_SIZE to fix floppy on sparc64 and likely all other PAGE_SIZE != 4KB configs. Cc: stable@vger.kernel.org Signed-off-by: René Rebe <rene@exactco.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11block: rnbd-clt: Fix signedness bug in init_dev()Dan Carpenter1-1/+1
[ Upstream commit 1ddb815fdfd45613c32e9bd1f7137428f298e541 ] The "dev->clt_device_id" variable is set using ida_alloc_max() which returns an int and in particular it returns negative error codes. Change the type from u32 to int to fix the error checking. Fixes: c9b5645fd8ca ("block: rnbd-clt: Fix leaked ID in init_dev()") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11block: rnbd-clt: Fix leaked ID in init_dev()Thomas Fourier1-5/+8
[ Upstream commit c9b5645fd8ca10f310e41b07540f98e6a9720f40 ] If kstrdup() fails in init_dev(), then the newly allocated ID is lost. Fixes: 64e8a6ece1a5 ("block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name") Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com> Acked-by: Jack Wang <jinpu.wang@ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11ublk: prevent invalid access with DEBUGKevin Brodsky1-2/+2
[ Upstream commit c6a45ee7607de3a350008630f4369b1b5ac80884 ] ublk_ch_uring_cmd_local() may jump to the out label before initialising the io pointer. This will cause trouble if DEBUG is defined, because the pr_devel() call dereferences io. Clang reports: drivers/block/ublk_drv.c:2403:6: error: variable 'io' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] 2403 | if (tag >= ub->dev_info.queue_depth) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/block/ublk_drv.c:2492:32: note: uninitialized use occurs here 2492 | __func__, cmd_op, tag, ret, io->flags); | Fix this by initialising io to NULL and checking it before dereferencing it. Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11ublk: complete command synchronously on errorCaleb Sander Mateos1-5/+6
[ Upstream commit 603f9be21c1894e462416e3324962d6c9c2b95f8 ] In case of an error, ublk's ->uring_cmd() functions currently return -EIOCBQUEUED and immediately call io_uring_cmd_done(). -EIOCBQUEUED and io_uring_cmd_done() are intended for asynchronous completions. For synchronous completions, the ->uring_cmd() function can just return the negative return code directly. This skips io_uring_cmd_del_cancelable(), and deferring the completion to task work. So return the error code directly from __ublk_ch_uring_cmd() and ublk_ctrl_uring_cmd(). Update ublk_ch_uring_cmd_cb(), which currently ignores the return value from __ublk_ch_uring_cmd(), to call io_uring_cmd_done() for synchronous completions. Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20250225212456.2902549-1-csander@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Stable-dep-of: c6a45ee7607d ("ublk: prevent invalid access with DEBUG") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11ublk: make sure io cmd handled in submitter task contextMing Lei1-1/+21
[ Upstream commit 3421c7f68bba52281bbb38bc76c18dc03cb689e4 ] In well-done ublk server implementation, ublk io command won't be linked into any link chain. Meantime they are always handled in no-wait style, so basically io cmd is always handled in submitter task context. However, the server may set IOSQE_ASYNC, or io command is linked to one chain mistakenly, then we may still run into io-wq context and ctx->uring_lock isn't held. So in case of IO_URING_F_UNLOCKED, schedule this command by io_uring_cmd_complete_in_task to force running it in submitter task. Then ublk_ch_uring_cmd_local() is guaranteed to run with context uring_lock held, and we needn't to worry about sync among submission code path any more. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20231009093324.957829-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Stable-dep-of: c6a45ee7607d ("ublk: prevent invalid access with DEBUG") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11ps3disk: use memcpy_{from,to}_bvec indexRene Rebe1-0/+4
[ Upstream commit 79bd8c9814a273fa7ba43399e1c07adec3fc95db ] With 6e0a48552b8c (ps3disk: use memcpy_{from,to}_bvec) converting ps3disk to new bvec helpers, incrementing the offset was accidently lost, corrupting consecutive buffers. Restore index for non-corrupted data transfers. Fixes: 6e0a48552b8c (ps3disk: use memcpy_{from,to}_bvec) Signed-off-by: René Rebe <rene@exactco.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11nbd: defer config unlock in nbd_genl_connectZheng Qixing1-1/+2
[ Upstream commit 1649714b930f9ea6233ce0810ba885999da3b5d4 ] There is one use-after-free warning when running NBD_CMD_CONNECT and NBD_CLEAR_SOCK: nbd_genl_connect nbd_alloc_and_init_config // config_refs=1 nbd_start_device // config_refs=2 set NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3 recv_work done // config_refs=2 NBD_CLEAR_SOCK // config_refs=1 close nbd // config_refs=0 refcount_inc -> uaf ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25 refcount_warn_saturate+0x12e/0x290 nbd_genl_connect+0x16d0/0x1ab0 genl_family_rcv_msg_doit+0x1f3/0x310 genl_rcv_msg+0x44a/0x790 The issue can be easily reproduced by adding a small delay before refcount_inc(&nbd->config_refs) in nbd_genl_connect(): mutex_unlock(&nbd->config_lock); if (!ret) { set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags); + printk("before sleep\n"); + mdelay(5 * 1000); + printk("after sleep\n"); refcount_inc(&nbd->config_refs); nbd_connect_reply(info, nbd->index); } Fixes: e46c7287b1c2 ("nbd: add a basic netlink interface") Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Reviewed-by: Yu Kuai <yukuai@fnnas.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11nbd: defer config put in recv_workZheng Qixing1-1/+1
