diff options
| author | Norbert Szetei <norbert@doyensec.com> | 2025-05-02 08:21:58 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-05-18 08:24:47 +0200 |
| commit | d62ba16563a86aae052f96d270b3b6f78fca154c (patch) | |
| tree | cf7a276f82418f5107e469efa896ea0fd1686f19 | |
| parent | c57301e332cc413fe0a7294a90725f4e21e9549d (diff) | |
ksmbd: prevent out-of-bounds stream writes by validating *pos
commit 0ca6df4f40cf4c32487944aaf48319cb6c25accc upstream.
ksmbd_vfs_stream_write() did not validate whether the write offset
(*pos) was within the bounds of the existing stream data length (v_len).
If *pos was greater than or equal to v_len, this could lead to an
out-of-bounds memory write.
This patch adds a check to ensure *pos is less than v_len before
proceeding. If the condition fails, -EINVAL is returned.
Cc: stable@vger.kernel.org
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/smb/server/vfs.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c index a7694aae0b947..e059316be36fd 100644 --- a/fs/smb/server/vfs.c +++ b/fs/smb/server/vfs.c @@ -443,6 +443,13 @@ static int ksmbd_vfs_stream_write(struct ksmbd_file *fp, char *buf, loff_t *pos, goto out; } + if (v_len <= *pos) { + pr_err("stream write position %lld is out of bounds (stream length: %zd)\n", + *pos, v_len); + err = -EINVAL; + goto out; + } + if (v_len < size) { wbuf = kvzalloc(size, KSMBD_DEFAULT_GFP); if (!wbuf) { |