From: Linus Torvalds torvalds@linux-foundation.org
commit cb7a95af78d29442b8294683eca4897544b8ef46 upstream.
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 schmitzmic@gmail.com Cc: Arnd Bergmann arnd@arndb.de Cc: Matthew Wilcox willy@infradead.org Cc: Viacheslav Dubeyko slava@dubeyko.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/hfs/inode.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
--- a/fs/hfs/inode.c +++ b/fs/hfs/inode.c @@ -454,15 +454,16 @@ int hfs_write_inode(struct inode *inode, /* 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 || @@ -475,6 +476,8 @@ int hfs_write_inode(struct inode *inode, 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, @@ -482,7 +485,8 @@ int hfs_write_inode(struct inode *inode, 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 || @@ -499,9 +503,10 @@ int hfs_write_inode(struct inode *inode, 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,