[ Upstream commit 9517b82d8d422d426a988b213fdd45c6b417b86d ] There is one uaf issue in recv_work when running NBD_CLEAR_SOCK and NBD_CMD_RECONFIGURE: nbd_genl_connect // conf_ref=2 (connect and recv_work A) nbd_open // conf_ref=3 recv_work A done // conf_ref=2 NBD_CLEAR_SOCK // conf_ref=1 nbd_genl_reconfigure // conf_ref=2 (trigger recv_work B) close nbd // conf_ref=1 recv_work B config_put // conf_ref=0 atomic_dec(&config->recv_threads); -> UAF Or only running NBD_CLEAR_SOCK: nbd_genl_connect // conf_ref=2 nbd_open // conf_ref=3 NBD_CLEAR_SOCK // conf_ref=2 close nbd nbd_release config_put // conf_ref=1 recv_work config_put // conf_ref=0 atomic_dec(&config->recv_threads); -> UAF Commit 87aac3a80af5 ("nbd: call nbd_config_put() before notifying the waiter") moved nbd_config_put() to run before waking up the waiter in recv_work, in order to ensure that nbd_start_device_ioctl() would not be woken up while nbd->task_recv was still uncleared. However, in nbd_start_device_ioctl(), after being woken up it explicitly calls flush_workqueue() to make sure all current works are finished. Therefore, there is no need to move the config put ahead of the wakeup. Move nbd_config_put() to the end of recv_work, so that the reference is held for the whole lifetime of the worker thread. This makes sure the config cannot be freed while recv_work is still running, even if clear + reconfigure interleave. In addition, we don't need to worry about recv_work dropping the last nbd_put (which causes deadlock): path A (netlink with NBD_CFLAG_DESTROY_ON_DISCONNECT): connect // nbd_refs=1 (trigger recv_work) open nbd // nbd_refs=2 NBD_CLEAR_SOCK close nbd nbd_release nbd_disconnect_and_put flush_workqueue // recv_work done nbd_config_put nbd_put // nbd_refs=1 nbd_put // nbd_refs=0 queue_work path B (netlink without NBD_CFLAG_DESTROY_ON_DISCONNECT): connect // nbd_refs=2 (trigger recv_work) open nbd // nbd_refs=3 NBD_CLEAR_SOCK // conf_refs=2 close nbd nbd_release nbd_config_put // conf_refs=1 nbd_put // nbd_refs=2 recv_work done // conf_refs=0, nbd_refs=1 rmmod // nbd_refs=0 Reported-by: syzbot+56fbf4c7ddf65e95c7cc@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/6907edce.a70a0220.37351b.0014.GAE@google.com/T/ Fixes: 87aac3a80af5 ("nbd: make the config put is called before the notifying the waiter") Depends-on: e2daec488c57 ("nbd: Fix hungtask when nbd_config_put") Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15nbd: restrict sockets to TCP and UDPEric Dumazet1-0/+8
[ Upstream commit 9f7c02e031570e8291a63162c6c046dc15ff85b0 ] Recently, syzbot started to abuse NBD with all kinds of sockets. Commit cf1b2326b734 ("nbd: verify socket is supported during setup") made sure the socket supported a shutdown() method. Explicitely accept TCP and UNIX stream sockets. Fixes: cf1b2326b734 ("nbd: verify socket is supported during setup") Reported-by: syzbot+e1cd6bd8493060bd701d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/CANn89iJ+76eE3A_8S_zTpSyW5hvPRn6V57458hCZGY5hbH_bFA@mail.gmail.com/T/#m081036e8747cd7e2626c1da5d78c8b9d1e55b154 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mike Christie <mchristi@redhat.com> Cc: Richard W.M. Jones <rjones@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Yu Kuai <yukuai1@huaweicloud.com> Cc: linux-block@vger.kernel.org Cc: nbd@other.debian.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15null_blk: Fix the description of the cache_size module argumentGenjian Zhang1-1/+1
[ Upstream commit 7942b226e6b84df13b46b76c01d3b6e07a1b349e ] When executing modinfo null_blk, there is an error in the description of module parameter mbps, and the output information of cache_size is incomplete.The output of modinfo before and after applying this patch is as follows: Before: [...] parm: cache_size:ulong [...] parm: mbps:Cache size in MiB for memory-backed device. Default: 0 (none) (uint) [...] After: [...] parm: cache_size:Cache size in MiB for memory-backed device. Default: 0 (none) (ulong) [...] parm: mbps:Limit maximum bandwidth (in MiB/s). Default: 0 (no limit) (uint) [...] Fixes: 058efe000b31 ("null_blk: add module parameters for 4 options") Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-02loop: Avoid updating block size under exclusive ownerJan Kara1-9/+31
