[PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Josiah Worcester]

---
 src/compat/asprintf_chk.c  |  18 +++++++
 src/compat/chk_fail.c      |   7 +++
 src/compat/confstr_chk.c   |   8 +++
 src/compat/dprintf_chk.c   |  17 ++++++
 src/compat/gnu_chk.c       |  18 +++++++
 src/compat/longjmp_chk.c   |   7 +++
 src/compat/posix_chk.c     | 132 +++++++++++++++++++++++++++++++++++++++++++++
 src/compat/printf_chk.c    |  70 ++++++++++++++++++++++++
 src/compat/realpath_chk.c  |   9 ++++
 src/compat/stdio_chk.c     |  50 +++++++++++++++++
 src/compat/string_chk.c    |  98 +++++++++++++++++++++++++++++++++
 src/compat/syslog_chk.c    |  17 ++++++
 src/compat/ttyname_r_chk.c |   7 +++
 src/compat/wchar_chk.c     |  45 ++++++++++++++++
 src/compat/wprintf_chk.c   |  51 ++++++++++++++++++
 15 files changed, 554 insertions(+)
 create mode 100644 src/compat/asprintf_chk.c
 create mode 100644 src/compat/chk_fail.c
 create mode 100644 src/compat/confstr_chk.c
 create mode 100644 src/compat/dprintf_chk.c
 create mode 100644 src/compat/gnu_chk.c
 create mode 100644 src/compat/longjmp_chk.c
 create mode 100644 src/compat/posix_chk.c
 create mode 100644 src/compat/printf_chk.c
 create mode 100644 src/compat/realpath_chk.c
 create mode 100644 src/compat/stdio_chk.c
 create mode 100644 src/compat/string_chk.c
 create mode 100644 src/compat/syslog_chk.c
 create mode 100644 src/compat/ttyname_r_chk.c
 create mode 100644 src/compat/wchar_chk.c
 create mode 100644 src/compat/wprintf_chk.c

