Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753761AbdFGXGj (ORCPT ); Wed, 7 Jun 2017 19:06:39 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:50871 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752891AbdFGXGg (ORCPT ); Wed, 7 Jun 2017 19:06:36 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Ben Hutchings , Joel Becker , Andrew Morton , Linus Torvalds , Jiri Slaby , Willy Tarreau Subject: [PATCH 3.10 135/250] ocfs2: do not write error flag to user structure we cannot copy from/to Date: Thu, 8 Jun 2017 00:58:41 +0200 Message-Id: <1496876436-32402-136-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1496876436-32402-1-git-send-email-w@1wt.eu> References: <1496876436-32402-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8202 Lines: 349 From: Ben Hutchings commit 2b462638e41ea62230297c21c4da9955937b7a3c upstream. If we failed to copy from the structure, writing back the flags leaks 31 bits of kernel memory (the rest of the ir_flags field). In any case, if we cannot copy from/to the structure, why should we expect putting just the flags to work? Also make sure ocfs2_info_handle_freeinode() returns the right error code if the copy_to_user() fails. Fixes: ddee5cdb70e6 ('Ocfs2: Add new OCFS2_IOC_INFO ioctl for ocfs2 v8.') Signed-off-by: Ben Hutchings Cc: Joel Becker Acked-by: Mark Fasheh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Jiri Slaby Signed-off-by: Willy Tarreau --- fs/ocfs2/ioctl.c | 129 +++++++++++++++++++------------------------------------ 1 file changed, 43 insertions(+), 86 deletions(-) diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c index 0c60ef2..b9d1609 100644 --- a/fs/ocfs2/ioctl.c +++ b/fs/ocfs2/ioctl.c @@ -34,9 +34,8 @@ copy_to_user((typeof(a) __user *)b, &(a), sizeof(a)) /* - * This call is void because we are already reporting an error that may - * be -EFAULT. The error will be returned from the ioctl(2) call. It's - * just a best-effort to tell userspace that this request caused the error. + * This is just a best-effort to tell userspace that this request + * caused the error. */ static inline void o2info_set_request_error(struct ocfs2_info_request *kreq, struct ocfs2_info_request __user *req) @@ -145,136 +144,105 @@ bail: int ocfs2_info_handle_blocksize(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_blocksize oib; if (o2info_from_user(oib, req)) - goto bail; + return -EFAULT; oib.ib_blocksize = inode->i_sb->s_blocksize; o2info_set_request_filled(&oib.ib_req); if (o2info_to_user(oib, req)) - goto bail; - - status = 0; -bail: - if (status) - o2info_set_request_error(&oib.ib_req, req); + return -EFAULT; - return status; + return 0; } int ocfs2_info_handle_clustersize(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_clustersize oic; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oic, req)) - goto bail; + return -EFAULT; oic.ic_clustersize = osb->s_clustersize; o2info_set_request_filled(&oic.ic_req); if (o2info_to_user(oic, req)) - goto bail; - - status = 0; -bail: - if (status) - o2info_set_request_error(&oic.ic_req, req); + return -EFAULT; - return status; + return 0; } int ocfs2_info_handle_maxslots(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_maxslots oim; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oim, req)) - goto bail; + return -EFAULT; oim.im_max_slots = osb->max_slots; o2info_set_request_filled(&oim.im_req); if (o2info_to_user(oim, req)) - goto bail; + return -EFAULT; - status = 0; -bail: - if (status) - o2info_set_request_error(&oim.im_req, req); - - return status; + return 0; } int ocfs2_info_handle_label(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_label oil; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oil, req)) - goto bail; + return -EFAULT; memcpy(oil.il_label, osb->vol_label, OCFS2_MAX_VOL_LABEL_LEN); o2info_set_request_filled(&oil.il_req); if (o2info_to_user(oil, req)) - goto bail; + return -EFAULT; - status = 0; -bail: - if (status) - o2info_set_request_error(&oil.il_req, req); - - return