commit 7e49538288e523427beedd26993d446afef1a6fb upstream. Syzbot came up with a reproducer where a loop device block size is changed underneath a mounted filesystem. This causes a mismatch between the block device block size and the block size stored in the superblock causing confusion in various places such as fs/buffer.c. The particular issue triggered by syzbot was a warning in __getblk_slow() due to requested buffer size not matching block device block size. Fix the problem by getting exclusive hold of the loop device to change its block size. This fails if somebody (such as filesystem) has already an exclusive ownership of the block device and thus prevents modifying the loop device under some exclusive owner which doesn't expect it. Reported-by: syzbot+01ef7a8da81a975e1ccd@syzkaller.appspotmail.com Signed-off-by: Jan Kara <jack@suse.cz> Tested-by: syzbot+01ef7a8da81a975e1ccd@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20250711163202.19623-2-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-25Revert "loop: Avoid updating block size under exclusive owner"Eric Hagberg1-30/+8
Revert commit ce8da5d13d8c2a7b30b2fb376a22e8eb1a70b8bb which is commit 7e49538288e523427beedd26993d446afef1a6fb upstream. This reverts commit ce8da5d13d8c ("loop: Avoid updating block size under exclusive owner") for the 6.6 kernel, because if the LTP ioctl_loop06 test is run with this patch in place, the test will fail, it leaves the host unable to kexec into the kernel again (hangs forever) and "losetup -a" will hang on attempting to access the /dev/loopN device that the test has set up. The patch doesn't need to be reverted from 6.12, as it works fine there. Cc: stable@vger.kernel.org # 6.6.x Signed-off-by: Eric Hagberg <ehagberg@janestreet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-28drbd: add missing kref_get in handle_write_conflictsSarah Newman1-1/+5
[ Upstream commit 00c9c9628b49e368d140cfa61d7df9b8922ec2a8 ] With `two-primaries` enabled, DRBD tries to detect "concurrent" writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed. In handling "superseeded" writes, we forgot a kref_get, resulting in a premature drbd_destroy_device and use after free, and further to kernel crashes with symptoms. Relevance: No one should use DRBD as a random data generator, and apparently all users of "two-primaries" handle concurrent writes correctly on layer up. That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node. Which means that other than for "test cases", this code path is never taken in real life. FYI, in DRBD 9, things are handled differently nowadays. We still detect "write conflicts", but no longer try to be smart about them. We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault. Signed-off-by: Sarah Newman <srn@prgmr.com> Signed-off-by: Lars Ellenberg <lars@linbit.com> Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Link: https://lore.kernel.org/r/20250627095728.800688-1-christoph.boehmwalder@linbit.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28loop: Avoid updating block size under exclusive ownerJan Kara1-8/+30
[ Upstream commit 7e49538288e523427beedd26993d446afef1a6fb ] Syzbot came up with a reproducer where a loop device block size is changed underneath a mounted filesystem. This causes a mismatch between the block device block size and the block size stored in the superblock causing confusion in various places such as fs/buffer.c. The particular issue triggered by syzbot was a warning in __getblk_slow() due to requested buffer size not matching block device block size. Fix the problem by getting exclusive hold of the loop device to change its block size. This fails if somebody (such as filesystem) has already an exclusive ownership of the block device and thus prevents modifying the loop device under some exclusive owner which doesn't expect it. Reported-by: syzbot+01ef7a8da81a975e1ccd@syzkaller.appspotmail.com Signed-off-by: Jan Kara <jack@suse.cz> Tested-by: syzbot+01ef7a8da81a975e1ccd@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20250711163202.19623-2-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28sunvdc: Balance device refcount in vdc_port_mpgroup_checkMa Ke1-1/+3
commit 63ce53724637e2e7ba51fe3a4f78351715049905 upstream. Using device_find_child() to locate a probed virtual-device-port node causes a device refcount imbalance, as device_find_child() internally calls get_device() to increment the device’s reference count before returning its pointer. vdc_port_mpgroup_check() directly returns true upon finding a matching device without releasing the reference via put_device(). We should call put_device() to decrement refcount. As comment of device_find_child() says, 'NOTE: you will need to drop the reference with put_device() after use'. Found by code review. Cc: stable@vger.kernel.org Fixes: 3ee70591d6c4 ("sunvdc: prevent sunvdc panic when mpgroup disk added to guest domain") Signed-off-by: Ma Ke <make24@iscas.ac.cn> Link: https://lore.kernel.org/r/20250719075856.3447953-1-make24@iscas.ac.cn Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-15ublk: use vmalloc for ublk_device's __queuesCaleb Sander Mateos1-2/+2