diff --git a/src/compat/asprintf_chk.c b/src/compat/asprintf_chk.c
new file mode 100644
index 0000000..56e2935
--- /dev/null
+++ b/src/compat/asprintf_chk.c
@@ -0,0 +1,18 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdarg.h>
+
+int __asprintf_chk(char **restrict s, int flag, const char *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vasprintf(s, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __vasprintf_chk(char **restrict s, int flag, const char *restrict fmt, va_list ap)
+{
+	return vasprintf(s, fmt, ap);
+}
diff --git a/src/compat/chk_fail.c b/src/compat/chk_fail.c
new file mode 100644
index 0000000..ef069c5
--- /dev/null
+++ b/src/compat/chk_fail.c
@@ -0,0 +1,7 @@
+#include "atomic.h"
+
+void __chk_fail(void)
+{
+	a_crash();
+	for(;;);
+}
diff --git a/src/compat/confstr_chk.c b/src/compat/confstr_chk.c
new file mode 100644
index 0000000..61bcd42
--- /dev/null
+++ b/src/compat/confstr_chk.c
@@ -0,0 +1,8 @@
+#include <unistd.h>
+#include <atomic.h>
+
+size_t __confstr_chk(int name, char *buf, size_t len, size_t buflen)
+{
+	if (buflen < len) a_crash();
+	return confstr(name, buf, len);
+}
diff --git a/src/compat/dprintf_chk.c b/src/compat/dprintf_chk.c
new file mode 100644
index 0000000..e09469d
--- /dev/null
+++ b/src/compat/dprintf_chk.c
@@ -0,0 +1,17 @@
+#include <stdio.h>
+#include <stdarg.h>
+
+int __dprintf_chk(int fd, int flag, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vdprintf(fd, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __vdprintf(int fd, int flag, const char *fmt, va_list ap)
+{
+	return vdprintf(fd, fmt, ap);
+}
diff --git a/src/compat/gnu_chk.c b/src/compat/gnu_chk.c
new file mode 100644
index 0000000..bc2f2d8
--- /dev/null
+++ b/src/compat/gnu_chk.c
@@ -0,0 +1,18 @@
+#define _GNU_SOURCE
+#include <string.h>
+#include <poll.h>
+#include <stddef.h>
+#include "atomic.h"
+#include "atomic.h"
+
+int __ppoll_chk(struct pollfd *fds, nfds_t n, const struct timespec *to, const sigset_t *mask, size_t fdslen)
+{
+	if (fdslen / sizeof(*fds) < n) a_crash();
+	return ppoll(fds, n, to, mask);
+}
+
+void *__mempcpy_chk(void *dest, const void *src, size_t n, size_t destlen)
+{
+	if (destlen < n) a_crash();
+	return mempcpy(dest, src, n);
+}
diff --git a/src/compat/longjmp_chk.c b/src/compat/longjmp_chk.c
new file mode 100644
index 0000000..e814ecc
--- /dev/null
+++ b/src/compat/longjmp_chk.c
@@ -0,0 +1,7 @@
+#include <setjmp.h>
+#include <signal.h>
+
+_Noreturn void __longjmp_chk(sigjmp_buf buf, int ret)
+{
+	longjmp((jmp_buf)buf, ret);
+}
diff --git a/src/compat/posix_chk.c b/src/compat/posix_chk.c
new file mode 100644
index 0000000..7e39754
--- /dev/null
+++ b/src/compat/posix_chk.c
@@ -0,0 +1,132 @@
+#include <poll.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <wchar.h>
+#include "atomic.h"
+
+ssize_t __read_chk(int fd, void *buf, size_t count, size_t buflen)
+{
+	if (count > buflen) a_crash();
+	return read(fd, buf, count);
+}
+
+ssize_t __readlink_chk(const char *path, void *buf, size_t bufsize, size_t buflen)
+{
+	if (bufsize > buflen) a_crash();
+	return readlink(path, buf, bufsize);
+}
+
+ssize_t __readlinkat_chk(int fd, const char *path, void *buf, size_t bufsize, size_t buflen)
+{
+	if (bufsize > buflen) a_crash();
+	return readlinkat(fd, path, buf, bufsize);
+}
+
+ssize_t __recv_chk(int fd, void *buf, size_t len, size_t buflen, int flags)
+{
+	if (len > buflen) a_crash();
+	return recv(fd, buf, len, flags);
+}
+
+ssize_t __recvfrom_chk(int fd, void *buf, size_t len, size_t buflen, int flags, struct sockaddr *addr, socklen_t *alen)
+{
+	if (len > buflen) a_crash();
+	return recvfrom(fd, buf, len, flags, addr, alen);
+}
+
+int __open_2(const char *path, int flag)
+{
+	if (flag & O_CREAT) a_crash();
+	return open(path, flag);
+}
+
+int __open64_2(const char *path, int flag)
+{
+	return __open_2(path, flag);
+}
+
+int __openat_2(int fd, const char *path, int flag)
+{
+	if (flag & O_CREAT) a_crash();
+	return openat(fd, path, flag);
+}
+
+int __openat64_2(int fd, const char *path, int flag)
+{
+	return __openat_2(fd, path, flag);
+}
+
+int __poll_chk(struct pollfd *fds, nfds_t n, int timeout,  size_t fdslen)
+{
+	if (fdslen / sizeof(fds[0]) < n) a_crash();
+	return poll(fds, n, timeout);
+}
+
+ssize_t __pread_chk(int fd, void *buf, size_t size, size_t ofs, size_t buflen)
+{
+	if (size > buflen) a_crash();
+	return pread(fd, buf, size, ofs);
+}
+
+ssize_t __pread64_chk(int fd, void *buf, size_t size, size_t ofs, size_t buflen)
+{
+	return __pread_chk(fd, buf, size, ofs, buflen);
+}
+
+char *__getcwd_chk(char *buf, size_t len, size_t buflen)
+{
+	if (len > buflen) a_crash();
+	return getcwd(buf, len);
+}
+
+int __gethostname_chk(char *name, size_t len, size_t namelen)
+{
+	if (len > namelen) a_crash();
+	return gethostname(name, len);
+}
+
+long __fdelt_chk(long d)
+{
+	if (d < 0 || d >= FD_SETSIZE) a_crash();
+	return d / (8 * sizeof(d));
+}
+
+int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
+{
+	if (size > namelen) a_crash();
+	return ttyname_r(fd, name, size);
+}
+
+char *__stpcpy_chk(char *d, const char *s, size_t dlen)
+{
+	size_t slen = strnlen(s, dlen) + 1;
+	if (slen > dlen) a_crash();
+	return stpcpy(d, s);
+}
+
+char *__stpncpy_chk(char *d, const char *s, size_t n, size_t dlen)
+{
+	if (n > dlen) a_crash();
+	return stpncpy(d, s, n);
+}
+
+wchar_t *__wcpcpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t dlen)
+{
+	size_t slen = strnlen(s, dlen) + 1;
+	if (slen > dlen) a_crash();
+	return wcpcpy(d, s);
+}
+
+wchar_t *__wcpncpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t n, size_t dlen)
+{
+	if (n > dlen) a_crash();
+	return wcpncpy(d, s, n);
+}
+
+int __getgroups_chk(int count, gid_t list[], size_t len)
+{
+	if (count > len / sizeof(list[0])) a_crash();
+	return getgroups(count, list);
+}
diff --git a/src/compat/printf_chk.c b/src/compat/printf_chk.c
new file mode 100644
index 0000000..d74af61
--- /dev/null
+++ b/src/compat/printf_chk.c
@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <stdarg.h>
+#include "atomic.h"
+
+int __fprintf_chk(FILE *f, int flag, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vfprintf(f, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __printf_chk(int flag, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vfprintf(stdout, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __snprintf_chk(char *s, size_t n, int flag, size_t slen, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+	if (n > slen) a_crash();
+	ret = vsnprintf(s, slen, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __sprintf_chk(char *s, int flag, size_t slen, const char *fmt, ...)
+{
+	int ret;
+	va_list ap;
+	if (slen == 0) a_crash();
+	va_start(ap, fmt);
+	ret = vsnprintf(s, slen, fmt, ap);
+	va_end(ap);
+	if (ret > slen) a_crash();
+	return ret;
+}
+
+int __vfprintf_chk(FILE *f, int flag, const char *fmt, va_list ap)
+{
+	return vfprintf(f, fmt, ap);
+}
+
+int __vprintf_chk(int flag, const char *fmt, va_list ap)
+{
+	return vfprintf(stdout, fmt, ap);
+}
+
+int __vsnprintf_chk(char *s, size_t n, int flag, size_t slen, const char *fmt, va_list ap)
+{
+	if (n > slen) a_crash();
+	return vsnprintf(s, n, fmt, ap);
+}
+
+int __vsprintf_chk(char *s, int flag, size_t slen, const char *fmt, va_list ap)
+{
+	int ret;
+	if (slen == 0) a_crash();
+	ret = vsnprintf(s, slen, fmt, ap);
+	if (ret > slen) a_crash();
+	return ret;
+}
diff --git a/src/compat/realpath_chk.c b/src/compat/realpath_chk.c
new file mode 100644
index 0000000..cc0089e
--- /dev/null
+++ b/src/compat/realpath_chk.c
@@ -0,0 +1,9 @@
+#include <stdlib.h>
+#include <limits.h>
+#include "atomics.h"
+
+char *__realpath_chk(const char *filename, char *resolved, size_t resolved_len)
+{
