From b1a0f704950296b2363192ba91999eef3635700f Mon Sep 17 00:00:00 2001 From: Eli Zaretskii Date: Sat, 21 Mar 2015 10:48:34 +0200 Subject: [PATCH] Fix undefined behavior in TUI's TAB expansion gdb/ChangeLog: * tui/tui-io.c (tui_expand_tabs): Reinitialize the column counter before the second loop, to avoid undefined behavior. Reported by Anton Blanchard . --- gdb/ChangeLog | 6 ++++++ gdb/tui/tui-io.c | 16 ++++++++-------- 2 files changed, 14 insertions(+), 8 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 969faace442..9b6deb446dd 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2015-03-21 Eli Zaretskii + + * tui/tui-io.c (tui_expand_tabs): Reinitialize the column counter + before the second loop, to avoid undefined behavior. Reported by + Anton Blanchard . + 2015-03-20 Keven Boell * gdbtypes.c (resolve_dynamic_type_internal): Adapt diff --git a/gdb/tui/tui-io.c b/gdb/tui/tui-io.c index c8b85672c0f..97906ceb45e 100644 --- a/gdb/tui/tui-io.c +++ b/gdb/tui/tui-io.c @@ -668,20 +668,20 @@ tui_getc (FILE *fp) char * tui_expand_tabs (const char *string, int col) { - int n_adjust; + int n_adjust, ncol; const char *s; char *ret, *q; /* 1. How many additional characters do we need? */ - for (n_adjust = 0, s = string; s; ) + for (ncol = col, n_adjust = 0, s = string; s; ) { s = strpbrk (s, "\t"); if (s) { - col += (s - string) + n_adjust; + ncol += (s - string) + n_adjust; /* Adjustment for the next tab stop, minus one for the TAB we replace with spaces. */ - n_adjust += 8 - (col % 8) - 1; + n_adjust += 8 - (ncol % 8) - 1; s++; } } @@ -690,7 +690,7 @@ tui_expand_tabs (const char *string, int col) ret = q = xmalloc (strlen (string) + n_adjust + 1); /* 2. Copy the original string while replacing TABs with spaces. */ - for (s = string; s; ) + for (ncol = col, s = string; s; ) { const char *s1 = strpbrk (s, "\t"); if (s1) @@ -699,12 +699,12 @@ tui_expand_tabs (const char *string, int col) { strncpy (q, s, s1 - s); q += s1 - s; - col += s1 - s; + ncol += s1 - s; } do { *q++ = ' '; - col++; - } while ((col % 8) != 0); + ncol++; + } while ((ncol % 8) != 0); s1++; } else -- 2.30.2