view src/beval.c @ 33815:08f9e1eac4cf v9.0.2123

patch 9.0.2123: Problem with initializing the length of range() lists Commit: https://github.com/vim/vim/commit/df63da98d8dc284b1c76cfe1b17fa0acbd6094d8 Author: Christian Brabandt <cb@256bit.org> Date: Thu Nov 23 20:14:28 2023 +0100 patch 9.0.2123: Problem with initializing the length of range() lists Problem: Problem with initializing the length of range() lists Solution: Set length explicitly when it shouldn't contain any items range() may cause a wrong calculation of list length, which may later then cause a segfault in list_find(). This is usually not a problem, because range_list_materialize() calculates the length, when it materializes the list. In addition, in list_find() when the length of the range was wrongly initialized, it may seem to be valid, so the check for list index out-of-bounds will not be true, because it is called before the list is actually materialized. And so we may eventually try to access a null pointer, causing a segfault. So this patch does 3 things: - In f_range(), when we know that the list should be empty, explicitly set the list->lv_len value to zero. This should happen, when start is larger than end (in case the stride is positive) or end is larger than start when the stride is negative. This should fix the underlying issue properly. However, - as a safety measure, let's check that the requested index is not out of range one more time, after the list has been materialized and return NULL in case it suddenly is. - add a few more tests to verify the behaviour. fixes: #13557 closes: #13563 Co-authored-by: Tim Pope <tpope@github.com> Signed-off-by: Christian Brabandt <cb@256bit.org>
author Christian Brabandt <cb@256bit.org>
date Thu, 23 Nov 2023 20:30:07 +0100
parents 8fc442c731ca
children
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *			Visual Workshop integration by Gordon Prieur
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

#include "vim.h"

#if defined(FEAT_BEVAL) || defined(FEAT_PROP_POPUP) || defined(PROTO)
/*
 * Find text under the mouse position "row" / "col".
 * If "getword" is TRUE the returned text in "*textp" is not the whole line but
 * the relevant word in allocated memory.
 * Return OK if found.
 * Return FAIL if not found, no text at the mouse position.
 */
    int
find_word_under_cursor(
	int	    mouserow,
	int	    mousecol,
	int	    getword,
	int	    flags,	// flags for find_ident_at_pos()
	win_T	    **winp,	// can be NULL
	linenr_T    *lnump,	// can be NULL
	char_u	    **textp,
	int	    *colp,	// column where mouse hovers, can be NULL
	int	    *startcolp) // column where text starts, can be NULL
{
    int		row = mouserow;
    int		col = mousecol;
    int		scol;
    win_T	*wp;
    char_u	*lbuf;
    linenr_T	lnum;

    *textp = NULL;
    wp = mouse_find_win(&row, &col, FAIL_POPUP);
    if (wp == NULL || row < 0 || row >= wp->w_height || col >= wp->w_width)
	return FAIL;

    // Found a window and the cursor is in the text.  Now find the line
    // number.
    if (mouse_comp_pos(wp, &row, &col, &lnum, NULL))
	return FAIL;		// position is below the last line

    // Not past end of the file.
    lbuf = ml_get_buf(wp->w_buffer, lnum, FALSE);
    if (col > win_linetabsize(wp, lnum, lbuf, (colnr_T)MAXCOL))
	return FAIL;		// past end of line

    // Not past end of line.
    if (getword)
    {
	// For Netbeans we get the relevant part of the line
	// instead of the whole line.
	int		len;
	pos_T	*spos = NULL, *epos = NULL;

	if (VIsual_active)
	{
	    if (LT_POS(VIsual, curwin->w_cursor))
	    {
		spos = &VIsual;
		epos = &curwin->w_cursor;
	    }
	    else
	    {
		spos = &curwin->w_cursor;
		epos = &VIsual;
	    }
	}

	col = vcol2col(wp, lnum, col, NULL);
	scol = col;