+	if (resolved_len < PATH_MAX) a_crash();
+	return realpath(filename, resolved);
+}
diff --git a/src/compat/stdio_chk.c b/src/compat/stdio_chk.c
new file mode 100644
index 0000000..53e514c
--- /dev/null
+++ b/src/compat/stdio_chk.c
@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <wchar.h>
+#include "atomic.h"
+#include "libc.h"
+#include "stdio_impl.h"
+
+char *__fgets_chk(char *s, size_t size, int n, FILE *f)
+{
+	if ((size_t)n > size) a_crash();
+	return fgets(s, n, f);
+}
+
+wchar_t *__fgetws_chk(wchar_t *s, size_t size, int n, FILE *f)
+{
+	if ((size_t)n > size) a_crash();
+	return fgetws(s, n, f);
+}
+
+size_t __fread_chk(void *restrict destv, size_t destvlen, size_t size, size_t nmemb, FILE *restrict f)
+{
+	if (size != 0 && (size * nmemb) / size != nmemb) a_crash();
+	if (size * nmemb > destvlen) a_crash();
+	return fread(destv, size, nmemb, f);
+}
+
+char *__gets_chk(char *buf, size_t size)
+{
+	char *ret = buf;
+	int c;
+	FLOCK(stdin);
+	if (!size) return NULL;
+	for(;size;buf++,size--) {
+		c = getc(stdin);
+		if ((c == EOF && feof(stdin)) || c == '\n') {
+			*buf = 0;
+			FUNLOCK(stdin);
+			return ret;
+		}
+		if (c == EOF) {
+			FUNLOCK(stdin);
+			return NULL;
+		}
+		*buf = c;
+	}
+	a_crash();
+}
+
+weak_alias(__fgets_chk, __fgets_unlocked_chk);
+weak_alias(__fgetws_chk, __fgetws_unlocked_chk);
+weak_alias(__fread_chk, __fread_unlocked_chk);
diff --git a/src/compat/string_chk.c b/src/compat/string_chk.c
new file mode 100644
index 0000000..ba77c9c
--- /dev/null
+++ b/src/compat/string_chk.c
@@ -0,0 +1,98 @@
+#include <string.h>
+#include <wchar.h>
+#include "atomic.h"
+
+void *__memcpy_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
+{
+	if (n > destlen) a_crash();
+	return memcpy(dest, src, n);
+}
+
+void *__memmove_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
+{
+	if (n > destlen) a_crash();
+	return memmove(dest, src, n);
+}
+
+void *__memset_chk(void *dest, int c, size_t n, size_t destlen)
+{
+	if (n > destlen) a_crash();
+	return memset(dest, c, n);
+}
+
+char *__strcat_chk(char *restrict dest, const char *restrict src, size_t destlen)
+{
+	size_t tot;
+	tot = strnlen(src, destlen);
+	if (tot > SIZE_MAX - strnlen(dest, destlen) - 1) a_crash();
+	tot += strnlen(dest, destlen) + 1;
+	if (tot > destlen) a_crash();
+	return strcat(dest, src);
+}
+
+char *__strncat_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
+{
+	size_t tot;
+	tot = strnlen(dest, destlen);
+	if (tot > SIZE_MAX - strnlen(src, n) - 1) a_crash();
+	tot += strnlen(src, n) + 1;
+	if (tot > destlen) a_crash();
+	return strncat(dest, src, n);
+}
+
+char *__strncpy_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
+{
+	if (n > destlen) a_crash();
+	return strncpy(dest, src, n);
+}
+
+wchar_t *__wcscat_chk(wchar_t *restrict dest, const wchar_t *src, size_t destlen)
+{
+	size_t tot;
+	tot = wcsnlen(src, destlen);
+	if (tot > SIZE_MAX - wcsnlen(dest, destlen) - 1) a_crash();
+	tot += wcsnlen(dest, destlen) + 1;
+	if (tot > destlen) a_crash();
+	return wcscat(dest, src);
+}
+
+wchar_t *__wcscpy_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t destlen)
+{
+	size_t srclen = wcsnlen(src, destlen) + 1;
+	if (srclen > destlen) a_crash();
+	return wcscpy(dest, src);
+}
+
+wchar_t *__wcsncat_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
+{
+	size_t tot;
+	tot = wcsnlen(dest, destlen);
+	if (tot > SIZE_MAX - wcsnlen(src, n) - 1) a_crash();
+	tot += wcsnlen(dest, destlen) + 1;
+	if (tot > destlen) a_crash();
+	return wcsncat(dest, src, n);
+}
+
+wchar_t *__wcsncpy_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
+{
+	if (n > destlen) a_crash();
+	return wcsncpy(dest, src, n);
+}
+
+wchar_t *__wmemcpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t n, size_t dlen)
+{
+	if (n > dlen) a_crash();
+	return wmemcpy(d, s, n);
+}
+
+wchar_t *__wmemmove_chk(wchar_t *d, const wchar_t *s, size_t n, size_t dlen)
+{
+	if (n > dlen) a_crash();
+	return wmemmove(d, s, n);
+}
+
+wchar_t *__wmemset_chk(wchar_t *d, wchar_t c, size_t n, size_t dlen)
+{
+	if (n > dlen) a_crash();
+	return wmemset(d, c, n);
+}
diff --git a/src/compat/syslog_chk.c b/src/compat/syslog_chk.c
new file mode 100644
index 0000000..57c7775
--- /dev/null
+++ b/src/compat/syslog_chk.c
@@ -0,0 +1,17 @@
+#include <syslog.h>
+#include <stdarg.h>
+
+void __vsyslog(int, const char *, va_list);
+
+void __syslog_chk(int priority, int flag, const char *message, ...)
+{
+	va_list ap;
+	va_start(ap, message);
+	__vsyslog(priority, message, ap);
+	va_end(ap);
+}
+
+void __vsyslog_chk(int priority, int flag, const char *message, va_list ap)
+{
+	__vsyslog(priority, message, ap);
+}
diff --git a/src/compat/ttyname_r_chk.c b/src/compat/ttyname_r_chk.c
new file mode 100644
index 0000000..50e70e5
--- /dev/null
+++ b/src/compat/ttyname_r_chk.c
@@ -0,0 +1,7 @@
+#include <unistd.h>
+
+int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
+{
+	if (size > namelen) a_crash();
+	return ttyname_r(fd, name, size);
+}
diff --git a/src/compat/wchar_chk.c b/src/compat/wchar_chk.c
new file mode 100644
index 0000000..66e35b1
--- /dev/null
+++ b/src/compat/wchar_chk.c
@@ -0,0 +1,45 @@
+#include <wchar.h>
+#include <stdlib.h>
+#include "atomic.h"
+
+size_t __mbsnrtowcs_chk(wchar_t *restrict wcs, const char **restrict src, size_t n, size_t wn, mbstate_t *restrict st, size_t wcslen)
+{
+	if (wn > wcslen) a_crash();
+	return msbnrtowcs(wcs, src, n, wn, st);
+}
+
+size_t __mbsrtowcs_chk(wchar_t *restrict ws, const char **restrict src, size_t wn, mbstate_t *restrict st, size_t wslen)
+{
+	if (wn > wslen) a_crash();
+	return mbsrtowcs(ws, src, wn, st);
+}
+
+size_t __mbstowcs_chk(wchar_t *restrict ws, const char *restrict s, size_t wn, size_t wslen)
+{
+	if (wn > wslen) a_crash();
+	return mbstowcs(ws, s, wn);
+}
+
+size_t __wcrtomb_chk(char *restrict s, wchar_t wc, mbstate_t *restrict st, size_t slen)
+{
+	if (slen < MB_CUR_MAX) a_crash();
+	return wcrtomb(s, wc, st);
+}
+
+size_t __wcsnrtombs_chk(char *restrict dst, const wchar_t **restrict wcs, size_t wn, size_t n, mbstate_t *restrict st, size_t dstlen)
+{
+	if (n > dstlen) a_crash();
+	return wcsnrtombs(dst, wcs, wn, n, st);
+}
+
+size_t __wcstombs_chk(char *restrict s, const wchar_t *restrict ws, size_t n, size_t slen)
+{
+	if (n > slen) a_crash();
+	return wcstombs(s, ws, n);
+}
+
+int __wctomb_chk(char *s, wchar_t wc, size_t slen)
+{
+	if (slen < MB_CUR_MAX) a_crash();
+	return wctomb(s, wc);
+}
diff --git a/src/compat/wprintf_chk.c b/src/compat/wprintf_chk.c
new file mode 100644
index 0000000..cd84798
--- /dev/null
+++ b/src/compat/wprintf_chk.c
@@ -0,0 +1,51 @@
+#include <wchar.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include "atomic.h"
+
+int __fwprintf_chk(FILE *restrict f, int flag, const wchar_t *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vfwprintf(f, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __swprintf_chk(wchar_t *restrict s, size_t n, int flag, size_t slen, const wchar_t *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	if (n > slen) a_crash();
+	va_start(ap, fmt);
+	ret = vswprintf(s, n, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __wprintf_chk(int flag, const wchar_t *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vfwprintf(stdout, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
+int __vfwprintf_chk(FILE *f, int flag, const wchar_t *restrict fmt, va_list ap)
+{
+	return vfwprintf(f, fmt, ap);
+}
+
+int __vswprintf_chk(wchar_t *restrict s, size_t n, int flag, size_t slen, const wchar_t *restrict fmt, va_list ap)
+{
+	if (n > slen) a_crash();
+	return vswprintf(s, n, fmt, ap);
+}
+
+int __vwprintf_chk(int flag, const wchar_t *restrict fmt, va_list ap)
+{
+	return vfwprintf(stdout, fmt, ap);
+}
-- 
2.1.4

