Re: [Fwd: [PATCH 1/2] string: Add stracpy and stracpy_pad mechanisms]

From: Joe Perches
Date: Wed Jul 24 2019 - 00:20:06 EST


On Tue, 2019-07-23 at 22:54 -0500, Julia Lawall wrote:
> A seantic patch and the resulting output for the case where the third
> arugument is a constant is attached. Likewise the resulting output on a
> recent linux-next.
>
> julia

Nice. Thanks Julia

A couple issues:

There is a problem with conversions with assignments
of strlcpy() so ideally the cocci script should make sure
any return value was not used before conversion.

This is not a provably good conversion:

drivers/s390/char/sclp_ftp.c
@@ -114,8 +114,7 @@ static int sclp_ftp_et7(const struct hmc
sccb->evbuf.mdd.ftp.length = ftp->len;
sccb->evbuf.mdd.ftp.bufaddr = virt_to_phys(ftp->buf);

- len = strlcpy(sccb->evbuf.mdd.ftp.fident, ftp->fname,
- HMCDRV_FTP_FIDENT_MAX);
+ len = stracpy(sccb->evbuf.mdd.ftp.fident, ftp->fname);

And:

I would have expected the bit below to find and convert uses like
drivers/hwmon/adc128d818.c: strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
but it seems none of those were converted.

I don't know why.

//------------------------------------------
@r1@
struct i1 *e1;
expression e2;
identifier f,i1,i2;
position p;
@@
\(strscpy\|strlcpy\)(e1->f, e2, i2)@p

@@
identifier r1.i1,r1.i2;
type T;
@@
struct i1 { ... T i1[i2]; ... }

@@
identifier f,i2;
expression e1,e2;
position r1.p;
@@
(
-strscpy
+stracpy
|
-strlcpy
+stracpy
)(e1->f, e2
- , i2
)@p
//------------------------------------------

to find