File u_libxfont_bdfreadcharacters_ensure_metrics_fit... of Package xorg-x11-libs

Overview Repositories Revisions Requests Users Attributes Meta

File u_libxfont_bdfreadcharacters_ensure_metrics_fit_into_xcharinfo_struct.patch of Package xorg-x11-libs

Subject: bdfReadCharacters: ensure metrics fit into xCharInfo struct
References: bnc#921978, CVE-2015-1804
Signed-off-by: msrb@suse.com

xCharInfo struct [CVE-2015-CCCC]
    being < 0 reduces the number of cases we need to check for overflow.
---
 src/bitmap/bdfread.c |   26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)
--- a/src/bitmap/bdfread.c	
+++ a/src/bitmap/bdfread.c	
@@ -62,8 +62,16 @@ from The Open Group.
 
 #if HAVE_STDINT_H
 #include <stdint.h>
-#elif !defined(INT32_MAX)
-#define INT32_MAX 0x7fffffff
+#else
+# ifndef INT32_MAX
+#  define INT32_MAX 0x7fffffff
+# endif
+# ifndef INT16_MAX
+#  define INT16_MAX 0x7fff
+# endif
+# ifndef INT16_MIN
+#  define INT16_MIN (0 - 0x8000)
+# endif
 #endif
 
 #define INDICES 256
@@ -417,6 +425,12 @@ bdfReadCharacters(FontFilePtr file, FontPtr pFont, bdfFileState *pState,
 	    bdfError("DWIDTH y value must be zero\n");
 	    goto BAILOUT;
 	}
+	/* xCharInfo metrics are stored as INT16 */
+	if ((wx < 0) || (wx > INT16_MAX)) {
+	    bdfError("character '%s' has out of range width, %d\n",
+		     charName, wx);
+	    goto BAILOUT;
+	}
 	line = bdfGetLine(file, lineBuf, BDFLINELEN);
 	if ((!line) || (sscanf((char *) line, "BBX %d %d %d %d", &bw, &bh, &bl, &bb) != 4)) {
 	    bdfError("bad 'BBX'\n");
@@ -427,6 +441,14 @@ bdfReadCharacters(FontFilePtr file, FontPtr pFont, bdfFileState *pState,
 		     charName, bw, bh);
 	    goto BAILOUT;
 	}
+	/* xCharInfo metrics are read as int, but stored as INT16 */
+	if ((bl > INT16_MAX) || (bl < INT16_MIN) ||
+	    (bb > INT16_MAX) || (bb < INT16_MIN) ||
+	    (bw > (INT16_MAX - bl)) || (bh > (INT16_MAX - bb))) {
+	    bdfError("character '%s' has out of range metrics, %d %d %d %d\n",
+		     charName, bl, (bl+bw), (bh+bb), -bb);
+	    goto BAILOUT;
+	}
 	line = bdfGetLine(file, lineBuf, BDFLINELEN);
 	if ((line) && (bdfIsPrefix(line, "ATTRIBUTES"))) {
 	    for (p = line + strlen("ATTRIBUTES ");
--

Places

File u_libxfont_bdfreadcharacters_ensure_metrics_fit_into_xcharinfo_struct.patch of Package xorg-x11-libs

Places