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Szabolcs Nagy]

* Josiah Worcester <josiahw@gmail.com> [2015-06-16 21:48:11 -0500]:
> --- /dev/null
> +++ b/src/compat/gnu_chk.c
> @@ -0,0 +1,18 @@
> +#define _GNU_SOURCE
> +#include <string.h>
> +#include <poll.h>
> +#include <stddef.h>
> +#include "atomic.h"
> +#include "atomic.h"
> +
> +int __ppoll_chk(struct pollfd *fds, nfds_t n, const struct timespec *to, const sigset_t *mask, size_t fdslen)
> +{
> +	if (fdslen / sizeof(*fds) < n) a_crash();
> +	return ppoll(fds, n, to, mask);
> +}
> +
> +void *__mempcpy_chk(void *dest, const void *src, size_t n, size_t destlen)
> +{
> +	if (destlen < n) a_crash();
> +	return mempcpy(dest, src, n);
> +}

one atomic is enough

> +char *__gets_chk(char *buf, size_t size)
> +{
> +	char *ret = buf;
> +	int c;
> +	FLOCK(stdin);
> +	if (!size) return NULL;
> +	for(;size;buf++,size--) {
> +		c = getc(stdin);
> +		if ((c == EOF && feof(stdin)) || c == '\n') {
> +			*buf = 0;
> +			FUNLOCK(stdin);
> +			return ret;
> +		}
> +		if (c == EOF) {
> +			FUNLOCK(stdin);
> +			return NULL;
> +		}
> +		*buf = c;
> +	}
> +	a_crash();
> +}

this looks wrong if !size

i think that line should be just removed

> +void *__memmove_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return memmove(dest, src, n);
> +}

i think restrict is wrong here

> +char *__strcat_chk(char *restrict dest, const char *restrict src, size_t destlen)
> +{
> +	size_t tot;
> +	tot = strnlen(src, destlen);
> +	if (tot > SIZE_MAX - strnlen(dest, destlen) - 1) a_crash();
> +	tot += strnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return strcat(dest, src);
> +}
> +
> +char *__strncat_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
> +{
> +	size_t tot;
> +	tot = strnlen(dest, destlen);
> +	if (tot > SIZE_MAX - strnlen(src, n) - 1) a_crash();
> +	tot += strnlen(src, n) + 1;
> +	if (tot > destlen) a_crash();
> +	return strncat(dest, src, n);
> +}
> +

i'd store the strnlen result in a temporary var

musl is built with -ffreestanding so the compiler cannot
assume strnlen is a pure function.

> +wchar_t *__wcscat_chk(wchar_t *restrict dest, const wchar_t *src, size_t destlen)
> +{
> +	size_t tot;
> +	tot = wcsnlen(src, destlen);
> +	if (tot > SIZE_MAX - wcsnlen(dest, destlen) - 1) a_crash();
> +	tot += wcsnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return wcscat(dest, src);
> +}
> +
> +wchar_t *__wcsncat_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
> +{
> +	size_t tot;
> +	tot = wcsnlen(dest, destlen);
> +	if (tot > SIZE_MAX - wcsnlen(src, n) - 1) a_crash();
> +	tot += wcsnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return wcsncat(dest, src, n);
> +}
> +

ditto

> diff --git a/src/compat/ttyname_r_chk.c b/src/compat/ttyname_r_chk.c
> new file mode 100644
> index 0000000..50e70e5
> --- /dev/null
> +++ b/src/compat/ttyname_r_chk.c
> @@ -0,0 +1,7 @@
> +#include <unistd.h>
> +
> +int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
> +{
> +	if (size > namelen) a_crash();
> +	return ttyname_r(fd, name, size);
> +}

missing atomic.h for a_crash

shouldnt this be in posix_chk.c?

