emacs/emacs-ctags-local-command-execute-vulnerability.patch
2023-01-18 10:14:29 +00:00

224 lines
6.9 KiB
Diff

diff --git a/lib-src/etags.c b/lib-src/etags.c
index 588921bc70..a156444281 100644
--- a/lib-src/etags.c
+++ b/lib-src/etags.c
@@ -371,7 +371,7 @@ static void just_read_file (FILE *);
static language *get_language_from_langname (const char *);
static void readline (linebuffer *, FILE *);
-static long readline_internal (linebuffer *, FILE *, char const *);
+static long readline_internal (linebuffer *, FILE *, char const *, const bool);
static bool nocase_tail (const char *);
static void get_tag (char *, char **);
static void get_lispy_tag (char *);
@@ -394,7 +394,9 @@ static void free_fdesc (fdesc *);
static void pfnote (char *, bool, char *, int, int, long);
static void invalidate_nodes (fdesc *, node **);
static void put_entries (node *);
+static void clean_matched_file_tag (char const * const, char const * const);
+static void do_move_file (const char *, const char *);
static char *concat (const char *, const char *, const char *);
static char *skip_spaces (char *);
static char *skip_non_spaces (char *);
@@ -1307,7 +1309,7 @@ main (int argc, char **argv)
if (parsing_stdin)
fatal ("cannot parse standard input "
"AND read file names from it");
- while (readline_internal (&filename_lb, stdin, "-") > 0)
+ while (readline_internal (&filename_lb, stdin, "-", false) > 0)
process_file_name (filename_lb.buffer, lang);
}
else
@@ -1355,9 +1357,6 @@ main (int argc, char **argv)
/* From here on, we are in (CTAGS && !cxref_style) */
if (update)
{
- char *cmd =
- xmalloc (strlen (tagfile) + whatlen_max +
- sizeof "mv..OTAGS;grep -Fv '\t\t' OTAGS >;rm OTAGS");
for (i = 0; i < current_arg; ++i)
{
switch (argbuffer[i].arg_type)
@@ -1368,17 +1367,8 @@ main (int argc, char **argv)
default:
continue; /* the for loop */
}
- char *z = stpcpy (cmd, "mv ");
- z = stpcpy (z, tagfile);
- z = stpcpy (z, " OTAGS;grep -Fv '\t");
- z = stpcpy (z, argbuffer[i].what);
- z = stpcpy (z, "\t' OTAGS >");
- z = stpcpy (z, tagfile);
- strcpy (z, ";rm OTAGS");
- if (system (cmd) != EXIT_SUCCESS)
- fatal ("failed to execute shell command");
+ clean_matched_file_tag (tagfile, argbuffer[i].what);
}
- free (cmd);
append_to_tagfile = true;
}
@@ -1407,6 +1397,51 @@ main (int argc, char **argv)
return EXIT_SUCCESS;
}
+/*
+ * Equivalent to: mv tags OTAGS;grep -Fv ' filename ' OTAGS >tags;rm OTAGS
+ */
+static void
+clean_matched_file_tag (const char* tagfile, const char* match_file_name)
+{
+ FILE *otags_f = fopen ("OTAGS", "wb");
+ FILE *tag_f = fopen (tagfile, "rb");
+
+ if (otags_f == NULL)
+ pfatal ("OTAGS");
+
+ if (tag_f == NULL)
+ pfatal (tagfile);
+
+ int buf_len = strlen (match_file_name) + sizeof ("\t\t ") + 1;
+ char *buf = xmalloc (buf_len);
+ snprintf (buf, buf_len, "\t%s\t", match_file_name);
+
+ linebuffer line;
+ linebuffer_init (&line);
+ while (readline_internal (&line, tag_f, tagfile, true) > 0)
+ {
+ if (ferror (tag_f))
+ pfatal (tagfile);
+
+ if (strstr (line.buffer, buf) == NULL)
+ {
+ fprintf (otags_f, "%s\n", line.buffer);
+ if (ferror (tag_f))
+ pfatal (tagfile);
+ }
+ }
+ free (buf);
+ free (line.buffer);
+
+ if (fclose (otags_f) == EOF)
+ pfatal ("OTAGS");
+
+ if (fclose (tag_f) == EOF)
+ pfatal (tagfile);
+
+ do_move_file ("OTAGS", tagfile);
+ return;
+}
/*
* Return a compressor given the file name. If EXTPTR is non-zero,
@@ -1794,7 +1829,7 @@ find_entries (FILE *inf)
/* Else look for sharp-bang as the first two characters. */
if (parser == NULL
- && readline_internal (&lb, inf, infilename) > 0
+ && readline_internal (&lb, inf, infilename, false) > 0
&& lb.len >= 2
&& lb.buffer[0] == '#'
&& lb.buffer[1] == '!')
