[src/trunk]: src/sys/external/bsd/drm/dist/bsd-core fix the DRM string sysctl...

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

details:   https://anonhg.NetBSD.org/src/rev/68b1c697871c
branches:  trunk
changeset: 781771:68b1c697871c
user:      chs <chs%NetBSD.org@localhost>
date:      Sat Sep 29 14:19:43 2012 +0000

description:
fix the DRM string sysctls to use copyout() instead of strcat()
to deliver the data to the user buffer.

diffstat:

 sys/external/bsd/drm/dist/bsd-core/drm_sysctl.c |  62 ++++++++++++++++++++++--
 1 files changed, 57 insertions(+), 5 deletions(-)

diffs (100 lines):

diff -r 9be89df13a47 -r 68b1c697871c sys/external/bsd/drm/dist/bsd-core/drm_sysctl.c
--- a/sys/external/bsd/drm/dist/bsd-core/drm_sysctl.c   Sat Sep 29 12:03:41 2012 +0000
+++ b/sys/external/bsd/drm/dist/bsd-core/drm_sysctl.c   Sat Sep 29 14:19:43 2012 +0000
@@ -164,7 +164,55 @@
 
 #ifdef __NetBSD__
 #define SYSCTL_OUT(x, y, z) \
-       (len+=z,(len<*oldlenp)?(strcat((char*)oldp, y),0):EOVERFLOW)
+       drm_sysctl_out(oldp, oldlenp, &len, y, z, &error, &retcode);
+
+static int
+drm_sysctl_out(void *oldp, size_t *oldlenp, size_t *lenp,
+              const char *buf, size_t buflen,
+              int *errorp, int *retcodep)
+{
+       size_t copylen;
+       int error = 0;
+
+       /*
+        * If there's room left in the user buffer,
+        * copy out as much data as there is room for.
+        */
+
+       if (*lenp < *oldlenp) {
+               copylen = MIN(buflen, *oldlenp - *lenp);
+               error = copyout(buf, (char *)oldp + *lenp, copylen);
+               if (error) {
+                       *errorp = error;
+               }
+       } else {
+               copylen = 0;
+       }
+       *lenp += buflen;
+
+       /*
+        * If we didn't copy everything, remember that we should
+        * return ENOMEM at the end.
+        */
+
+       if (copylen < buflen && *errorp == 0) {
+               *errorp = ENOMEM;
+       }
+
+       /*
+        * If this is the final call (indicated by the buffer
+        * being the string terminator byte), return the
+        * total space required in *oldlenp and return
+        * the saved error in *retcodep.
+        */
+
+       if (buflen == 1 && *buf == 0) {
+               *oldlenp = *lenp;
+               *retcodep = *errorp;
+       }
+       return error;
+}
+
 #endif
 
 #define DRM_SYSCTL_PRINT(fmt, arg...)                          \
@@ -181,7 +229,8 @@
        struct drm_device *dev = arg1;
 #elif   defined(__NetBSD__)
        struct drm_device *dev = rnode->sysctl_data;
-       int len = 0;
+       size_t len = 0;
+       int error = 0;
 #endif
        char buf[128];
        int retcode;
@@ -219,7 +268,8 @@
        struct drm_device *dev = arg1;
 #elif   defined(__NetBSD__)
        struct drm_device *dev = rnode->sysctl_data;
-       int len = 0;
+       size_t len = 0;
+       int error = 0;
 #endif
        drm_local_map_t *map, *tempmaps;
        const char   *types[] = { "FB", "REG", "SHM", "AGP", "SG", "GEM", "TTM" };
@@ -284,7 +334,8 @@
        struct drm_device *dev = arg1;
 #elif   defined(__NetBSD__)
        struct drm_device *dev = rnode->sysctl_data;
-       int len = 0;
+       size_t len = 0;
+       int error = 0;
 #endif
        drm_device_dma_t *dma = dev->dma;
        drm_device_dma_t tempdma;
@@ -346,7 +397,8 @@
        struct drm_device *dev = arg1;
 #elif   defined(__NetBSD__)
        struct drm_device *dev = rnode->sysctl_data;
-       int len = 0;
+       size_t len = 0;
+       int error = 0;
 #endif
        struct drm_file *priv, *tempprivs;
        char buf[128];