> +size_t __wcrtomb_chk(char *restrict s, wchar_t wc, mbstate_t *restrict st, size_t slen)
> +{
> +	if (slen < MB_CUR_MAX) a_crash();
> +	return wcrtomb(s, wc, st);
> +}

i think this can cause a false positive crash
but glibc seems to do the same..

(eg some api passes wchar_t* and the exact mb encoded length of
a string so the output s can be safely shorter than max mb length)

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Josiah Worcester]

On Wed, Jun 17, 2015 at 4:30 AM, Szabolcs Nagy <nsz@port70.net> wrote:
> * Josiah Worcester <josiahw@gmail.com> [2015-06-16 21:48:11 -0500]:
>> --- /dev/null
>> +++ b/src/compat/gnu_chk.c
>> @@ -0,0 +1,18 @@
>> +#define _GNU_SOURCE
>> +#include <string.h>
>> +#include <poll.h>
>> +#include <stddef.h>
>> +#include "atomic.h"
>> +#include "atomic.h"
>> +
>> +int __ppoll_chk(struct pollfd *fds, nfds_t n, const struct timespec *to, const sigset_t *mask, size_t fdslen)
>> +{
>> +     if (fdslen / sizeof(*fds) < n) a_crash();
>> +     return ppoll(fds, n, to, mask);
>> +}
>> +
>> +void *__mempcpy_chk(void *dest, const void *src, size_t n, size_t destlen)
>> +{
>> +     if (destlen < n) a_crash();
>> +     return mempcpy(dest, src, n);
>> +}
>
> one atomic is enough
>

Ooops.

>> +char *__gets_chk(char *buf, size_t size)
>> +{
>> +     char *ret = buf;
>> +     int c;
>> +     FLOCK(stdin);
>> +     if (!size) return NULL;
>> +     for(;size;buf++,size--) {
>> +             c = getc(stdin);
>> +             if ((c == EOF && feof(stdin)) || c == '\n') {
>> +                     *buf = 0;
>> +                     FUNLOCK(stdin);
>> +                     return ret;
>> +             }
>> +             if (c == EOF) {
>> +                     FUNLOCK(stdin);
>> +                     return NULL;
>> +             }
>> +             *buf = c;
>> +     }
>> +     a_crash();
>> +}
>
> this looks wrong if !size
>
> i think that line should be just removed
>

Hmm, yeah.  When the buffer is empty it should crash, not just report error.

>> +void *__memmove_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
>> +{
>> +     if (n > destlen) a_crash();
>> +     return memmove(dest, src, n);
>> +}
>
> i think restrict is wrong here
>

It is.

>> +char *__strcat_chk(char *restrict dest, const char *restrict src, size_t destlen)
>> +{
>> +     size_t tot;
>> +     tot = strnlen(src, destlen);
>> +     if (tot > SIZE_MAX - strnlen(dest, destlen) - 1) a_crash();
>> +     tot += strnlen(dest, destlen) + 1;
>> +     if (tot > destlen) a_crash();
>> +     return strcat(dest, src);
>> +}
>> +
>> +char *__strncat_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
>> +{
>> +     size_t tot;
>> +     tot = strnlen(dest, destlen);
>> +     if (tot > SIZE_MAX - strnlen(src, n) - 1) a_crash();
>> +     tot += strnlen(src, n) + 1;
>> +     if (tot > destlen) a_crash();
>> +     return strncat(dest, src, n);
>> +}
>> +
>
> i'd store the strnlen result in a temporary var
>
> musl is built with -ffreestanding so the compiler cannot
> assume strnlen is a pure function.

Good call. In common use it won't matter much, but that's potentially
an extra string iteration for no good reason.

>> +wchar_t *__wcscat_chk(wchar_t *restrict dest, const wchar_t *src, size_t destlen)
>> +{
>> +     size_t tot;
>> +     tot = wcsnlen(src, destlen);
>> +     if (tot > SIZE_MAX - wcsnlen(dest, destlen) - 1) a_crash();
>> +     tot += wcsnlen(dest, destlen) + 1;
>> +     if (tot > destlen) a_crash();
>> +     return wcscat(dest, src);
>> +}
>> +
>> +wchar_t *__wcsncat_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
>> +{
>> +     size_t tot;
>> +     tot = wcsnlen(dest, destlen);
>> +     if (tot > SIZE_MAX - wcsnlen(src, n) - 1) a_crash();
>> +     tot += wcsnlen(dest, destlen) + 1;
>> +     if (tot > destlen) a_crash();
>> +     return wcsncat(dest, src, n);
>> +}
>> +
>
> ditto
>
>> diff --git a/src/compat/ttyname_r_chk.c b/src/compat/ttyname_r_chk.c
>> new file mode 100644
>> index 0000000..50e70e5
>> --- /dev/null
>> +++ b/src/compat/ttyname_r_chk.c
>> @@ -0,0 +1,7 @@
>> +#include <unistd.h>
>> +
>> +int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
>> +{
>> +     if (size > namelen) a_crash();
>> +     return ttyname_r(fd, name, size);
>> +}
>
> missing atomic.h for a_crash

Oops.

> shouldnt this be in posix_chk.c?

This... I swear I deleted this file before making the patch. It's an
old development fragment. The one I actually care about is in
posix_chk.c.

>> +size_t __wcrtomb_chk(char *restrict s, wchar_t wc, mbstate_t *restrict st, size_t slen)
>> +{
>> +     if (slen < MB_CUR_MAX) a_crash();
>> +     return wcrtomb(s, wc, st);
>> +}
>
> i think this can cause a false positive crash
> but glibc seems to do the same..
>
> (eg some api passes wchar_t* and the exact mb encoded length of
> a string so the output s can be safely shorter than max mb length)
>
I'm not sure if we should match glibc here or do a better check.

Thanks for the input. I'm going to wait a bit before posting a new
patch, though, in hopes that more comments are forthcoming.

