From: Kyle Zeng <kylebot@openai.com> stable inclusion from stable-v5.10.270 commit 33cda0036bc683fc888c20b04a5fc030e3e8413b category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19167 CVE: CVE-2026-93095 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit e2ea5cac61acfc11dad22f1d2d4bc71d56c52a20 ] hfsplus_delete_cat() is called with str == NULL when the last open reference to an unlinked HFS+ hardlink backing inode is closed. In that case, the function finds the catalog thread by CNID and rebuilds the catalog key from thread.nodeName. That reconstruction path reads thread.nodeName.length directly from the catalog B-tree into fd.search_key and then copies length * 2 bytes into fd.search_key->cat.name.unicode. It does not first check that the found record is a thread record or that its size matches the thread name. A corrupted image can therefore provide an oversized thread name length and make hfs_bnode_read() write past the catalog search-key allocation. Read the CNID record through hfsplus_brec_read_cat(), which bounds the record read to sizeof(hfsplus_cat_entry) and verifies that a thread record's size exactly matches nodeName.length. Together, these checks ensure an accepted thread name fits HFSPLUS_MAX_STRLEN. Reject non-thread records before building the delete key from the validated thread name. Share the thread-record-type helper between hfsplus_find_cat() and hfsplus_delete_cat(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Assisted-by: Codex:gpt-5.6 Signed-off-by: Kyle Zeng <kylebot@openai.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> Link: https://lore.kernel.org/r/20260709010203.49664-1-kylebot@openai.com Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Tengda Wu <wutengda2@huawei.com> --- fs/hfsplus/catalog.c | 25 ++++++++++++------------- fs/hfsplus/hfsplus_fs.h | 6 ++++++ 2 files changed, 18 insertions(+), 13 deletions(-) diff --git a/fs/hfsplus/catalog.c b/fs/hfsplus/catalog.c index 136aa1017af2..9a82bdf4caf2 100644 --- a/fs/hfsplus/catalog.c +++ b/fs/hfsplus/catalog.c @@ -204,7 +204,7 @@ int hfsplus_find_cat(struct super_block *sb, u32 cnid, return err; type = be16_to_cpu(tmp.type); - if (type != HFSPLUS_FOLDER_THREAD && type != HFSPLUS_FILE_THREAD) { + if (!is_hfs_thread_record_type(type)) { pr_err("found bad thread record in catalog\n"); return -EIO; } @@ -350,23 +350,22 @@ int hfsplus_delete_cat(u32 cnid, struct inode *dir, const struct qstr *str) goto out; if (!str) { - int len; + hfsplus_cat_entry entry = {0}; hfsplus_cat_build_key_with_cnid(sb, fd.search_key, cnid); - err = hfs_brec_find(&fd, hfs_find_rec_by_key); + err = hfsplus_brec_read_cat(&fd, &entry); if (err) goto out; - off = fd.entryoffset + - offsetof(struct hfsplus_cat_thread, nodeName); - fd.search_key->cat.parent = cpu_to_be32(dir->i_ino); - hfs_bnode_read(fd.bnode, - &fd.search_key->cat.name.length, off, 2); - len = be16_to_cpu(fd.search_key->cat.name.length) * 2; - hfs_bnode_read(fd.bnode, - &fd.search_key->cat.name.unicode, - off + 2, len); - fd.search_key->key_len = cpu_to_be16(6 + len); + type = be16_to_cpu(entry.type); + if (!is_hfs_thread_record_type(type)) { + pr_err("found bad thread record in catalog\n"); + err = -EIO; + goto out; + } + + hfsplus_cat_build_key_uni(fd.search_key, dir->i_ino, + &entry.thread.nodeName); } else { err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, str); if (unlikely(err)) diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h index 239e8cfb0314..a572ea1869d6 100644 --- a/fs/hfsplus/hfsplus_fs.h +++ b/fs/hfsplus/hfsplus_fs.h @@ -547,6 +547,12 @@ static inline u32 hfsplus_cat_thread_size(const struct hfsplus_cat_thread *threa be16_to_cpu(thread->nodeName.length) * sizeof(hfsplus_unichr); } +static inline +bool is_hfs_thread_record_type(u16 type) +{ + return type == HFSPLUS_FOLDER_THREAD || type == HFSPLUS_FILE_THREAD; +} + int hfsplus_brec_read_cat(struct hfs_find_data *fd, hfsplus_cat_entry *entry); /* -- 2.34.1