@@ -6293,7 +6328,7 @@ analyze_regex (char *regex_arg)
if (regexfp == NULL)
pfatal (regexfile);
linebuffer_init (&regexbuf);
- while (readline_internal (&regexbuf, regexfp, regexfile) > 0)
+ while (readline_internal (&regexbuf, regexfp, regexfile, false) > 0)
analyze_regex (regexbuf.buffer);
free (regexbuf.buffer);
if (fclose (regexfp) != 0)
@@ -6648,11 +6683,13 @@ get_lispy_tag (register char *bp)
/*
* Read a line of text from `stream' into `lbp', excluding the
- * newline or CR-NL, if any. Return the number of characters read from
- * `stream', which is the length of the line including the newline.
+ * newline or CR-NL (if `leave_cr` is false), if any. Return the
+ * number of characters read from `stream', which is the length
+ * of the line including the newline.
*
- * On DOS or Windows we do not count the CR character, if any before the
- * NL, in the returned length; this mirrors the behavior of Emacs on those
+ * On DOS or Windows, if `leave_cr` is false, we do not count the
+ * CR character, if any before the NL, in the returned length;
+ * this mirrors the behavior of Emacs on those
* platforms (for text files, it translates CR-NL to NL as it reads in the
* file).
*
@@ -6660,7 +6697,7 @@ get_lispy_tag (register char *bp)
* appended to `filebuf'.
*/
static long
-readline_internal (linebuffer *lbp, FILE *stream, char const *filename)
+readline_internal (linebuffer *lbp, FILE *stream, char const *filename, const bool leave_cr)
{
char *buffer = lbp->buffer;
char *p = lbp->buffer;
@@ -6691,7 +6728,7 @@ readline_internal (linebuffer *lbp, FILE *stream, char const *filename)
}
if (c == '\n')
{
- if (p > buffer && p[-1] == '\r')
+ if (!leave_cr && p > buffer && p[-1] == '\r')
{
p -= 1;
chars_deleted = 2;
@@ -6736,7 +6773,7 @@ readline (linebuffer *lbp, FILE *stream)
long result;
linecharno = charno; /* update global char number of line start */
- result = readline_internal (lbp, stream, infilename); /* read line */
+ result = readline_internal (lbp, stream, infilename, false); /* read line */
lineno += 1; /* increment global line number */
charno += result; /* increment global char number */
@@ -7104,6 +7141,46 @@ etags_mktmp (void)
return templt;
}
+static void
+do_move_file(const char *src_file, const char *dst_file)
+{
+ if (rename (src_file, dst_file) == 0)
+ return;
+
+ FILE *src_f = fopen (src_file, "rb");
+ FILE *dst_f = fopen (dst_file, "wb");
+
+ if (src_f == NULL)
+ pfatal (src_file);
+
+ if (dst_f == NULL)
+ pfatal (dst_file);
+
+ int c;
+ while ((c = fgetc (src_f)) != EOF)
+ {
+ if (ferror (src_f))
+ pfatal (src_file);
+
+ if (ferror (dst_f))
+ pfatal (dst_file);
+
+ if (fputc (c, dst_f) == EOF)
+ pfatal ("cannot write");
+ }
+
+ if (fclose (src_f) == EOF)
+ pfatal (src_file);
+
+ if (fclose (dst_f) == EOF)
+ pfatal (dst_file);
+
+ if (unlink (src_file) == -1)
+ pfatal ("unlink error");
+
+ return;
+}
+
/* Return a newly allocated string containing the file name of FILE
relative to the absolute directory DIR (which should end with a slash). */
static char *