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Rich Felker]

On Wed, Jun 17, 2015 at 02:07:08PM -0500, Josiah Worcester wrote:
> >> +size_t __wcrtomb_chk(char *restrict s, wchar_t wc, mbstate_t *restrict st, size_t slen)
> >> +{
> >> +     if (slen < MB_CUR_MAX) a_crash();
> >> +     return wcrtomb(s, wc, st);
> >> +}
> >
> > i think this can cause a false positive crash
> > but glibc seems to do the same..
> >
> > (eg some api passes wchar_t* and the exact mb encoded length of
> > a string so the output s can be safely shorter than max mb length)
> >
> I'm not sure if we should match glibc here or do a better check.
> 
> Thanks for the input. I'm going to wait a bit before posting a new
> patch, though, in hopes that more comments are forthcoming.

This code is definitely wrong as-is; for example:

	char c;
	wcrtomb(&c, L'0', st)

is perfectly valid (albeit useless) code. Other examples are possible
too. I think a decent check would be:

	size_t r = wcrtomb(s, wc, st);
	if (r+1 > slen+1) a_crash();
	return r;

This allows an overflow of up to 3 bytes to occur before the trap, but
there's no way a valid dest buffer could be within 3 bytes of this
function's or wcrtomb's stack, so you should safely reach the a_crash
even on overflow.

The alternative would be using a temp buffer of size MB_LEN_MAX and
then performing memcpy to the caller's buffer if the result fits or
a_crash if not.

Rich

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Rich Felker]

On Tue, Jun 16, 2015 at 09:48:11PM -0500, Josiah Worcester wrote:
> diff --git a/src/compat/confstr_chk.c b/src/compat/confstr_chk.c
> new file mode 100644
> index 0000000..61bcd42
> --- /dev/null
> +++ b/src/compat/confstr_chk.c
> @@ -0,0 +1,8 @@
> +#include <unistd.h>
> +#include <atomic.h>
> +
> +size_t __confstr_chk(int name, char *buf, size_t len, size_t buflen)
> +{
> +	if (buflen < len) a_crash();
> +	return confstr(name, buf, len);
> +}

I think this should be something like:

	size_t r = confstr(name, buf, len<buflen ? len : buflen);
	if (buflen < len && r < buflen) a_crash();
	return r;

i.e. you should not crash unless the overflow actually would happen.

> diff --git a/src/compat/posix_chk.c b/src/compat/posix_chk.c
> new file mode 100644
> index 0000000..7e39754
> --- /dev/null
> +++ b/src/compat/posix_chk.c
> @@ -0,0 +1,132 @@
> +#include <poll.h>
> +#include <sys/socket.h>
> +#include <unistd.h>
> +#include <fcntl.h>
> +#include <string.h>
> +#include <wchar.h>
> +#include "atomic.h"
> +
> +ssize_t __read_chk(int fd, void *buf, size_t count, size_t buflen)
> +{
> +	if (count > buflen) a_crash();
> +	return read(fd, buf, count);
> +}
> +
> +ssize_t __readlink_chk(const char *path, void *buf, size_t bufsize, size_t buflen)
> +{
> +	if (bufsize > buflen) a_crash();
> +	return readlink(path, buf, bufsize);
> +}
> +
> +ssize_t __readlinkat_chk(int fd, const char *path, void *buf, size_t bufsize, size_t buflen)
> +{
> +	if (bufsize > buflen) a_crash();
> +	return readlinkat(fd, path, buf, bufsize);
> +}
> +
> +ssize_t __recv_chk(int fd, void *buf, size_t len, size_t buflen, int flags)
> +{
> +	if (len > buflen) a_crash();
> +	return recv(fd, buf, len, flags);
> +}
> +
> +ssize_t __recvfrom_chk(int fd, void *buf, size_t len, size_t buflen, int flags, struct sockaddr *addr, socklen_t *alen)
> +{
> +	if (len > buflen) a_crash();
> +	return recvfrom(fd, buf, len, flags, addr, alen);
> +}
> +

These all have the same issue as confstr, and need the same fix.

> +ssize_t __pread_chk(int fd, void *buf, size_t size, size_t ofs, size_t buflen)
> +{
> +	if (size > buflen) a_crash();
> +	return pread(fd, buf, size, ofs);
> +}
> +
> +ssize_t __pread64_chk(int fd, void *buf, size_t size, size_t ofs, size_t buflen)
> +{
> +	return __pread_chk(fd, buf, size, ofs, buflen);
> +}
> +

These too.

> +char *__getcwd_chk(char *buf, size_t len, size_t buflen)
> +{
> +	if (len > buflen) a_crash();
> +	return getcwd(buf, len);
> +}

And again. Here there's also the case of !buf in which case len is ignored.

> +int __gethostname_chk(char *name, size_t len, size_t namelen)
> +{
> +	if (len > namelen) a_crash();
> +	return gethostname(name, len);
> +}

Same issue.

> +int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
> +{
> +	if (size > namelen) a_crash();
> +	return ttyname_r(fd, name, size);
> +}

Same.

> +char *__stpcpy_chk(char *d, const char *s, size_t dlen)
> +{
> +	size_t slen = strnlen(s, dlen) + 1;
> +	if (slen > dlen) a_crash();
> +	return stpcpy(d, s);
> +}

This looks like it handles the issue right.

> +char *__stpncpy_chk(char *d, const char *s, size_t n, size_t dlen)
> +{
> +	if (n > dlen) a_crash();
> +	return stpncpy(d, s, n);
> +}

But this does it wrong again.

> +wchar_t *__wcpcpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t dlen)
> +{
> +	size_t slen = strnlen(s, dlen) + 1;
> +	if (slen > dlen) a_crash();
> +	return wcpcpy(d, s);
> +}

strnlen is obviously wrong for wchar_t * input. Please try compiling
with the -Werror options musl uses by default which will catch invalid
C like this. The check looks right though with that fixed.

> +wchar_t *__wcpncpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t n, size_t dlen)
> +{
> +	if (n > dlen) a_crash();
> +	return wcpncpy(d, s, n);
> +}

Same issue again.

> +int __vsnprintf_chk(char *s, size_t n, int flag, size_t slen, const char *fmt, va_list ap)
> +{
> +	if (n > slen) a_crash();
> +	return vsnprintf(s, n, fmt, ap);
> +}

And again here.

