From ce9504998a5a45f49f21dc744eb805a96fb7b617 Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Sat, 23 Mar 2019 15:42:31 +0800 Subject: [PATCH] CIFS: Fix error paths in writeback code CIFS: Fix leaking locked VFS cache pages in writeback retry mainline inclusion from mainline-v5.0-rc2 commit 9a66396f1857cc1de06f4f4771797315e1a4ea56 category: bugfix bugzilla: 12058 CVE: NA ------------------------------------------------- This patch aims to address writeback code problems related to error paths. In particular it respects EINTR and related error codes and stores and returns the first error occurred during writeback. Signed-off-by: Pavel Shilovsky Acked-by: Jeff Layton Signed-off-by: Steve French Signed-off-by: ZhangXiaoxu Reviewed-by: zhengbin Signed-off-by: Yang Yingliang --- fs/cifs/cifsglob.h | 19 +++++++++++++++++++ fs/cifs/cifssmb.c | 7 ++++--- fs/cifs/file.c | 29 +++++++++++++++++++++++------ fs/cifs/inode.c | 10 ++++++++++ 4 files changed, 56 insertions(+), 9 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 80f33582059e..336a71aa22be 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1562,6 +1562,25 @@ static inline void free_dfs_info_array(struct dfs_info3_param *param, kfree(param); } +static inline bool is_interrupt_error(int error) +{ + switch (error) { + case -EINTR: + case -ERESTARTSYS: + case -ERESTARTNOHAND: + case -ERESTARTNOINTR: + return true; + } + return false; +} + +static inline bool is_retryable_error(int error) +{ + if (is_interrupt_error(error) || error == -EAGAIN) + return true; + return false; +} + #define MID_FREE 0 #define MID_REQUEST_ALLOCATED 1 #define MID_REQUEST_SUBMITTED 2 diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 269471c8f42b..a5cb7b2d1ac5 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -2042,7 +2042,7 @@ cifs_writev_requeue(struct cifs_writedata *wdata) for (j = 0; j < nr_pages; j++) { unlock_page(wdata2->pages[j]); - if (rc != 0 && rc != -EAGAIN) { + if (rc != 0 && !is_retryable_error(rc)) { SetPageError(wdata2->pages[j]); end_page_writeback(wdata2->pages[j]); put_page(wdata2->pages[j]); @@ -2051,7 +2051,7 @@ cifs_writev_requeue(struct cifs_writedata *wdata) if (rc) { kref_put(&wdata2->refcount, cifs_writedata_release); - if (rc == -EAGAIN) + if (is_retryable_error(rc)) continue; break; } @@ -2060,7 +2060,8 @@ cifs_writev_requeue(struct cifs_writedata *wdata) i += nr_pages; } while (i < wdata->nr_pages); - mapping_set_error(inode->i_mapping, rc); + if (rc != 0 && !is_retryable_error(rc)) + mapping_set_error(inode->i_mapping, rc); kref_put(&wdata->refcount, cifs_writedata_release); } diff --git a/fs/cifs/file.c b/fs/cifs/file.c index a48769666232..a1062b37b461 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -730,7 +730,8 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush) if (can_flush) { rc = filemap_write_and_wait(inode->i_mapping); - mapping_set_error(inode->i_mapping, rc); + if (!is_interrupt_error(rc)) + mapping_set_error(inode->i_mapping, rc); if (tcon->unix_ext) rc = cifs_get_inode_info_unix(&inode, full_path, @@ -2118,6 +2119,7 @@ static int cifs_writepages(struct address_space *mapping, pgoff_t end, index; struct cifs_writedata *wdata; int rc = 0; + int saved_rc = 0; unsigned int xid; /* @@ -2146,8 +2148,10 @@ static int cifs_writepages(struct address_space *mapping, rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize, &wsize, &credits); - if (rc) + if (rc != 0) { + done = true; break; + } tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1; @@ -2155,6 +2159,7 @@ static int cifs_writepages(struct address_space *mapping, &found_pages); if (!wdata) { rc = -ENOMEM; + done = true; add_credits_and_wake_if(server, credits, 0); break; } @@ -2183,7 +2188,7 @@ static int cifs_writepages(struct address_space *mapping, if (rc != 0) { add_credits_and_wake_if(server, wdata->credits, 0); for (i = 0; i < nr_pages; ++i) { - if (rc == -EAGAIN) + if (is_retryable_error(rc)) redirty_page_for_writepage(wbc, wdata->pages[i]); else @@ -2191,7 +2196,7 @@ static int cifs_writepages(struct address_space *mapping, end_page_writeback(wdata->pages[i]); put_page(wdata->pages[i]); } - if (rc != -EAGAIN) + if (!is_retryable_error(rc)) mapping_set_error(mapping, rc); } kref_put(&wdata->refcount, cifs_writedata_release); @@ -2201,6 +2206,15 @@ static int cifs_writepages(struct address_space *mapping, continue; } + /* Return immediately if we received a signal during writing */ + if (is_interrupt_error(rc)) { + done = true; + break; + } + + if (rc != 0 && saved_rc == 0) + saved_rc = rc; + wbc->nr_to_write -= nr_pages; if (wbc->nr_to_write <= 0) done = true; @@ -2218,6 +2232,9 @@ static int cifs_writepages(struct address_space *mapping, goto retry; } + if (saved_rc != 0) + rc = saved_rc; + if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) mapping->writeback_index = index; @@ -2250,8 +2267,8 @@ cifs_writepage_locked(struct page *page, struct writeback_control *wbc) set_page_writeback(page); retry_write: rc = cifs_partialpagewrite(page, 0, PAGE_SIZE); - if (rc == -EAGAIN) { - if (wbc->sync_mode == WB_SYNC_ALL) + if (is_retryable_error(rc)) { + if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) goto retry_write; redirty_page_for_writepage(wbc, page); } else if (rc != 0) { diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index 020f49c15b30..67eef155a33f 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -2250,6 +2250,11 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs) * the flush returns error? */ rc = filemap_write_and_wait(inode->i_mapping); + if (is_interrupt_error(rc)) { + rc = -ERESTARTSYS; + goto out; + } + mapping_set_error(inode->i_mapping, rc); rc = 0; @@ -2393,6 +2398,11 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs) * the flush returns error? */ rc = filemap_write_and_wait(inode->i_mapping); + if (is_interrupt_error(rc)) { + rc = -ERESTARTSYS; + goto cifs_setattr_exit; + } + mapping_set_error(inode->i_mapping, rc); rc = 0; -- GitLab