[ Upstream commit c2f48453b7806d41f5a3270f206a5cd5640ed207 ] struct ublk_device's __queues points to an allocation with up to UBLK_MAX_NR_QUEUES (4096) queues, each of which have: - struct ublk_queue (48 bytes) - Tail array of up to UBLK_MAX_QUEUE_DEPTH (4096) struct ublk_io's, 32 bytes each This means the full allocation can exceed 512 MB, which may well be impossible to service with contiguous physical pages. Switch to kvcalloc() and kvfree(), since there is no need for physically contiguous memory. Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250620151008.3976463-2-csander@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17ublk: sanity check add_dev input for underflowRonnie Sahlberg1-1/+2
[ Upstream commit 969127bf0783a4ac0c8a27e633a9e8ea1738583f ] Add additional checks that queue depth and number of queues are non-zero. Signed-off-by: Ronnie Sahlberg <rsahlberg@whamcloud.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250626022046.235018-1-ronniesahlberg@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-17nbd: fix uaf in nbd_genl_connect() error pathZheng Qixing1-3/+3
[ Upstream commit aa9552438ebf015fc5f9f890dbfe39f0c53cf37e ] There is a use-after-free issue in nbd: block nbd6: Receive control failed (result -104) block nbd6: shutting down sockets ================================================================== BUG: KASAN: slab-use-after-free in recv_work+0x694/0xa80 drivers/block/nbd.c:1022 Write of size 4 at addr ffff8880295de478 by task kworker/u33:0/67 CPU: 2 UID: 0 PID: 67 Comm: kworker/u33:0 Not tainted 6.15.0-rc5-syzkaller-00123-g2c89c1b655c0 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: nbd6-recv recv_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] recv_work+0x694/0xa80 drivers/block/nbd.c:1022 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> nbd_genl_connect() does not properly stop the device on certain error paths after nbd_start_device() has been called. This causes the error path to put nbd->config while recv_work continue to use the config after putting it, leading to use-after-free in recv_work. This patch moves nbd_start_device() after the backend file creation. Reported-by: syzbot+48240bab47e705c53126@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68227a04.050a0220.f2294.00b5.GAE@google.com/T/ Fixes: 6497ef8df568 ("nbd: provide a way for userspace processes to identify device backends") Signed-off-by: Zheng Qixing <zhengqixing@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20250612132405.364904-1-zhengqixing@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10aoe: defer rexmit timer downdev work to workqueueJustin Sanders3-3/+11
[ Upstream commit cffc873d68ab09a0432b8212008c5613f8a70a2c ] When aoe's rexmit_timer() notices that an aoe target fails to respond to commands for more than aoe_deadsecs, it calls aoedev_downdev() which cleans the outstanding aoe and block queues. This can involve sleeping, such as in blk_mq_freeze_queue(), which should not occur in irq context. This patch defers that aoedev_downdev() call to the aoe device's workqueue. Link: https://bugzilla.kernel.org/show_bug.cgi?id=212665 Signed-off-by: Justin Sanders <jsanders.devel@gmail.com> Link: https://lore.kernel.org/r/20250610170600.869-2-jsanders.devel@gmail.com Tested-By: Valentin Kleibel <valentin@vrvis.at> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-27ublk: santizize the arguments from userspace when adding a deviceRonnie Sahlberg1-0/+3
[ Upstream commit 8c8472855884355caf3d8e0c50adf825f83454b2 ] Sanity check the values for queue depth and number of queues we get from userspace when adding a device. Signed-off-by: Ronnie Sahlberg <rsahlberg@whamcloud.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Fixes: 62fe99cef94a ("ublk: add read()/write() support for ublk char device") Link: https://lore.kernel.org/r/20250619021031.181340-1-ronniesahlberg@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-27aoe: clean device rq_list in aoedev_downdev()Justin Sanders1-0/+8
[ Upstream commit 7f90d45e57cb2ef1f0adcaf925ddffdfc5e680ca ] An aoe device's rq_list contains accepted block requests that are waiting to be transmitted to the aoe target. This queue was added as part of the conversion to blk_mq. However, the queue was not cleaned out when an aoe device is downed which caused blk_mq_freeze_queue() to sleep indefinitely waiting for those requests to complete, causing a hang. This fix cleans out the queue before calling blk_mq_freeze_queue(). Link: https://bugzilla.kernel.org/show_bug.cgi?id=212665 Fixes: 3582dd291788 ("aoe: convert aoeblk to blk-mq") Signed-off-by: Justin Sanders <jsanders.devel@gmail.com> Link: https://lore.kernel.org/r/20250610170600.869-1-jsanders.devel@gmail.com Tested-By: Valentin Kleibel <valentin@vrvis.at> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-02loop: aio inherit the ioprio of original requestYunlong Xing1-1/+1
[ Upstream commit 1fdb8188c3d505452b40cdb365b1bb32be533a8e ] Set cmd->iocb.ki_ioprio to the ioprio of loop device's request. The purpose is to inherit the original request ioprio in the aio flow. Signed-off-by: Yunlong Xing <yunlong.xing@unisoc.com> Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250414030159.501180-1-yunlong.xing@unisoc.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-04-25loop: LOOP_SET_FD: send uevents for partitionsThomas Weißschuh1-1/+2