> +int __vsprintf_chk(char *s, int flag, size_t slen, const char *fmt, va_list ap)
> +{
> +	int ret;
> +	if (slen == 0) a_crash();
> +	ret = vsnprintf(s, slen, fmt, ap);
> +	if (ret > slen) a_crash();
> +	return ret;
> +}

That should be ret>=slen, because ret does not include the null
termination. But you also need to avoid crashing when ret<0, which is
a valid error return. The implicit conversion to size_t would make all
errors crash because -1 is > any size_t except SIZE_MAX.

> diff --git a/src/compat/realpath_chk.c b/src/compat/realpath_chk.c
> new file mode 100644
> index 0000000..cc0089e
> --- /dev/null
> +++ b/src/compat/realpath_chk.c
> @@ -0,0 +1,9 @@
> +#include <stdlib.h>
> +#include <limits.h>
> +#include "atomics.h"
> +
> +char *__realpath_chk(const char *filename, char *resolved, size_t resolved_len)
> +{
> +	if (resolved_len < PATH_MAX) a_crash();
> +	return realpath(filename, resolved);
> +}

Aside from having the same issue as above, this ignores the case of
passing a null pointer, which is always valid. I think the only way to
make this function safe is to use a temp buffer of size PATH_MAX on
the stack and memcpy the result or crash if strlen is > PATH_MAX.

> diff --git a/src/compat/stdio_chk.c b/src/compat/stdio_chk.c
> new file mode 100644
> index 0000000..53e514c
> --- /dev/null
> +++ b/src/compat/stdio_chk.c
> @@ -0,0 +1,50 @@
> +#include <stdio.h>
> +#include <wchar.h>
> +#include "atomic.h"
> +#include "libc.h"
> +#include "stdio_impl.h"
> +
> +char *__fgets_chk(char *s, size_t size, int n, FILE *f)
> +{
> +	if ((size_t)n > size) a_crash();
> +	return fgets(s, n, f);
> +}
> +
> +wchar_t *__fgetws_chk(wchar_t *s, size_t size, int n, FILE *f)
> +{
> +	if ((size_t)n > size) a_crash();
> +	return fgetws(s, n, f);
> +}
> +
> +size_t __fread_chk(void *restrict destv, size_t destvlen, size_t size, size_t nmemb, FILE *restrict f)
> +{
> +	if (size != 0 && (size * nmemb) / size != nmemb) a_crash();
> +	if (size * nmemb > destvlen) a_crash();
> +	return fread(destv, size, nmemb, f);
> +}

Same issue in these.

> +char *__gets_chk(char *buf, size_t size)
> +{
> +	char *ret = buf;
> +	int c;
> +	FLOCK(stdin);
> +	if (!size) return NULL;
> +	for(;size;buf++,size--) {
> +		c = getc(stdin);
> +		if ((c == EOF && feof(stdin)) || c == '\n') {
> +			*buf = 0;
> +			FUNLOCK(stdin);
> +			return ret;
> +		}
> +		if (c == EOF) {
> +			FUNLOCK(stdin);
> +			return NULL;
> +		}
> +		*buf = c;
> +	}
> +	a_crash();
> +}

I would mildly prefer using flockfile/funlockfile (POSIX namespace) to
using stdio internals here, but it's not a big deal. gets is no longer
in the C namespace so that seems valid to me (as long as it's moved).

> diff --git a/src/compat/string_chk.c b/src/compat/string_chk.c
> new file mode 100644
> index 0000000..ba77c9c
> --- /dev/null
> +++ b/src/compat/string_chk.c
> @@ -0,0 +1,98 @@
> +#include <string.h>
> +#include <wchar.h>
> +#include "atomic.h"
> +
> +void *__memcpy_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return memcpy(dest, src, n);
> +}
> +
> +void *__memmove_chk(void *restrict dest, const void *restrict src, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return memmove(dest, src, n);
> +}
> +
> +void *__memset_chk(void *dest, int c, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return memset(dest, c, n);
> +}

These are okay because they write exact-length n.

> +char *__strcat_chk(char *restrict dest, const char *restrict src, size_t destlen)
> +{
> +	size_t tot;
> +	tot = strnlen(src, destlen);
> +	if (tot > SIZE_MAX - strnlen(dest, destlen) - 1) a_crash();
> +	tot += strnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return strcat(dest, src);
> +}
> +
> +char *__strncat_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
> +{
> +	size_t tot;
> +	tot = strnlen(dest, destlen);
> +	if (tot > SIZE_MAX - strnlen(src, n) - 1) a_crash();
> +	tot += strnlen(src, n) + 1;
> +	if (tot > destlen) a_crash();
> +	return strncat(dest, src, n);
> +}

I think these are right but I'll review them again before commit.

> +char *__strncpy_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return strncpy(dest, src, n);
> +}

This is okay because strncpy is an exact-length n write.

> +wchar_t *__wcscat_chk(wchar_t *restrict dest, const wchar_t *src, size_t destlen)
> +{
> +	size_t tot;
> +	tot = wcsnlen(src, destlen);
> +	if (tot > SIZE_MAX - wcsnlen(dest, destlen) - 1) a_crash();
> +	tot += wcsnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return wcscat(dest, src);
> +}
> +
> +wchar_t *__wcscpy_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t destlen)
> +{
> +	size_t srclen = wcsnlen(src, destlen) + 1;
> +	if (srclen > destlen) a_crash();
> +	return wcscpy(dest, src);
> +}
> +
> +wchar_t *__wcsncat_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
> +{
> +	size_t tot;
> +	tot = wcsnlen(dest, destlen);
> +	if (tot > SIZE_MAX - wcsnlen(src, n) - 1) a_crash();
> +	tot += wcsnlen(dest, destlen) + 1;
> +	if (tot > destlen) a_crash();
> +	return wcsncat(dest, src, n);
> +}
> +
> +wchar_t *__wcsncpy_chk(wchar_t *restrict dest, const wchar_t *restrict src, size_t n, size_t destlen)
> +{
> +	if (n > destlen) a_crash();
> +	return wcsncpy(dest, src, n);
> +}
> +
> +wchar_t *__wmemcpy_chk(wchar_t *restrict d, const wchar_t *restrict s, size_t n, size_t dlen)
> +{
> +	if (n > dlen) a_crash();
> +	return wmemcpy(d, s, n);
> +}
> +
> +wchar_t *__wmemmove_chk(wchar_t *d, const wchar_t *s, size_t n, size_t dlen)
> +{
> +	if (n > dlen) a_crash();
> +	return wmemmove(d, s, n);
> +}
> +
> +wchar_t *__wmemset_chk(wchar_t *d, wchar_t c, size_t n, size_t dlen)
> +{
> +	if (n > dlen) a_crash();
> +	return wmemset(d, c, n);
> +}

I didn't notice any problem in the rest of these.