status; + return 0; } int ocfs2_info_handle_uuid(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_uuid oiu; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oiu, req)) - goto bail; + return -EFAULT; memcpy(oiu.iu_uuid_str, osb->uuid_str, OCFS2_TEXT_UUID_LEN + 1); o2info_set_request_filled(&oiu.iu_req); if (o2info_to_user(oiu, req)) - goto bail; - - status = 0; -bail: - if (status) - o2info_set_request_error(&oiu.iu_req, req); + return -EFAULT; - return status; + return 0; } int ocfs2_info_handle_fs_features(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_fs_features oif; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oif, req)) - goto bail; + return -EFAULT; oif.if_compat_features = osb->s_feature_compat; oif.if_incompat_features = osb->s_feature_incompat; @@ -283,39 +251,28 @@ int ocfs2_info_handle_fs_features(struct inode *inode, o2info_set_request_filled(&oif.if_req); if (o2info_to_user(oif, req)) - goto bail; + return -EFAULT; - status = 0; -bail: - if (status) - o2info_set_request_error(&oif.if_req, req); - - return status; + return 0; } int ocfs2_info_handle_journal_size(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_journal_size oij; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (o2info_from_user(oij, req)) - goto bail; + return -EFAULT; oij.ij_journal_size = osb->journal->j_inode->i_size; o2info_set_request_filled(&oij.ij_req); if (o2info_to_user(oij, req)) - goto bail; + return -EFAULT; - status = 0; -bail: - if (status) - o2info_set_request_error(&oij.ij_req, req); - - return status; + return 0; } int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb, @@ -371,7 +328,7 @@ int ocfs2_info_handle_freeinode(struct inode *inode, u32 i; u64 blkno = -1; char namebuf[40]; - int status = -EFAULT, type = INODE_ALLOC_SYSTEM_INODE; + int status, type = INODE_ALLOC_SYSTEM_INODE; struct ocfs2_info_freeinode *oifi = NULL; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); struct inode *inode_alloc = NULL; @@ -383,8 +340,10 @@ int ocfs2_info_handle_freeinode(struct inode *inode, goto out_err; } - if (o2info_from_user(*oifi, req)) - goto bail; + if (o2info_from_user(*oifi, req)) { + status = -EFAULT; + goto out_free; + } oifi->ifi_slotnum = osb->max_slots; @@ -421,14 +380,16 @@ int ocfs2_info_handle_freeinode(struct inode *inode, o2info_set_request_filled(&oifi->ifi_req); - if (o2info_to_user(*oifi, req)) - goto bail; + if (o2info_to_user(*oifi, req)) { + status = -EFAULT; + goto out_free; + } status = 0; bail: if (status) o2info_set_request_error(&oifi->ifi_req, req); - +out_free: kfree(oifi); out_err: return status; @@ -655,7 +616,7 @@ int ocfs2_info_handle_freefrag(struct inode *inode, { u64 blkno = -1; char namebuf[40]; - int status = -EFAULT, type = GLOBAL_BITMAP_SYSTEM_INODE; + int status, type = GLOBAL_BITMAP_SYSTEM_INODE; struct ocfs2_info_freefrag *oiff; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); @@ -668,8 +629,10 @@ int ocfs2_info_handle_freefrag(struct inode *inode, goto out_err; } - if (o2info_from_user(*oiff, req)) - goto bail; + if (o2info_from_user(*oiff, req)) { + status = -EFAULT; + goto out_free; + } /* * chunksize from userspace should be power of 2. */ @@ -708,14 +671,14 @@ int ocfs2_info_handle_freefrag(struct inode *inode, if (o2info_to_user(*oiff, req)) { status = -EFAULT; - goto bail; + goto out_free; } status = 0; bail: if (status) o2info_set_request_error(&oiff->iff_req, req); - +out_free: kfree(oiff); out_err: return status; @@ -724,23 +687,17 @@ out_err: int ocfs2_info_handle_unknown(struct inode *inode, struct ocfs2_info_request __user *req) { - int status = -EFAULT; struct ocfs2_info_request oir; if (o2info_from_user(oir, req)) - goto bail; + return -EFAULT; o2info_clear_request_filled(&oir); if (o2info_to_user(oir, req)) - goto bail; + return -EFAULT; - status = 0; -bail: - if (status) - o2info_set_request_error(&oir, req); - - return status; + return 0; } /* -- 2.8.0.rc2.1.gbe9624a