commit 0dba7a05b9e47d8b546399117b0ddf2426dc6042 upstream. Remove the suppression of the uevents before scanning for partitions. The partitions inherit their suppression settings from their parent device, which lead to the uevents being dropped. This is similar to the same changes for LOOP_CONFIGURE done in commit bb430b694226 ("loop: LOOP_CONFIGURE: send uevents for partitions"). Fixes: 498ef5c777d9 ("loop: suppress uevents while reconfiguring the device") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20250415-loop-uevent-changed-v3-1-60ff69ac6088@linutronix.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-25loop: properly send KOBJ_CHANGED uevent for disk deviceThomas Weißschuh1-2/+2
commit e7bc0010ceb403d025100698586c8e760921d471 upstream. The original commit message and the wording "uncork" in the code comment indicate that it is expected that the suppressed event instances are automatically sent after unsuppressing. This is not the case, instead they are discarded. In effect this means that no "changed" events are emitted on the device itself by default. While each discovered partition does trigger a changed event on the device, devices without partitions don't have any event emitted. This makes udev miss the device creation and prompted workarounds in userspace. See the linked util-linux/losetup bug. Explicitly emit the events and drop the confusingly worded comments. Link: https://github.com/util-linux/util-linux/issues/2434 Fixes: 498ef5c777d9 ("loop: suppress uevents while reconfiguring the device") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://lore.kernel.org/r/20250415-loop-uevent-changed-v2-1-0c4e6a923b2a@linutronix.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-22zram: fix NULL pointer in comp_algorithm_show()Liu Shixin1-2/+2
commit f364cdeb38938f9d03061682b8ff3779dd1730e5 upstream. LTP reported a NULL pointer dereference as followed: CPU: 7 UID: 0 PID: 5995 Comm: cat Kdump: loaded Not tainted 6.12.0-rc6+ #3 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __pi_strcmp+0x24/0x140 lr : zcomp_available_show+0x60/0x100 [zram] sp : ffff800088b93b90 x29: ffff800088b93b90 x28: 0000000000000001 x27: 0000000000400cc0 x26: 0000000000000ffe x25: ffff80007b3e2388 x24: 0000000000000000 x23: ffff80007b3e2390 x22: ffff0004041a9000 x21: ffff80007b3e2900 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: ffff80007b3e2900 x9 : ffff80007b3cb280 x8 : 0101010101010101 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000040 x4 : 0000000000000000 x3 : 00656c722d6f7a6c x2 : 0000000000000000 x1 : ffff80007b3e2900 x0 : 0000000000000000 Call trace: __pi_strcmp+0x24/0x140 comp_algorithm_show+0x40/0x70 [zram] dev_attr_show+0x28/0x80 sysfs_kf_seq_show+0x90/0x140 kernfs_seq_show+0x34/0x48 seq_read_iter+0x1d4/0x4e8 kernfs_fop_read_iter+0x40/0x58 new_sync_read+0x9c/0x168 vfs_read+0x1a8/0x1f8 ksys_read+0x74/0x108 __arm64_sys_read+0x24/0x38 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x38/0x138 el0t_64_sync_handler+0xc0/0xc8 el0t_64_sync+0x188/0x190 The zram->comp_algs[ZRAM_PRIMARY_COMP] can be NULL in zram_add() if comp_algorithm_set() has not been called. User can access the zram device by sysfs after device_add_disk(), so there is a time window to trigger the NULL pointer dereference. Move it ahead device_add_disk() to make sure when user can access the zram device, it is ready. comp_algorithm_set() is protected by zram->init_lock in other places and no such problem. Link: https://lkml.kernel.org/r/20241108100147.3776123-1-liushixin2@huawei.com Fixes: 7ac07a26dea7 ("zram: preparation for multi-zcomp support") Signed-off-by: Liu Shixin <liushixin2@huawei.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [This fix does not backport zram_comp_params_reset which was introduced after v6.6, in commit f2bac7ad187d ("zram: introduce zcomp_params structure")] Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com> Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-13ublk: set_params: properly check if parameters can be appliedUday Shankar1-2/+5
[ Upstream commit 5ac60242b0173be83709603ebaf27a473f16c4e4 ] The parameters set by the set_params call are only applied to the block device in the start_dev call. So if a device has already been started, a subsequently issued set_params on that device will not have the desired effect, and should return an error. There is an existing check for this - set_params fails on devices in the LIVE state. But this check is not sufficient to cover the recovery case. In this case, the device will be in the QUIESCED or FAIL_IO states, so set_params will succeed. But this success is misleading, because the parameters will not be applied, since the device has already been started (by a previous ublk server). The bit UB_STATE_USED is set on completion of the start_dev; use it to detect and fail set_params commands which arrive too late to be applied (after start_dev). Signed-off-by: Uday Shankar <ushankar@purestorage.com> Fixes: 0aa73170eba5 ("ublk_drv: add SET_PARAMS/GET_PARAMS control command") Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250304-set_params-v1-1-17b5e0887606@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08nbd: don't allow reconnect after disconnectYu Kuai1-0/+1
