diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 6465e2574230..06cdf1a8a16f 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -133,7 +133,7 @@ static int cachefiles_daemon_open(struct inode *inode, struct file *file) return 0; } -static void cachefiles_flush_reqs(struct cachefiles_cache *cache) +void cachefiles_flush_reqs(struct cachefiles_cache *cache) { struct xarray *xa = &cache->reqs; struct cachefiles_req *req; @@ -159,6 +159,7 @@ static void cachefiles_flush_reqs(struct cachefiles_cache *cache) xa_for_each(xa, index, req) { req->error = -EIO; complete(&req->done); + __xa_erase(xa, index); } xa_unlock(xa); diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index d33169f0018b..6845a90cdfcc 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -55,6 +55,7 @@ struct cachefiles_ondemand_info { int ondemand_id; enum cachefiles_object_state state; struct cachefiles_object *object; + spinlock_t lock; }; /* @@ -138,6 +139,7 @@ static inline bool cachefiles_in_ondemand_mode(struct cachefiles_cache *cache) struct cachefiles_req { struct cachefiles_object *object; struct completion done; + refcount_t ref; int error; struct cachefiles_msg msg; }; @@ -186,6 +188,7 @@ extern int cachefiles_has_space(struct cachefiles_cache *cache, * daemon.c */ extern const struct file_operations cachefiles_daemon_fops; +extern void cachefiles_flush_reqs(struct cachefiles_cache *cache); extern void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache); extern void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache); @@ -424,6 +427,8 @@ do { \ pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__); \ fscache_io_error((___cache)->cache); \ set_bit(CACHEFILES_DEAD, &(___cache)->flags); \ + if (cachefiles_in_ondemand_mode(___cache)) \ + cachefiles_flush_reqs(___cache); \ } while (0) #define cachefiles_io_error_obj(object, FMT, ...) \ diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index 4ba42f1fa3b4..bce005f2b456 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -1,22 +1,42 @@ // SPDX-License-Identifier: GPL-2.0-or-later -#include #include #include #include "internal.h" +struct ondemand_anon_file { + struct file *file; + int fd; +}; + +static inline void cachefiles_req_put(struct cachefiles_req *req) +{ + if (refcount_dec_and_test(&req->ref)) + kfree(req); +} + static int cachefiles_ondemand_fd_release(struct inode *inode, struct file *file) { struct cachefiles_object *object = file->private_data; - struct cachefiles_cache *cache = object->volume->cache; - struct cachefiles_ondemand_info *info = object->ondemand; - int object_id = info->ondemand_id; + struct cachefiles_cache *cache; + struct cachefiles_ondemand_info *info; + int object_id; struct cachefiles_req *req; - XA_STATE(xas, &cache->reqs, 0); + XA_STATE(xas, NULL, 0); + + if (!object) + return 0; + + info = object->ondemand; + cache = object->volume->cache; + xas.xa = &cache->reqs; xa_lock(&cache->reqs); + spin_lock(&info->lock); + object_id = info->ondemand_id; info->ondemand_id = CACHEFILES_ONDEMAND_ID_CLOSED; cachefiles_ondemand_set_object_close(object); + spin_unlock(&info->lock); /* Only flush CACHEFILES_REQ_NEW marked req to avoid race with daemon_read */ xas_for_each_marked(&xas, req, ULONG_MAX, CACHEFILES_REQ_NEW) { @@ -76,12 +96,12 @@ static loff_t cachefiles_ondemand_fd_llseek(struct file *filp, loff_t pos, } static long cachefiles_ondemand_fd_ioctl(struct file *filp, unsigned int ioctl, - unsigned long arg) + unsigned long id) { struct cachefiles_object *object = filp->private_data; struct cachefiles_cache *cache = object->volume->cache; struct cachefiles_req *req; - unsigned long id; + XA_STATE(xas, &cache->reqs, id); if (ioctl != CACHEFILES_IOC_READ_COMPLETE) return -EINVAL; @@ -89,10 +109,15 @@ static long cachefiles_ondemand_fd_ioctl(struct file *filp, unsigned int ioctl, if (!test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags)) return -EOPNOTSUPP; - id = arg; - req = xa_erase(&cache->reqs, id); - if (!req) + xa_lock(&cache->reqs); + req = xas_load(&xas); + if (!req || req->msg.opcode != CACHEFILES_OP_READ || + req->object != object) { + xa_unlock(&cache->reqs); return -EINVAL; + } + xas_store(&xas, NULL); + xa_unlock(&cache->reqs); trace_cachefiles_ondemand_cread(object, id); complete(&req->done); @@ -116,10 +141,12 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args) { struct cachefiles_req *req; struct fscache_cookie *cookie; + struct cachefiles_ondemand_info *info; char *pid, *psize; unsigned long id; long size; int ret; + XA_STATE(xas, &cache->reqs, 0); if (!test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags)) return -EOPNOTSUPP; @@ -143,10 +170,18 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args) if (ret) return ret; - req = xa_erase(&cache->reqs, id); - if (!req) + xa_lock(&cache->reqs); + xas.xa_index = id; + req = xas_load(&xas); + if (!req || req->msg.opcode != CACHEFILES_OP_OPEN || + !req->object->ondemand->ondemand_id) { + xa_unlock(&cache->reqs); return -EINVAL; + } + xas_store(&xas, NULL); + xa_unlock(&cache->reqs); + info = req->object->ondemand; /* fail OPEN request if copen format is invalid */ ret = kstrtol(psize, 0, &size); if (ret) { @@ -166,6 +201,32 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args) goto out; } + spin_lock(&info->lock); + /* + * The anonymous fd was closed before copen ? Fail the request. + * + * 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. + */ + if (info->ondemand_id == CACHEFILES_ONDEMAND_ID_CLOSED) { + spin_unlock(&info->lock); + req->error = -EBADFD; + goto out; + } cookie = req->object->cookie; cookie->object_size = size; if (size) @@ -175,9 +236,15 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args) trace_cachefiles_ondemand_copen(req->object, id, size); cachefiles_ondemand_set_object_open(req->object); + spin_unlock(&info->lock); wake_up_all(&cache->daemon_pollwq); out: + spin_lock(&info->lock); + /* Need to set object close to avoid reopen status continuing */ + if (info->ondemand_id == CACHEFILES_ONDEMAND_ID_CLOSED) + cachefiles_ondemand_set_object_close(req->object); + spin_unlock(&info->lock); complete(&req->done); return ret; } @@ -205,14 +272,14 @@ int cachefiles_ondemand_restore(struct cachefiles_cache *cache, char *args) return 0; } -static int cachefiles_ondemand_get_fd(struct cachefiles_req *req) +static int cachefiles_ondemand_get_fd(struct cachefiles_req *req, + struct ondemand_anon_file *anon_file) { struct cachefiles_object *object; struct cachefiles_cache *cache; struct cachefiles_open *load; - struct file *file; u32 object_id; - int ret, fd; + int ret; object = cachefiles_grab_object(req->object, cachefiles_obj_get_ondemand_fd); @@ -224,35 +291,53 @@ static int cachefiles_ondemand_get_fd(struct cachefiles_req *req) if (ret < 0) goto err; - fd = get_unused_fd_flags(O_WRONLY); - if (fd < 0) { - ret = fd; + anon_file->fd = get_unused_fd_flags(O_WRONLY); + if (anon_file->fd < 0) { + ret = anon_file->fd; goto err_free_id; } - file = anon_inode_getfile("[cachefiles]", &cachefiles_ondemand_fd_fops, - object, O_WRONLY); - if (IS_ERR(file)) { - ret = PTR_ERR(file); + anon_file->file = anon_inode_getfile("[cachefiles]", + &cachefiles_ondemand_fd_fops, object, O_WRONLY); + if (IS_ERR(anon_file->file)) { + ret = PTR_ERR(anon_file->file); goto err_put_fd; } - file->f_mode |= FMODE_PWRITE | FMODE_LSEEK; - fd_install(fd, file); + spin_lock(&object->ondemand->lock); + if (object->ondemand->ondemand_id > 0) { + spin_unlock(&object->ondemand->lock); + /* Pair with check in cachefiles_ondemand_fd_release(). */ + anon_file->file->private_data = NULL; + ret = -EEXIST; + goto err_put_file; + } + + anon_file->file->f_mode |= FMODE_PWRITE | FMODE_LSEEK; load = (void *)req->msg.data; - load->fd = fd; + load->fd = anon_file->fd; object->ondemand->ondemand_id = object_id; + spin_unlock(&object->ondemand->lock); cachefiles_get_unbind_pincount(cache); trace_cachefiles_ondemand_open(object, &req->msg, load); return 0; +err_put_file: + fput(anon_file->file); + anon_file->file = NULL; err_put_fd: - put_unused_fd(fd); + put_unused_fd(anon_file->fd); + anon_file->fd = ret; err_free_id: xa_erase(&cache->ondemand_ids, object_id); err: + spin_lock(&object->ondemand->lock); + /* Avoid marking an opened object as closed. */ + if (object->ondemand->ondemand_id <= 0) + cachefiles_ondemand_set_object_close(object); + spin_unlock(&object->ondemand->lock); cachefiles_put_object(object, cachefiles_obj_put_ondemand_fd); return ret; } @@ -294,14 +379,28 @@ static struct cachefiles_req *cachefiles_ondemand_select_req(struct xa_state *xa return NULL; } +static inline bool cachefiles_ondemand_finish_req(struct cachefiles_req *req, + struct xa_state *xas, int err) +{ + if (unlikely(!xas || !req)) + return false; + + if (xa_cmpxchg(xas->xa, xas->xa_index, req, NULL, 0) != req) + return false; + + req->error = err; + complete(&req->done); + return true; +} + ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, char __user *_buffer, size_t buflen) { struct cachefiles_req *req; struct cachefiles_msg *msg; - unsigned long id = 0; size_t n; int ret = 0; + struct ondemand_anon_file anon_file; XA_STATE(xas, &cache->reqs, cache->req_id_next); xa_lock(&cache->reqs); @@ -330,42 +429,37 @@ ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, xas_clear_mark(&xas, CACHEFILES_REQ_NEW); cache->req_id_next = xas.xa_index + 1; + refcount_inc(&req->ref); + cachefiles_grab_object(req->object, cachefiles_obj_get_read_req); xa_unlock(&cache->reqs); - id = xas.xa_index; - if (msg->opcode == CACHEFILES_OP_OPEN) { - ret = cachefiles_ondemand_get_fd(req); - if (ret) { - cachefiles_ondemand_set_object_close(req->object); - goto error; - } + ret = cachefiles_ondemand_get_fd(req, &anon_file); + if (ret) + goto out; } - msg->msg_id = id; + msg->msg_id = xas.xa_index; msg->object_id = req->object->ondemand->ondemand_id; - if (copy_to_user(_buffer, msg, n) != 0) { + if (copy_to_user(_buffer, msg, n) != 0) ret = -EFAULT; - goto err_put_fd; + + if (msg->opcode == CACHEFILES_OP_OPEN) { + if (ret < 0) { + fput(anon_file.file); + put_unused_fd(anon_file.fd); + goto out; + } + fd_install(anon_file.fd, anon_file.file); } - - /* CLOSE request has no reply */ - if (msg->opcode == CACHEFILES_OP_CLOSE) { - xa_erase(&cache->reqs, id); - complete(&req->done); - } - - return n; - -err_put_fd: - if (msg->opcode == CACHEFILES_OP_OPEN) - close_fd(((struct cachefiles_open *)msg->data)->fd); -error: - xa_erase(&cache->reqs, id); - req->error = ret; - complete(&req->done); - return ret; +out: + cachefiles_put_object(req->object, cachefiles_obj_put_read_req); + /* Remove error request and CLOSE request has no reply */ + if (ret || msg->opcode == CACHEFILES_OP_CLOSE) + cachefiles_ondemand_finish_req(req, &xas, ret); + cachefiles_req_put(req); + return ret ? ret : n; } typedef int (*init_req_fn)(struct cachefiles_req *req, void *private); @@ -395,6 +489,7 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object, goto out; } + refcount_set(&req->ref, 1); req->object = object; init_completion(&req->done); req->msg.opcode = opcode; @@ -454,9 +549,19 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object, goto out; wake_up_all(&cache->daemon_pollwq); - wait_for_completion(&req->done); - ret = req->error; - kfree(req); +wait: + ret = wait_for_completion_killable(&req->done); + if (!ret) { + ret = req->error; + } else { + ret = -EINTR; + if (!cachefiles_ondemand_finish_req(req, &xas, ret)) { + /* Someone will complete it soon. */ + cpu_relax(); + goto