From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp

[ Upstream commit 81b21c0f0138ff5a499eafc3eb0578ad2a99622c ]

syzbot is hitting WARN_ON() in hfsplus_cat_{read,write}_inode(), for crafted filesystem image can contain bogus length. There conditions are not kernel bugs that can justify kernel to panic.

Reported-by: syzbot syzbot+e2787430e752a92b8750@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=e2787430e752a92b8750 Reported-by: syzbot syzbot+4913dca2ea6e4d43f3f1@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=4913dca2ea6e4d43f3f1 Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Reviewed-by: Viacheslav Dubeyko slava@dubeyko.com Message-Id: 15308173-5252-d6a3-ae3b-e96d46cb6f41@I-love.SAKURA.ne.jp Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/hfsplus/inode.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index 76501d905099b..15c14a6a9f7fe 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -497,7 +497,11 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd) if (type == HFSPLUS_FOLDER) { struct hfsplus_cat_folder *folder = &entry.folder;

- WARN_ON(fd->entrylength < sizeof(struct hfsplus_cat_folder)); + if (fd->entrylength < sizeof(struct hfsplus_cat_folder)) { + pr_err("bad catalog folder entry\n"); + res = -EIO; + goto out; + } hfs_bnode_read(fd->bnode, &entry, fd->entryoffset, sizeof(struct hfsplus_cat_folder)); hfsplus_get_perms(inode, &folder->permissions, 1); @@ -517,7 +521,11 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd) } else if (type == HFSPLUS_FILE) { struct hfsplus_cat_file *file = &entry.file;

- WARN_ON(fd->entrylength < sizeof(struct hfsplus_cat_file)); + if (fd->entrylength < sizeof(struct hfsplus_cat_file)) { + pr_err("bad catalog file entry\n"); + res = -EIO; + goto out; + } hfs_bnode_read(fd->bnode, &entry, fd->entryoffset, sizeof(struct hfsplus_cat_file));

@@ -548,6 +556,7 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd) pr_err("bad catalog entry used to create inode\n"); res = -EIO; } +out: return res; }

@@ -556,6 +565,7 @@ int hfsplus_cat_write_inode(struct inode *inode) struct inode *main_inode = inode; struct hfs_find_data fd; hfsplus_cat_entry entry; + int res = 0;

if (HFSPLUS_IS_RSRC(inode)) main_inode = HFSPLUS_I(inode)->rsrc_inode; @@ -574,7 +584,11 @@ int hfsplus_cat_write_inode(struct inode *inode) if (S_ISDIR(main_inode->i_mode)) { struct hfsplus_cat_folder *folder = &entry.folder;

- WARN_ON(fd.entrylength < sizeof(struct hfsplus_cat_folder)); + if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) { + pr_err("bad catalog folder entry\n"); + res = -EIO; + goto out; + } hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, sizeof(struct hfsplus_cat_folder)); /* simple node checks? */ @@ -599,7 +613,11 @@ int hfsplus_cat_write_inode(struct inode *inode) } else { struct hfsplus_cat_file *file = &entry.file;

- WARN_ON(fd.entrylength < sizeof(struct hfsplus_cat_file)); + if (fd.entrylength < sizeof(struct hfsplus_cat_file)) { + pr_err("bad catalog file entry\n"); + res = -EIO; + goto out; + } hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, sizeof(struct hfsplus_cat_file)); hfsplus_inode_write_fork(inode, &file->data_fork); @@ -620,5 +638,5 @@ int hfsplus_cat_write_inode(struct inode *inode) set_bit(HFSPLUS_I_CAT_DIRTY, &HFSPLUS_I(inode)->flags); out: hfs_find_exit(&fd); - return 0; + return res; }