[ Upstream commit 844b8cdc681612ff24df62cdefddeab5772fadf1 ] Following process can cause nbd_config UAF: 1) grab nbd_config temporarily; 2) nbd_genl_disconnect() flush all recv_work() and release the initial reference: nbd_genl_disconnect nbd_disconnect_and_put nbd_disconnect flush_workqueue(nbd->recv_workq) if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, ...)) nbd_config_put -> due to step 1), reference is still not zero 3) nbd_genl_reconfigure() queue recv_work() again; nbd_genl_reconfigure config = nbd_get_config_unlocked(nbd) if (!config) -> succeed if (!test_bit(NBD_RT_BOUND, ...)) -> succeed nbd_reconnect_socket queue_work(nbd->recv_workq, &args->work) 4) step 1) release the reference; 5) Finially, recv_work() will trigger UAF: recv_work nbd_config_put(nbd) -> nbd_config is freed atomic_dec(&config->recv_threads) -> UAF Fix the problem by clearing NBD_RT_BOUND in nbd_genl_disconnect(), so that nbd_genl_reconfigure() will fail. Fixes: b7aa3d39385d ("nbd: add a reconfigure netlink command") Reported-by: syzbot+6b0df248918b92c33e6a@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/675bfb65.050a0220.1a2d0d.0006.GAE@google.com/ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250103092859.3574648-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-23zram: fix potential UAF of zram tableKairui Song1-0/+1
commit 212fe1c0df4a150fb6298db2cfff267ceaba5402 upstream. If zram_meta_alloc failed early, it frees allocated zram->table without setting it NULL. Which will potentially cause zram_meta_free to access the table if user reset an failed and uninitialized device. Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@gmail.com Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device") Signed-off-by: Kairui Song <kasong@tencent.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-02virtio-blk: don't keep queue frozen during system suspendMing Lei1-2/+5
[ Upstream commit 7678abee0867e6b7fb89aa40f6e9f575f755fb37 ] Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's PM callbacks. And the motivation is to drain inflight IOs before suspending. block layer's queue freeze looks very handy, but it is also easy to cause deadlock, such as, any attempt to call into bio_queue_enter() may run into deadlock if the queue is frozen in current context. There are all kinds of ->suspend() called in suspend context, so keeping queue frozen in the whole suspend context isn't one good idea. And Marek reported lockdep warning[1] caused by virtio-blk's freeze queue in virtblk_freeze(). [1] https://lore.kernel.org/linux-block/ca16370e-d646-4eee-b9cc-87277c89c43c@samsung.com/ Given the motivation is to drain in-flight IOs, it can be done by calling freeze & unfreeze, meantime restore to previous behavior by keeping queue quiesced during suspend. Cc: Yi Sun <yi.sun@unisoc.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: virtualization@lists.linux.dev Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20241112125821.1475793-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-27zram: fix uninitialized ZRAM not releasing backing deviceKairui Song1-5/+4
commit 74363ec674cb172d8856de25776c8f3103f05e2f upstream. Setting backing device is done before ZRAM initialization. If we set the backing device, then remove the ZRAM module without initializing the device, the backing device reference will be leaked and the device will be hold forever. Fix this by always reset the ZRAM fully on rmmod or reset store. Link: https://lkml.kernel.org/r/20241209165717.94215-3-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song <kasong@tencent.com> Reported-by: Desheng Wu <deshengwu@tencent.com> Suggested-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-27zram: refuse to use zero sized block device as backing deviceKairui Song1-0/+6
commit be48c412f6ebf38849213c19547bc6d5b692b5e5 upstream. Patch series "zram: fix backing device setup issue", v2. This series fixes two bugs of backing device setting: - ZRAM should reject using a zero sized (or the uninitialized ZRAM device itself) as the backing device. - Fix backing device leaking when removing a uninitialized ZRAM device. This patch (of 2): Setting a zero sized block device as backing device is pointless, and one can easily create a recursive loop by setting the uninitialized ZRAM device itself as its own backing device by (zram0 is uninitialized): echo /dev/zram0 > /sys/block/zram0/backing_dev It's definitely a wrong config, and the module will pin itself, kernel should refuse doing so in the first place. By refusing to use zero sized device we avoided misuse cases including this one above. Link: https://lkml.kernel.org/r/20241209165717.94215-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20241209165717.94215-2-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song <kasong@tencent.com> Reported-by: Desheng Wu <deshengwu@tencent.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-14zram: clear IDLE flag in mark_idle()Sergey Senozhatsky1-0/+2
