[wiki] [sites] [dwm][patch][winicon] Prevent potential pointer overflow || AdamYuan

[git]

commit 66ce520d4a5ac684fda9b3e40dd8236d54e804db
Author: AdamYuan <y13916619...@126.com>
Date:   Fri Jul 23 13:42:32 2021 +0800

    [dwm][patch][winicon] Prevent potential pointer overflow

diff --git a/dwm.suckless.org/patches/winicon/dwm-winicon-6.2-v1.3.diff 
b/dwm.suckless.org/patches/winicon/dwm-winicon-6.2-v1.3.diff
index 34373a07..27d5ce22 100644
--- a/dwm.suckless.org/patches/winicon/dwm-winicon-6.2-v1.3.diff
+++ b/dwm.suckless.org/patches/winicon/dwm-winicon-6.2-v1.3.diff
@@ -81,7 +81,7 @@ index 4bcd5ad..07b6433 100644
  /* Map functions */
  void drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int 
h);
 diff --git a/dwm.c b/dwm.c
-index 4465af1..850dbbf 100644
+index 4465af1..b02a80c 100644
 --- a/dwm.c
 +++ b/dwm.c
 @@ -28,6 +28,8 @@
@@ -183,16 +183,16 @@ index 4465af1..850dbbf 100644
 +              const unsigned long *end = p + n;
 +              unsigned long *i;
 +              uint32_t bstd = UINT32_MAX, d, m;
-+              for (i = p; i + 1 < end; ) {
++              for (i = p; i < end - 1; i += sz) {
 +                      if ((w = *i++) > UINT16_MAX || (h = *i++) > UINT16_MAX) 
{ XFree(p); return NULL; }
-+                      m = w > h ? w : h; sz = w * h;
-+                      if ((i += sz) <= end && m >= ICONSIZE && (d = m - 
ICONSIZE) < bstd) { bstd = d; bstp = i - sz; }
++                      if ((sz = w * h) > end - i) break;
++                      if ((m = w > h ? w : h) >= ICONSIZE && (d = m - 
ICONSIZE) < bstd) { bstd = d; bstp = i; }
 +              }
 +              if (!bstp) {
-+                      for (i = p; i + 1 < end; ) {
++                      for (i = p; i < end - 1; i += sz) {
 +                              if ((w = *i++) > UINT16_MAX || (h = *i++) > 
UINT16_MAX) { XFree(p); return NULL; }
-+                              m = w > h ? w : h; sz = w * h;
-+                              if ((i += sz) <= end && (d = ICONSIZE - m) < 
bstd) { bstd = d; bstp = i - sz; }
++                              if ((sz = w * h) > end - i) break;
++                              if ((d = ICONSIZE - (w > h ? w : h)) < bstd) { 
bstd = d; bstp = i; }
 +                      }
 +              }
 +              if (!bstp) { XFree(p); return NULL; }