From: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com
[ Upstream commit 64c4a37ac04eeb43c42d272f6e6c8c12bfcf4304 ]
Smatch printed a warning: arch/x86/crypto/poly1305_glue.c:198 poly1305_update_arch() error: __memcpy() 'dctx->buf' too small (16 vs u32max)
It's caused because Smatch marks 'link_len' as untrusted since it comes from sscanf(). Add a check to ensure that 'link_len' is not larger than the size of the 'link_str' buffer.
Fixes: c69c1b6eaea1 ("cifs: implement CIFSParseMFSymlink()") Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com Reviewed-by: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cifs/link.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 2148b0f60e5e..5b1c33d9283a 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -97,6 +97,9 @@ parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len, if (rc != 1) return -EINVAL;
+ if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN) + return -EINVAL; + rc = symlink_hash(link_len, link_str, md5_hash); if (rc) { cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);