	if (VIsual_active
		&& wp->w_buffer == curwin->w_buffer
		&& (lnum == spos->lnum
		    ? col >= (int)spos->col
		    : lnum > spos->lnum)
		&& (lnum == epos->lnum
		    ? col <= (int)epos->col
		    : lnum < epos->lnum))
	{
	    // Visual mode and pointing to the line with the
	    // Visual selection: return selected text, with a
	    // maximum of one line.
	    if (spos->lnum != epos->lnum || spos->col == epos->col)
		return FAIL;

	    lbuf = ml_get_buf(curwin->w_buffer, VIsual.lnum, FALSE);
	    len = epos->col - spos->col;
	    if (*p_sel != 'e')
		len += mb_ptr2len(lbuf + epos->col);
	    lbuf = vim_strnsave(lbuf + spos->col, len);
	    lnum = spos->lnum;
	    col = spos->col;
	    scol = col;
	}
	else
	{
	    // Find the word under the cursor.
	    ++emsg_off;
	    len = find_ident_at_pos(wp, lnum, (colnr_T)col,
		    &lbuf, &scol, flags);
	    --emsg_off;
	    if (len == 0)
		return FAIL;
	    lbuf = vim_strnsave(lbuf, len);
	}
    }
    else
	scol = col;

    if (winp != NULL)
	*winp = wp;
    if (lnump != NULL)
	*lnump = lnum;
    *textp = lbuf;
    if (colp != NULL)
	*colp = col;
    if (startcolp != NULL)
	*startcolp = scol;

    return OK;
}
#endif

#if defined(FEAT_BEVAL) || defined(PROTO)

/*
 * Get the text and position to be evaluated for "beval".
 * If "getword" is TRUE the returned text is not the whole line but the
 * relevant word in allocated memory.
 * Returns OK or FAIL.
 */
    int
get_beval_info(
	BalloonEval	*beval,
	int		getword,
	win_T		**winp,
	linenr_T	*lnump,
	char_u		**textp,
	int		*colp)
{
    int		row = mouse_row;
    int		col = mouse_col;

# ifdef FEAT_BEVAL_GUI
    if (gui.in_use)
    {
	row = Y_2_ROW(beval->y);
	col = X_2_COL(beval->x);
    }
# endif
    if (find_word_under_cursor(row, col, getword,
		FIND_IDENT + FIND_STRING + FIND_EVAL,
		winp, lnump, textp, colp, NULL) == OK)
    {
# ifdef FEAT_VARTABS
	vim_free(beval->vts);
	beval->vts = tabstop_copy((*winp)->w_buffer->b_p_vts_array);
	if ((*winp)->w_buffer->b_p_vts_array != NULL && beval->vts == NULL)
	{
	    if (getword)
		vim_free(*textp);
	    return FAIL;
	}
# endif
	beval->ts = (*winp)->w_buffer->b_p_ts;
	return OK;
    }

    return FAIL;
}

/*
 * Show a balloon with "mesg" or "list".
 * Hide the balloon when both are NULL.
 */
    void
post_balloon(BalloonEval *beval UNUSED, char_u *mesg, list_T *list UNUSED)
{
# ifdef FEAT_BEVAL_TERM
#  ifdef FEAT_GUI
    if (!gui.in_use)
#  endif
	ui_post_balloon(mesg, list);
# endif
# ifdef FEAT_BEVAL_GUI
    if (gui.in_use)
	// GUI can't handle a list
	gui_mch_post_balloon(beval, mesg);
# endif
}

/*
 * Returns TRUE if the balloon eval has been enabled:
 * 'ballooneval' for the GUI and 'balloonevalterm' for the terminal.
 * Also checks if the screen isn't scrolled up.
 */
    int
can_use_beval(void)
{
    return (0
#ifdef FEAT_BEVAL_GUI
		|| (gui.in_use && p_beval)
#endif
#ifdef FEAT_BEVAL_TERM
		|| (
# ifdef FEAT_GUI
		    !gui.in_use &&
# endif
		    p_bevalterm)
#endif
	     ) && msg_scrolled == 0;
}

