[src/trunk]: src/sys/dev/i2c Allocate data buffer instead of using the stack.

[mlelstv <mlelstv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/63aaeaabd8e5
branches:  trunk
changeset: 368215:63aaeaabd8e5
user:      mlelstv <mlelstv%NetBSD.org@localhost>
date:      Wed Jun 29 15:33:45 2022 +0000

description:
Allocate data buffer instead of using the stack.

diffstat:

 sys/dev/i2c/i2c.c |  26 ++++++++++++++++----------
 1 files changed, 16 insertions(+), 10 deletions(-)

diffs (67 lines):

diff -r 1e7e2d885ef1 -r 63aaeaabd8e5 sys/dev/i2c/i2c.c
--- a/sys/dev/i2c/i2c.c Wed Jun 29 13:03:20 2022 +0000
+++ b/sys/dev/i2c/i2c.c Wed Jun 29 15:33:45 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: i2c.c,v 1.86 2022/04/01 15:49:12 pgoyette Exp $        */
+/*     $NetBSD: i2c.c,v 1.87 2022/06/29 15:33:45 mlelstv Exp $ */
 
 /*
  * Copyright (c) 2003 Wasabi Systems, Inc.
@@ -53,7 +53,7 @@
 #endif /* _KERNEL_OPT */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: i2c.c,v 1.86 2022/04/01 15:49:12 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: i2c.c,v 1.87 2022/06/29 15:33:45 mlelstv Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -819,7 +819,7 @@
 iic_ioctl_exec(struct iic_softc *sc, i2c_ioctl_exec_t *iie, int flag)
 {
        i2c_tag_t ic = sc->sc_tag;
-       uint8_t buf[I2C_EXEC_MAX_BUFLEN];
+       uint8_t *buf = NULL;
        void *cmd = NULL;
        int error;
 
@@ -849,10 +849,13 @@
                        goto out;
        }
 
-       if (iie->iie_buf != NULL && I2C_OP_WRITE_P(iie->iie_op)) {
-               error = copyin(iie->iie_buf, buf, iie->iie_buflen);
-               if (error)
-                       goto out;
+       if (iie->iie_buf != NULL) {
+               buf = kmem_alloc(iie->iie_buflen, KM_SLEEP);
+               if (I2C_OP_WRITE_P(iie->iie_op)) {
+                       error = copyin(iie->iie_buf, buf, iie->iie_buflen);
+                       if (error)
+                               goto out;
+               }
        }
 
        iic_acquire_bus(ic, 0);
@@ -867,15 +870,18 @@
                error = EIO;
 
 out:
+       if (iie->iie_buf != NULL && I2C_OP_READ_P(iie->iie_op))
+               error = copyout(buf, iie->iie_buf, iie->iie_buflen);
+
+       if (buf)
+               kmem_free(buf, iie->iie_buflen);
+
        if (cmd)
                kmem_free(cmd, iie->iie_cmdlen);
 
        if (error)
                return error;
 
-       if (iie->iie_buf != NULL && I2C_OP_READ_P(iie->iie_op))
-               error = copyout(buf, iie->iie_buf, iie->iie_buflen);
-
        return error;
 }