[ Upstream commit d37da422edb0664a2037e6d7d42fe6d339aae78a ] If entry does not fulfill current mark_idle() parameters, e.g. cutoff time, then we should clear its ZRAM_IDLE from previous mark_idle() invocations. Consider the following case: - mark_idle() cutoff time 8h - mark_idle() cutoff time 4h - writeback() idle - will writeback entries with cutoff time 8h, while it should only pick entries with cutoff time 4h The bug was reported by Shin Kawamura. Link: https://lkml.kernel.org/r/20241028153629.1479791-3-senozhatsky@chromium.org Fixes: 755804d16965 ("zram: introduce an aged idle interface") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Shin Kawamura <kawasin@google.com> Acked-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14zram: do not mark idle slots that cannot be idleSergey Senozhatsky1-7/+18
[ Upstream commit b967fa1ba72b5da2b6d9bf95f0b13420a59e0701 ] ZRAM_SAME slots cannot be post-processed (writeback or recompress) so do not mark them ZRAM_IDLE. Same with ZRAM_WB slots, they cannot be ZRAM_IDLE because they are not in zsmalloc pool anymore. Link: https://lkml.kernel.org/r/20240917021020.883356-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: d37da422edb0 ("zram: clear IDLE flag in mark_idle()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14zram: split memory-tracking and ac-time trackingSergey Senozhatsky3-16/+24
[ Upstream commit a7a0350583ba51d8cde6180bb51d704b89a3b29e ] ZRAM_MEMORY_TRACKING enables two features: - per-entry ac-time tracking - debugfs interface The latter one is the reason why memory-tracking depends on DEBUG_FS, while the former one is used far beyond debugging these days. Namely ac-time is used for fine grained writeback of idle entries (pages). Move ac-time tracking under its own config option so that it can be enabled (along with writeback) on systems without DEBUG_FS. [senozhatsky@chromium.org: ifdef fixup, per Dmytro] Link: https://lkml.kernel.org/r/20231117013543.540280-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20231115024223.4133148-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dmytro Maluka <dmaluka@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: d37da422edb0 ("zram: clear IDLE flag in mark_idle()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-09zram: clear IDLE flag after recompressionSergey Senozhatsky1-0/+7
commit f85219096648b251a81e9fe24a1974590cfc417d upstream. Patch series "zram: IDLE flag handling fixes", v2. zram can wrongly preserve ZRAM_IDLE flag on its entries which can result in premature post-processing (writeback and recompression) of such entries. This patch (of 2) Recompression should clear ZRAM_IDLE flag on the entries it has accessed, because otherwise some entries, specifically those for which recompression has failed, become immediate candidate entries for another post-processing (e.g. writeback). Consider the following case: - recompression marks entries IDLE every 4 hours and attempts to recompress them - some entries are incompressible, so we keep them intact and hence preserve IDLE flag - writeback marks entries IDLE every 8 hours and writebacks IDLE entries, however we have IDLE entries left from recompression, so writeback prematurely writebacks those entries. The bug was reported by Shin Kawamura. Link: https://lkml.kernel.org/r/20241028153629.1479791-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20241028153629.1479791-2-senozhatsky@chromium.org Fixes: 84b33bf78889 ("zram: introduce recompress sysfs knob") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Shin Kawamura <kawasin@google.com> Acked-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09ublk: fix error code for unsupported commandMing Lei1-1/+1
commit 34c1227035b3ab930a1ae6ab6f22fec1af8ab09e upstream. ENOTSUPP is for kernel use only, and shouldn't be sent to userspace. Fix it by replacing it with EOPNOTSUPP. Cc: stable@vger.kernel.org Fixes: bfbcef036396 ("ublk_drv: move ublk_get_device_from_id into ublk_ctrl_uring_cmd") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241119030646.2319030-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09ublk: fix ublk_ch_mmap() for 64K page sizeMing Lei1-3/+12
commit d369735e02ef122d19d4c3d093028da0eb400636 upstream. In ublk_ch_mmap(), queue id is calculated in the following way: (vma->vm_pgoff << PAGE_SHIFT) / `max_cmd_buf_size` 'max_cmd_buf_size' is equal to `UBLK_MAX_QUEUE_DEPTH * sizeof(struct ublksrv_io_desc)` and UBLK_MAX_QUEUE_DEPTH is 4096 and part of UAPI, so 'max_cmd_buf_size' is always page aligned in 4K page size kernel. However, it isn't true in 64K page size kernel. Fixes the issue by always rounding up 'max_cmd_buf_size' with PAGE_SIZE. Cc: stable@vger.kernel.org Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241111110718.1394001-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09virtio_blk: reverse request order in virtio_queue_rqsChristoph Hellwig1-25/+21
