From cb7a95af78d29442b8294683eca4897544b8ef46 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 4 Jan 2023 11:06:28 -0800 Subject: hfs/hfsplus: avoid WARN_ON() for sanity check, use proper error handling Commit 55d1cbbbb29e ("hfs/hfsplus: use WARN_ON for sanity check") fixed a build warning by turning a comment into a WARN_ON(), but it turns out that syzbot then complains because it can trigger said warning with a corrupted hfs image. The warning actually does warn about a bad situation, but we are much better off just handling it as the error it is. So rather than warn about us doing bad things, stop doing the bad things and return -EIO. While at it, also fix a memory leak that was introduced by an earlier fix for a similar syzbot warning situation, and add a check for one case that historically wasn't handled at all (ie neither comment nor subsequent WARN_ON). Reported-by: syzbot+7bb7cd3595533513a9e7@syzkaller.appspotmail.com Fixes: 55d1cbbbb29e ("hfs/hfsplus: use WARN_ON for sanity check") Fixes: 8d824e69d9f3 ("hfs: fix OOB Read in __hfs_brec_find") Link: https://lore.kernel.org/lkml/000000000000dbce4e05f170f289@google.com/ Tested-by: Michael Schmitz Cc: Arnd Bergmann Cc: Matthew Wilcox Cc: Viacheslav Dubeyko Signed-off-by: Linus Torvalds --- fs/hfs/inode.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'fs/hfs') diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c index 9c329a365e75..3a155c1d810e 100644 --- a/fs/hfs/inode.c +++ b/fs/hfs/inode.c @@ -458,15 +458,16 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc) /* panic? */ return -EIO; + res = -EIO; if (HFS_I(main_inode)->cat_key.CName.len > HFS_NAMELEN) - return -EIO; + goto out; fd.search_key->cat = HFS_I(main_inode)->cat_key; if (hfs_brec_find(&fd)) - /* panic? */ goto out; if (S_ISDIR(main_inode->i_mode)) { - WARN_ON(fd.entrylength < sizeof(struct hfs_cat_dir)); + if (fd.entrylength < sizeof(struct hfs_cat_dir)) + goto out; hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_dir)); if (rec.type != HFS_CDR_DIR || @@ -479,6 +480,8 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc) hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_dir)); } else if (HFS_IS_RSRC(inode)) { + if (fd.entrylength < sizeof(struct hfs_cat_file)) + goto out; hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_file)); hfs_inode_write_fork(inode, rec.file.RExtRec, @@ -486,7 +489,8 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc) hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_file)); } else { - WARN_ON(fd.entrylength < sizeof(struct hfs_cat_file)); + if (fd.entrylength < sizeof(struct hfs_cat_file)) + goto out; hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_file)); if (rec.type != HFS_CDR_FIL || @@ -503,9 +507,10 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc) hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, sizeof(struct hfs_cat_file)); } + res = 0; out: hfs_find_exit(&fd); - return 0; + return res; } static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry, -- cgit