+++ /dev/null
-From: Goswin Brederlow <goswin.brederlow@student.uni-tuebingen.de>
-Subject: Bug#129345: patch to prevent a loop between libdl and libsafe causing libdl to crash
-To: 129345@bugs.debian.org
-Date: 01 Sep 2002 23:54:35 +0200
-Reply-To: Goswin Brederlow <goswin.brederlow@student.uni-tuebingen.de>,
- 129345@bugs.debian.org
-Resent-From: Goswin Brederlow <goswin.brederlow@student.uni-tuebingen.de>
-
-
--------
-[D. Coe edited this patch slightly -- moved an unrelated change into the
-Makefile itself [it changed the debugging comments only], and corrected a
-spelling error and reworded the comments. The original patch is in the
-bug tracking system, if you want to see it as submitted by Goswin.]
--------
--------
-D. Coe subsequently modified the patch further, because in some cases
-the initializations did not occur (e.g. when IO_vfscanf or memcpy was
-called from ps or top (likely one of the libraries they use). maybe
-they do something that disables libsafe's library globals initialization?
-
-
-In any case, I've adopted both strategise in this new patch; the addresses
-are preloaded as Goswin had coded, but they are also individually checked
-each time needed (as was the case before Goswin's patch), and are initialized
-at that point if necessary. Hopefully this will let ps and top work
-and also continue to work around the libdl problem.
--------
-
-Hi,
-
-if libsafe is invoked from inside libdl (or only inside dlerror()?)
-and a real_XXX function is not yet looked up it will reenter
-libdl. That causes memory corruption resulting in a read from 0x0 and
-thus segfault.
-
-The patch below makes libsafe cache all needed symbols once upon
-init. That not only causes less lookups than before but should prevent
-fatal loops. Failures of the initial lookups might not be reported
-correctly but terminate in some odd way if the functions needed to
-report are not yet looked up.
-
-MfG
- Goswin
-
-----------------------------------------------------------------------
-diff -Nurd libsafe-2.0-16/src/intercept.c libsafe-2.0-16-mrvn/src/intercept.c
---- libsafe-2.0-16/src/intercept.c 2002-05-31 19:37:34.000000000 +0200
-+++ libsafe-2.0-16-mrvn/src/intercept.c 2002-09-01 23:44:55.000000000 +0200
-@@ -128,14 +128,29 @@
- }
-
-
--/* Starting with version 2.0, we keep a single global copy of the pointer to
-- * the real memcpy() function. This allows us to call
-- * getLibraryFunction("memcpy") just once instead of multiple times, since
-- * memcpy() is needed in four different functions below.
-+/* Starting with Debian version 2.0-16-2, we keep a global copy of the pointer
-+ * to each real functions. Otherwise a getLibraryFunction might
-+ * be triggered from inside dlsym() and cause memory corruption reulting in a
-+ * segfault.
- */
--static memcpy_t real_memcpy = NULL;
--
--
-+static memcpy_t real_memcpy = NULL;
-+static _IO_vfscanf_t real_IO_vfscanf = NULL;
-+static vfprintf_t real_vfprintf = NULL;
-+static vsnprintf_t real_vsnprintf = NULL;
-+static vsprintf_t real_vsprintf = NULL;
-+static gets_t real_gets = NULL;
-+static getwd_t real_getwd = NULL;
-+static realpath_t real_realpath = NULL;
-+static stpcpy_t real_stpcpy = NULL;
-+static strcat_t real_strcat = NULL;
-+static strcpy_t real_strcpy = NULL;
-+static strncat_t real_strncat = NULL;
-+static strncpy_t real_strncpy = NULL;
-+static wcscpy_t real_wcscpy = NULL;
-+static wcpcpy_t real_wcpcpy = NULL;
-+#ifndef MISSING_WCSNLEN
-+static wcscat_t real_wcscat = NULL;
-+#endif
- /*
- * -------------- system library implementations -------------------
- * Here is the story: if a C source file includes <string.h> and is
-@@ -150,7 +165,6 @@
- */
- char *strcpy(char *dest, const char *src)
- {
-- static strcpy_t real_strcpy = NULL;
- size_t max_size, len;
-
- if (!real_memcpy)
-@@ -182,7 +196,6 @@
-
- char *strncpy(char *dest, const char *src, size_t n)
- {
-- static strncpy_t real_strncpy = NULL;
- size_t max_size, len;
-
- if (!real_strncpy)
-@@ -206,7 +219,6 @@
-