[ Upstream commit 7f212e997edbb7a2cb85cef2ac14265dfaf88717 ] blk_mq_flush_plug_list submits requests in the reverse order that they were submitted, which leads to a rather suboptimal I/O pattern especially in rotational devices. Fix this by rewriting virtio_queue_rqs so that it always pops the requests from the passed in request list, and then adds them to the head of a local submit list. This actually simplifies the code a bit as it removes the complicated list splicing, at the cost of extra updates of the rq_next pointer. As that should be cache hot anyway it should be an easy price to pay. Fixes: 0e9911fa768f ("virtio-blk: support mq_ops->queue_rqs()") Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241113152050.157179-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-09brd: defer automatic disk creation until module initialization succeedsYang Erkun1-22/+44
[ Upstream commit 826cc42adf44930a633d11a5993676d85ddb0842 ] My colleague Wupeng found the following problems during fault injection: BUG: unable to handle page fault for address: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Call Trace: <TASK> blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() is calling loop_add() after __register_blkdev() succeeds and is ignoring disk_add() failure from loop_add(), for loop_add() failure is not fatal and successfully created disks are already visible to bdev_open(). brd_init() is currently calling brd_alloc() before __register_blkdev() succeeds and is releasing successfully created disks when brd_init() returns an error. This can cause UAF for the latter two case: case 1: T1: modprobe brd brd_init brd_alloc(0) // success add_disk disk_scan_partitions bdev_file_open_by_dev // alloc file fput // won't free until back to userspace brd_alloc(1) // failed since mem alloc error inject // error path for modprobe will release code segment // back to userspace __fput blkdev_release bdev_release blkdev_put_whole bdev->bd_disk->fops->release // fops is freed now, UAF! case 2: T1: T2: modprobe brd brd_init brd_alloc(0) // success open(/dev/ram0) brd_alloc(1) // fail // error path for modprobe close(/dev/ram0) ... /* UAF! */ bdev->bd_disk->fops->release Fix this problem by following what loop_init() does. Besides, reintroduce brd_devices_mutex to help serialize modifications to brd_list. Fixes: 7f9b348cb5e9 ("brd: convert to blk_alloc_disk/blk_cleanup_disk") Reported-by: Wupeng Ma <mawupeng1@huawei.com> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241030034914.907829-1-yangerkun@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-22ublk: don't allow user copy for unprivileged deviceMing Lei1-1/+10
commit 42aafd8b48adac1c3b20fe5892b1b91b80c1a1e6 upstream. UBLK_F_USER_COPY requires userspace to call write() on ublk char device for filling request buffer, and unprivileged device can't be trusted. So don't allow user copy for unprivileged device. Cc: stable@vger.kernel.org Fixes: 1172d5b8beca ("ublk: support user copy") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241016134847.2911721-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-17zram: don't free statically defined namesAndrey Skvortsov1-2/+4
[ Upstream commit 486fd58af7ac1098b68370b1d4d9f94a2a1c7124 ] When CONFIG_ZRAM_MULTI_COMP isn't set ZRAM_SECONDARY_COMP can hold default_compressor, because it's the same offset as ZRAM_PRIMARY_COMP, so we need to make sure that we don't attempt to kfree() the statically defined compressor name. This is detected by KASAN. ================================================================== Call trace: kfree+0x60/0x3a0 zram_destroy_comps+0x98/0x198 [zram] zram_reset_device+0x22c/0x4a8 [zram] reset_store+0x1bc/0x2d8 [zram] dev_attr_store+0x44/0x80 sysfs_kf_write+0xfc/0x188 kernfs_fop_write_iter+0x28c/0x428 vfs_write+0x4dc/0x9b8 ksys_write+0x100/0x1f8 __arm64_sys_write+0x74/0xb8 invoke_syscall+0xd8/0x260 el0_svc_common.constprop.0+0xb4/0x240 do_el0_svc+0x48/0x68 el0_svc+0x40/0xc8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 ================================================================== Link: https://lkml.kernel.org/r/20240923164843.1117010-1-andrej.skvortzov@gmail.com Fixes: 684826f8271a ("zram: free secondary algorithms names") Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com> Closes: https://lore.kernel.org/lkml/57130e48-dbb6-4047-a8c7-ebf5aaea93f4@linux.vnet.ibm.com/ Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Jens Axboe <axboe@kernel.dk> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com> Cc: Chris Li <chrisl@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17zram: free secondary algorithms namesSergey Senozhatsky1-0/+5
[ Upstream commit 684826f8271ad97580b138b9ffd462005e470b99 ] We need to kfree() secondary algorithms names when reset zram device that had multi-streams, otherwise we leak memory. [senozhatsky@chromium.org: kfree(NULL) is legal] Link: https://lkml.kernel.org/r/20240917013021.868769-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20240911025600.3681789-1-senozhatsky@chromium.org Fixes: 001d92735701 ("zram: add recompression algorithm sysfs knob") Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
generated by cgit v1.2.3 (git 2.39.0) at 2026-04-04 22:57:37 +0300