From 2b462638e41ea62230297c21c4da9955937b7a3c Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Fri, 29 Aug 2014 15:18:58 -0700 Subject: ocfs2: do not write error flag to user structure we cannot copy from/to 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 --- 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 6f66b37..53e6c40 100644 --- a/fs/ocfs2/ioctl.c +++ b/fs/ocfs2/ioctl.c @@ -35,9 +35,8 @@ 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) @@ -146,136 +145,105 @@ bail: static 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; } static 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; } static 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; } static 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; } static 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; } static 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; @@ -284,39 +252,28 @@ static 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; } static 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 = i_size_read(osb->journal->j_inode); 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; } static int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb, @@ -373,7 +330,7 @@ static 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; @@ -385,8 +342,10 @@ static 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; @@ -424,14 +383,16 @@ static 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; @@ -658,7 +619,7 @@ static 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); @@ -671,8 +632,10 @@ static 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. */ @@ -711,14 +674,14 @@ static 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; @@ -727,23 +690,17 @@ out_err: static 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; } /* -- cgit v1.1