diff options
author | Randall Huang <huangrandall@google.com> | 2019-10-18 09:56:22 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-05-20 09:17:04 +0300 |
commit | ae811cecbbb231f11a84acaf74baca1283b964c7 (patch) | |
tree | 25c5bf8a3c91eec3bd0031c19f582e29079ee176 /fs/f2fs | |
parent | 1d295b32df866ea09aa8cc94500ed6e96e2ea09e (diff) | |
download | linux-ae811cecbbb231f11a84acaf74baca1283b964c7.tar.xz |
f2fs: fix to avoid memory leakage in f2fs_listxattr
commit 688078e7f36c293dae25b338ddc9e0a2790f6e06 upstream.
In f2fs_listxattr, there is no boundary check before
memcpy e_name to buffer.
If the e_name_len is corrupted,
unexpected memory contents may be returned to the buffer.
Signed-off-by: Randall Huang <huangrandall@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
[bwh: Backported to 4.14: Use f2fs_msg() instead of f2fs_err()]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/f2fs')
-rw-r--r-- | fs/f2fs/xattr.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c index 0998a6c75cad..89c975126d4e 100644 --- a/fs/f2fs/xattr.c +++ b/fs/f2fs/xattr.c @@ -516,8 +516,9 @@ out: ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) { struct inode *inode = d_inode(dentry); + nid_t xnid = F2FS_I(inode)->i_xattr_nid; struct f2fs_xattr_entry *entry; - void *base_addr; + void *base_addr, *last_base_addr; int error = 0; size_t rest = buffer_size; @@ -527,6 +528,8 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) if (error) return error; + last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode); + list_for_each_xattr(entry, base_addr) { const struct xattr_handler *handler = f2fs_xattr_handler(entry->e_name_index); @@ -534,6 +537,16 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) size_t prefix_len; size_t size; + if ((void *)(entry) + sizeof(__u32) > last_base_addr || + (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) { + f2fs_msg(dentry->d_sb, KERN_ERR, + "inode (%lu) has corrupted xattr", + inode->i_ino); + set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK); + error = -EFSCORRUPTED; + goto cleanup; + } + if (!handler || (handler->list && !handler->list(dentry))) continue; |