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| author | Eli Zaretskii <eliz@gnu.org> | 2016-10-23 16:54:00 +0300 |
|---|---|---|
| committer | Eli Zaretskii <eliz@gnu.org> | 2016-10-23 16:54:00 +0300 |
| commit | 9afea93ed536fb9110ac62b413604cf4c4302199 (patch) | |
| tree | 1730d866aa1b10e47e163596a97f69fba907c8f0 /src/xml.c | |
| parent | b8e8e1528829516ccce5ce0be8b97cdce0a86999 (diff) | |
| download | emacs-9afea93ed536fb9110ac62b413604cf4c4302199.tar.gz emacs-9afea93ed536fb9110ac62b413604cf4c4302199.tar.bz2 emacs-9afea93ed536fb9110ac62b413604cf4c4302199.zip | |
Attempt to catch reads from a buffer that is relocated
* src/xml.c (parse_region): Add assertion to ensure buffer text is
not relocated while libxml2 is reading it. (Bug#24764)
Diffstat (limited to 'src/xml.c')
| -rw-r--r-- | src/xml.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/src/xml.c b/src/xml.c index b1175d14a1a..1ef84bd917e 100644 --- a/src/xml.c +++ b/src/xml.c @@ -181,6 +181,7 @@ parse_region (Lisp_Object start, Lisp_Object end, Lisp_Object base_url, Lisp_Object result = Qnil; const char *burl = ""; ptrdiff_t istart, iend, istart_byte, iend_byte; + unsigned char *buftext; xmlCheckVersion (LIBXML_VERSION); @@ -200,18 +201,24 @@ parse_region (Lisp_Object start, Lisp_Object end, Lisp_Object base_url, burl = SSDATA (base_url); } + buftext = BYTE_POS_ADDR (istart_byte); if (htmlp) - doc = htmlReadMemory ((char *) BYTE_POS_ADDR (istart_byte), + doc = htmlReadMemory ((char *)buftext, iend_byte - istart_byte, burl, "utf-8", HTML_PARSE_RECOVER|HTML_PARSE_NONET| HTML_PARSE_NOWARNING|HTML_PARSE_NOERROR| HTML_PARSE_NOBLANKS); else - doc = xmlReadMemory ((char *) BYTE_POS_ADDR (istart_byte), + doc = xmlReadMemory ((char *)buftext, iend_byte - istart_byte, burl, "utf-8", XML_PARSE_NONET|XML_PARSE_NOWARNING| XML_PARSE_NOBLANKS |XML_PARSE_NOERROR); + /* If the assertion below fails, malloc was called inside the above + libxml2 functions, and ralloc.c caused relocation of buffer text, + so we could have read from unrelated memory. */ + eassert (buftext == BYTE_POS_ADDR (istart_byte)); + if (doc != NULL) { Lisp_Object r = Qnil; |