6.1-stable review patch. If anyone has any objections, please let me know.
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From: Zeng Heng zengheng4@huawei.com
commit 8e7e27b2ee1e19c4040d4987e345f678a74c0aed upstream.
Here is a BUG report about linux-6.1 from syzbot, but it still remains within upstream:
BUG: KASAN: slab-out-of-bounds in ntfs_list_ea fs/ntfs3/xattr.c:191 [inline] BUG: KASAN: slab-out-of-bounds in ntfs_listxattr+0x401/0x570 fs/ntfs3/xattr.c:710 Read of size 1 at addr ffff888021acaf3d by task syz-executor128/3632
Call Trace: kasan_report+0x139/0x170 mm/kasan/report.c:495 ntfs_list_ea fs/ntfs3/xattr.c:191 [inline] ntfs_listxattr+0x401/0x570 fs/ntfs3/xattr.c:710 vfs_listxattr fs/xattr.c:457 [inline] listxattr+0x293/0x2d0 fs/xattr.c:804 path_listxattr fs/xattr.c:828 [inline] __do_sys_llistxattr fs/xattr.c:846 [inline]
Before derefering field members of `ea` in unpacked_ea_size(), we need to check whether the EA_FULL struct is located in access validate range.
Similarly, when derefering `ea->name` field member, we need to check whethe the ea->name is located in access validate range, too.
Fixes: be71b5cba2e6 ("fs/ntfs3: Add attrib operations") Reported-by: syzbot+9fcea5ef6dc4dc72d334@syzkaller.appspotmail.com Signed-off-by: Zeng Heng zengheng4@huawei.com [almaz.alexandrovich@paragon-software.com: took the ret variable out of the loop block] Signed-off-by: Konstantin Komarov almaz.alexandrovich@paragon-software.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ntfs3/xattr.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
--- a/fs/ntfs3/xattr.c +++ b/fs/ntfs3/xattr.c @@ -209,7 +209,8 @@ static ssize_t ntfs_list_ea(struct ntfs_ size = le32_to_cpu(info->size);
/* Enumerate all xattrs. */ - for (ret = 0, off = 0; off < size; off += ea_size) { + ret = 0; + for (off = 0; off + sizeof(struct EA_FULL) < size; off += ea_size) { ea = Add2Ptr(ea_all, off); ea_size = unpacked_ea_size(ea);
@@ -217,6 +218,10 @@ static ssize_t ntfs_list_ea(struct ntfs_ break;
if (buffer) { + /* Check if we can use field ea->name */ + if (off + ea_size > size) + break; + if (ret + ea->name_len + 1 > bytes_per_buffer) { err = -ERANGE; goto out;