- char *stpcpy(char *dest, const char *src)
- {
-- static stpcpy_t real_stpcpy = NULL;
- size_t max_size, len;
-
- if (!real_memcpy)
-@@ -239,7 +251,6 @@
- #ifndef MISSING_WCSNLEN
- wchar_t *wcscpy(wchar_t *dest, const wchar_t *src)
- {
-- static wcscpy_t real_wcscpy = NULL;
- size_t max_bytes, max_wchars, len;
-
- if (!real_wcscpy)
-@@ -280,7 +291,6 @@
-
- wchar_t *wcpcpy(wchar_t *dest, const wchar_t *src)
- {
-- static wcpcpy_t real_wcpcpy = NULL;
- size_t max_bytes, max_wchars, len;
-
- if (!real_wcpcpy)
-@@ -347,7 +357,6 @@
-
- char *strcat(char *dest, const char *src)
- {
-- static strcat_t real_strcat = NULL;
- size_t max_size;
- uint dest_len, src_len;
-
-@@ -379,7 +388,6 @@
-
- char *strncat(char *dest, const char *src, size_t n)
- {
-- static strncat_t real_strncat = NULL;
- size_t max_size;
- uint dest_len, src_len;
-
-@@ -408,7 +416,6 @@
- #ifndef MISSING_WCSNLEN
- wchar_t *wcscat(wchar_t *dest, const wchar_t *src)
- {
-- static wcscat_t real_wcscat = NULL;
- size_t max_bytes;
- uint dest_len, src_len;
-
-@@ -861,7 +868,6 @@
- */
- int vfprintf(FILE *fp, const char *format, va_list ap)
- {
-- static vfprintf_t real_vfprintf = NULL;
- int res;
- char *p, *pnum;
- int c = -1; /* Next var arg to be used */
-@@ -1026,7 +1032,6 @@
- */
- int _IO_vfprintf(FILE *fp, const char *format, va_list ap)
- {
-- static vfprintf_t real_vfprintf = NULL;
- int res;
- char *p, *pnum;
- int c = -1; /* Next var arg to be used */
-@@ -1189,8 +1194,6 @@
-
- int sprintf(char *str, const char *format, ...)
- {
-- static vsprintf_t real_vsprintf = NULL;
-- static vsnprintf_t real_vsnprintf = NULL;
- size_t max_size;
- va_list ap;
- int res;
-@@ -1239,7 +1242,6 @@
-
- int snprintf(char *str, size_t size, const char *format, ...)
- {
-- static vsnprintf_t real_vsnprintf = NULL;
- size_t max_size;
- va_list ap;
- int res;
-@@ -1286,8 +1288,6 @@
-
- int vsprintf(char *str, const char *format, va_list ap)
- {
-- static vsprintf_t real_vsprintf = NULL;
-- static vsnprintf_t real_vsnprintf = NULL;
- size_t max_size;
- int res;
-
-@@ -1325,7 +1325,6 @@
-
- int vsnprintf(char *str, size_t size, const char *format, va_list ap)
- {
-- static vsnprintf_t real_vsnprintf = NULL;
- size_t max_size;
- int res;
-
-@@ -1361,7 +1360,6 @@
-
- char *getwd(char *buf)
- {
-- static getwd_t real_getwd = NULL;
- size_t max_size;
- char *res;
-
-@@ -1386,7 +1384,6 @@
-
- char *gets(char *s)
- {
-- static gets_t real_gets = NULL;
- size_t max_size, len;
-
- if (!real_gets)
-@@ -1412,7 +1409,6 @@
-
- char *realpath(char *path, char resolved_path[])
- {
-- static realpath_t real_realpath = NULL;
- size_t max_size, len;
- char *res;
- char buf[MAXPATHLEN + 1];
-@@ -1445,7 +1441,6 @@
-
- int _IO_vfscanf (_IO_FILE *s, const char *format, _IO_va_list argptr, int *errp)
- {
-- static _IO_vfscanf_t real_IO_vfscanf = NULL;
- int res, save_count;
- caddr_t ra_array[MAXLEVELS], fp_array[MAXLEVELS];
-
-@@ -1529,6 +1524,25 @@
-
- fclose(fp);
- }
-+
-+ real_memcpy = (memcpy_t) getLibraryFunction("memcpy");
-+ real_IO_vfscanf = (_IO_vfscanf_t) getLibraryFunction("_IO_vfscanf");
-+ real_vfprintf = (vfprintf_t) getLibraryFunction("vfprintf");
-+ real_vsnprintf = (vsnprintf_t) getLibraryFunction("vsnprintf");
-+ real_vsprintf = (vsprintf_t) getLibraryFunction("vsprintf");
-+ real_gets = (gets_t) getLibraryFunction("gets");
-+ real_getwd = (getwd_t) getLibraryFunction("getwd");
-+ real_realpath = (realpath_t) getLibraryFunction("realpath");
-+ real_stpcpy = (stpcpy_t) getLibraryFunction("stpcpy");
-+ real_strcat = (strcat_t) getLibraryFunction("strcat");
-+ real_strcpy = (strcpy_t) getLibraryFunction("strcpy");
-+ real_strncat = (strncat_t) getLibraryFunction("strncat");
-+ real_strncpy = (strncpy_t) getLibraryFunction("strncpy");
-+ real_wcscpy = (wcscpy_t) getLibraryFunction("wcscpy");
-+ real_wcpcpy = (wcpcpy_t) getLibraryFunction("wcpcpy");
-+#ifndef MISSING_WCSNLEN
-+ real_wcscat = (wcscat_t) getLibraryFunction("wcscat");
-+#endif
- }
-
-
projects / people / teissler / ipfire-2.x.git / blobdiff