wait; + } + } + cachefiles_req_put(req); return ret; out: /* Reset the object to close state in error handling path. @@ -578,6 +683,7 @@ int cachefiles_ondemand_init_obj_info(struct cachefiles_object *object, return -ENOMEM; object->ondemand->object = object; + spin_lock_init(&object->ondemand->lock); INIT_WORK(&object->ondemand->ondemand_work, ondemand_object_worker); return 0; } diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index dc51df0b118d..8fd928899a59 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -107,8 +107,16 @@ static int debugfs_parse_param(struct fs_context *fc, struct fs_parameter *param int opt; opt = fs_parse(fc, debugfs_param_specs, param, &result); - if (opt < 0) + if (opt < 0) { + /* + * We might like to report bad mount options here; but + * traditionally debugfs has ignored all mount options + */ + if (opt == -ENOPARAM) + return 0; + return opt; + } switch (opt) { case Opt_uid: diff --git a/fs/file.c b/fs/file.c index 8076aef9c210..a3b72aa64f11 100644 --- a/fs/file.c +++ b/fs/file.c @@ -486,12 +486,12 @@ struct files_struct init_files = { static unsigned int find_next_fd(struct fdtable *fdt, unsigned int start) { - unsigned int maxfd = fdt->max_fds; + unsigned int maxfd = fdt->max_fds; /* always multiple of BITS_PER_LONG */ unsigned int maxbit = maxfd / BITS_PER_LONG; unsigned int bitbit = start / BITS_PER_LONG; bitbit = find_next_zero_bit(fdt->full_fds_bits, maxbit, bitbit) * BITS_PER_LONG; - if (bitbit > maxfd) + if (bitbit >= maxfd) return maxfd; if (bitbit > start) start = bitbit; diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index c5802a459334..d46558990279 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -241,6 +241,7 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, unsigned block_size = (1 << block_bits); size_t poff = offset_in_folio(folio, *pos); size_t plen = min_t(loff_t, folio_size(folio) - poff, length); + size_t orig_plen = plen; unsigned first = poff >> block_bits; unsigned last = (poff + plen - 1) >> block_bits; @@ -277,7 +278,7 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, * handle both halves separately so that we properly zero data in the * page cache for blocks that are entirely outside of i_size. */ - if (orig_pos <= isize && orig_pos + length > isize) { + if (orig_pos <= isize && orig_pos + orig_plen > isize) { unsigned end = offset_in_folio(folio, isize - 1) >> block_bits; if (first <= end && last > end) @@ -877,22 +878,37 @@ static bool iomap_write_end(struct iomap_iter *iter, loff_t pos, size_t len, size_t copied, struct folio *folio) { const struct iomap *srcmap = iomap_iter_srcmap(iter); + loff_t old_size = iter->inode->i_size; + size_t written; if (srcmap->type == IOMAP_INLINE) { iomap_write_end_inline(iter, folio, pos, copied); - return true; - } - - if (srcmap->flags & IOMAP_F_BUFFER_HEAD) { - size_t bh_written; - - bh_written = block_write_end(NULL, iter->inode->i_mapping, pos, + written = copied; + } else if (srcmap->flags & IOMAP_F_BUFFER_HEAD) { + written = block_write_end(NULL, iter->inode->i_mapping, pos, len, copied, &folio->page, NULL); - WARN_ON_ONCE(bh_written != copied && bh_written != 0); - return bh_written == copied; + WARN_ON_ONCE(written != copied && written != 0); + } else { + written = __iomap_write_end(iter->inode, pos, len, copied, + folio) ? copied : 0; } - return __iomap_write_end(iter->inode, pos, len, copied, folio); + /* + * Update the in-memory inode size after copying the data into the page + * cache. It's up to the file system to write the updated size to disk, + * preferably after I/O completion so that no stale data is exposed. + * Only once that's done can we unlock and release the folio. + */ + if (pos + written > old_size) { + i_size_write(iter->inode, pos + written); + iter->iomap.flags |= IOMAP_F_SIZE_CHANGED; + } + __iomap_put_folio(iter, pos, written, folio); + + if (old_size < pos) + pagecache_isize_extended(iter->inode, old_size, pos); + + return written == copied; } static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i) @@ -907,7 +923,6 @@ static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i) do { struct folio *folio; - loff_t old_size; size_t offset; /* Offset into folio */ size_t bytes; /* Bytes to write to folio */ size_t copied; /* Bytes copied from user */ @@ -959,23 +974,6 @@ retry: written = iomap_write_end(iter, pos, bytes, copied, folio) ? copied : 0; - /* - * Update the in-memory inode size after copying the data into - * the page cache. It's up to the file system to write the - * updated size to disk, preferably after I/O completion so that - * no stale data is exposed. Only once that's done can we - * unlock and release the folio. - */ - old_size = iter->inode->i_size; - if (pos + written > old_size) { - i_size_write(iter->inode, pos + written); - iter->iomap.flags |= IOMAP_F_SIZE_CHANGED; - } - __iomap_put_folio(iter, pos, written, folio); - - if (old_size < pos) - pagecache_isize_extended(iter->inode, old_size, pos); - cond_resched(); if (unlikely(written == 0)) { /* @@ -1346,7 +1344,6 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter) bytes = folio_size(folio) - offset; ret = iomap_write_end(iter, pos, bytes, bytes, folio); - __iomap_put_folio(iter, pos, bytes, folio); if (WARN_ON_ONCE(!ret)) return -EIO; @@ -1412,7 +1409,6 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero) folio_mark_accessed(folio); ret = iomap_write_end(iter, pos, bytes, bytes, folio); - __iomap_put_folio(iter, pos, bytes, folio); if (WARN_ON_ONCE(!ret)) return -EIO; diff --git a/include/linux/netfs.h b/include/linux/netfs.h index 3ca3906bb8da..5d0288938cc2 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -521,7 +521,7 @@ static inline struct fscache_cookie *netfs_i_cookie(struct netfs_inode *ctx) /** * netfs_wait_for_outstanding_io - Wait for outstanding I/O to complete - * @ctx: The netfs inode to wait on + * @inode: The netfs inode to wait on * * Wait for outstanding I/O requests of any type to complete. This is intended * to be called from inode eviction routines. This makes sure that any diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h index cf4b98b9a9ed..7d931db02b93 100644 --- a/include/trace/events/cachefiles.h +++ b/include/trace/events/cachefiles.h @@ -33,6 +33,8 @@ enum cachefiles_obj_ref_trace { cachefiles_obj_see_withdrawal, cachefiles_obj_get_ondemand_fd, cachefiles_obj_put_ondemand_fd, + cachefiles_obj_get_read_req, + cachefiles_obj_put_read_req, }; enum fscache_why_object_killed { @@ -127,7 +129,11 @@ enum cachefiles_error_trace { EM(cachefiles_obj_see_lookup_cookie, "SEE lookup_cookie") \ EM(cachefiles_obj_see_lookup_failed, "SEE lookup_failed") \ EM(cachefiles_obj_see_withdraw_cookie, "SEE withdraw_cookie") \ - E_(cachefiles_obj_see_withdrawal, "SEE withdrawal") + EM(cachefiles_obj_see_withdrawal, "SEE withdrawal") \ + EM(cachefiles_obj_get_ondemand_fd, "GET ondemand_fd") \ + EM(cachefiles_obj_put_ondemand_fd, "PUT ondemand_fd") \ + EM(cachefiles_obj_get_read_req, "GET read_req") \ + E_(cachefiles_obj_put_read_req, "PUT read_req") #define cachefiles_coherency_traces \ EM(cachefiles_coherency_check_aux, "BAD aux ") \ diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h index 67626d535316..95770941ee2c 100644 --- a/include/uapi/linux/stat.h +++ b/include/uapi/linux/stat.h @@ -126,8 +126,8 @@ struct statx { __u64 stx_mnt_id; __u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */ __u32 stx_dio_offset_align; /* File offset alignment for direct I/O */ - __u64 stx_subvol; /* Subvolume identifier */ /* 0xa0 */ + __u64 stx_subvol; /* Subvolume identifier */ __u64 __spare3[11]; /* Spare space for future expansion */ /* 0x100 */ };