# ifdef FEAT_EVAL
/*
 * Evaluate the expression 'bexpr' and set the text in the balloon 'beval'.
 */
    static void
bexpr_eval(
	BalloonEval	*beval,
	char_u		*bexpr,
	win_T		*wp,
	linenr_T	lnum,
	int		col,
	char_u		*text)
{
    win_T	*cw;
    long	winnr = 0;
    buf_T	*save_curbuf;
    int		use_sandbox;
    static char_u  *result = NULL;
    size_t	len;

    sctx_T	save_sctx = current_sctx;

    // Convert window pointer to number.
    for (cw = firstwin; cw != wp; cw = cw->w_next)
	++winnr;

    set_vim_var_nr(VV_BEVAL_BUFNR, (long)wp->w_buffer->b_fnum);
    set_vim_var_nr(VV_BEVAL_WINNR, winnr);
    set_vim_var_nr(VV_BEVAL_WINID, wp->w_id);
    set_vim_var_nr(VV_BEVAL_LNUM, (long)lnum);
    set_vim_var_nr(VV_BEVAL_COL, (long)(col + 1));
    set_vim_var_string(VV_BEVAL_TEXT, text, -1);
    vim_free(text);

    /*
     * Temporarily change the curbuf, so that we can determine whether
     * the buffer-local balloonexpr option was set insecurely.
     */
    save_curbuf = curbuf;
    curbuf = wp->w_buffer;
    use_sandbox = was_set_insecurely((char_u *)"balloonexpr",
				    *curbuf->b_p_bexpr == NUL ? 0 : OPT_LOCAL);
    curbuf = save_curbuf;
    if (use_sandbox)
	++sandbox;
    ++textlock;

    if (bexpr == p_bexpr)
    {
	sctx_T *sp = get_option_sctx("balloonexpr");

	if (sp != NULL)
	    current_sctx = *sp;
    }
    else
	current_sctx = curbuf->b_p_script_ctx[BV_BEXPR];

    vim_free(result);
    result = eval_to_string(bexpr, TRUE, TRUE);

    // Remove one trailing newline, it is added when the result was a
    // list and it's hardly ever useful.  If the user really wants a
    // trailing newline he can add two and one remains.
    if (result != NULL)
    {
	len = STRLEN(result);
	if (len > 0 && result[len - 1] == NL)
	    result[len - 1] = NUL;
    }

    if (use_sandbox)
	--sandbox;
    --textlock;
    current_sctx = save_sctx;

    set_vim_var_string(VV_BEVAL_TEXT, NULL, -1);
    if (result != NULL && result[0] != NUL)
	post_balloon(beval, result, NULL);

    // The 'balloonexpr' evaluation may show something on the screen
    // that requires a screen update.
    if (must_redraw)
	redraw_after_callback(FALSE, FALSE);
}
# endif

/*
 * Common code, invoked when the mouse is resting for a moment.
 */
    void
general_beval_cb(BalloonEval *beval, int state UNUSED)
{
#ifdef FEAT_EVAL
    win_T	*wp;
    int		col;
    linenr_T	lnum;
    char_u	*text;
    char_u	*bexpr;
#endif
    static int	recursive = FALSE;

    // Don't do anything when 'ballooneval' is off, messages scrolled the
    // windows up or we have no beval area.
    if (!can_use_beval() || beval == NULL)
	return;

    // Don't do this recursively.  Happens when the expression evaluation
    // takes a long time and invokes something that checks for CTRL-C typed.
    if (recursive)
	return;
    recursive = TRUE;

#ifdef FEAT_EVAL
    if (get_beval_info(beval, TRUE, &wp, &lnum, &text, &col) == OK)
    {
	bexpr = (*wp->w_buffer->b_p_bexpr == NUL) ? p_bexpr
						    : wp->w_buffer->b_p_bexpr;
	if (*bexpr != NUL)
	{
	    bexpr_eval(beval, bexpr, wp, lnum, col, text);
	    recursive = FALSE;
	    return;
	}
    }
#endif
#ifdef FEAT_NETBEANS_INTG
    if (bevalServers & BEVAL_NETBEANS)
	netbeans_beval_cb(beval, state);
#endif

    recursive = FALSE;
}

#endif