> diff --git a/src/compat/ttyname_r_chk.c b/src/compat/ttyname_r_chk.c
> new file mode 100644
> index 0000000..50e70e5
> --- /dev/null
> +++ b/src/compat/ttyname_r_chk.c
> @@ -0,0 +1,7 @@
> +#include <unistd.h>
> +
> +int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
> +{
> +	if (size > namelen) a_crash();
> +	return ttyname_r(fd, name, size);
> +}

Same issue again.

> diff --git a/src/compat/wchar_chk.c b/src/compat/wchar_chk.c
> new file mode 100644
> index 0000000..66e35b1
> --- /dev/null
> +++ b/src/compat/wchar_chk.c
> @@ -0,0 +1,45 @@
> +#include <wchar.h>
> +#include <stdlib.h>
> +#include "atomic.h"
> +
> +size_t __mbsnrtowcs_chk(wchar_t *restrict wcs, const char **restrict src, size_t n, size_t wn, mbstate_t *restrict st, size_t wcslen)
> +{
> +	if (wn > wcslen) a_crash();
> +	return msbnrtowcs(wcs, src, n, wn, st);
> +}
> +
> +size_t __mbsrtowcs_chk(wchar_t *restrict ws, const char **restrict src, size_t wn, mbstate_t *restrict st, size_t wslen)
> +{
> +	if (wn > wslen) a_crash();
> +	return mbsrtowcs(ws, src, wn, st);
> +}
> +
> +size_t __mbstowcs_chk(wchar_t *restrict ws, const char *restrict s, size_t wn, size_t wslen)
> +{
> +	if (wn > wslen) a_crash();
> +	return mbstowcs(ws, s, wn);
> +}
> +
> +size_t __wcrtomb_chk(char *restrict s, wchar_t wc, mbstate_t *restrict st, size_t slen)
> +{
> +	if (slen < MB_CUR_MAX) a_crash();
> +	return wcrtomb(s, wc, st);
> +}
> +
> +size_t __wcsnrtombs_chk(char *restrict dst, const wchar_t **restrict wcs, size_t wn, size_t n, mbstate_t *restrict st, size_t dstlen)
> +{
> +	if (n > dstlen) a_crash();
> +	return wcsnrtombs(dst, wcs, wn, n, st);
> +}
> +
> +size_t __wcstombs_chk(char *restrict s, const wchar_t *restrict ws, size_t n, size_t slen)
> +{
> +	if (n > slen) a_crash();
> +	return wcstombs(s, ws, n);
> +}
> +
> +int __wctomb_chk(char *s, wchar_t wc, size_t slen)
> +{
> +	if (slen < MB_CUR_MAX) a_crash();
> +	return wctomb(s, wc);
> +}

And all of these.

Rich

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Rich Felker]

Any progress on this?

Rich

Re: [PATCH] Implement glibc *_chk interfaces for ABI compatibility.

[Isaac Dunham]

[-- Attachment #1: Type: text/plain, Size: 297 bytes --]

Not a fix for the issues discussed, but some compile issues and one
missing function.
I did this in the process of making the ksh93 binary from Debian
run on Alpine (there are a few other functions I've done rather
hackish stubs for, mostly math stuff; but that's another matter.)

Thanks,
Isaac


[-- Attachment #2: 0001-src-compat-_chk.c-fix-build-add-__strcpy_chk.patch --]
[-- Type: text/plain, Size: 3232 bytes --]

From 3a9fdda5680fed183f0b33a9412fb88e0cb8f6a8 Mon Sep 17 00:00:00 2001
From: Isaac Dunham <ibid.ag@gmail.com>
Date: Tue, 30 Jun 2015 21:06:20 -0700
Subject: [PATCH] src/compat/*_chk.c: fix build, add __strcpy_chk()

---
 src/compat/longjmp_chk.c   | 4 ++--
 src/compat/posix_chk.c     | 7 +------
 src/compat/realpath_chk.c  | 2 +-
 src/compat/string_chk.c    | 6 ++++++
 src/compat/ttyname_r_chk.c | 1 +
 src/compat/wchar_chk.c     | 2 +-
 6 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/src/compat/longjmp_chk.c b/src/compat/longjmp_chk.c
index e814ecc..576a1b5 100644
--- a/src/compat/longjmp_chk.c
+++ b/src/compat/longjmp_chk.c
@@ -1,7 +1,7 @@
 #include <setjmp.h>
 #include <signal.h>
 
-_Noreturn void __longjmp_chk(sigjmp_buf buf, int ret)
+_Noreturn void __longjmp_chk(jmp_buf buf, int ret)
 {
-	longjmp((jmp_buf)buf, ret);
+	longjmp(buf, ret);
 }
diff --git a/src/compat/posix_chk.c b/src/compat/posix_chk.c
index 7e39754..2b9a845 100644
--- a/src/compat/posix_chk.c
+++ b/src/compat/posix_chk.c
@@ -1,3 +1,4 @@
+#include <sys/select.h>
 #include <poll.h>
 #include <sys/socket.h>
 #include <unistd.h>
@@ -93,12 +94,6 @@ long __fdelt_chk(long d)
 	return d / (8 * sizeof(d));
 }
 
-int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
-{
-	if (size > namelen) a_crash();
-	return ttyname_r(fd, name, size);
-}
-
 char *__stpcpy_chk(char *d, const char *s, size_t dlen)
 {
 	size_t slen = strnlen(s, dlen) + 1;
diff --git a/src/compat/realpath_chk.c b/src/compat/realpath_chk.c
index cc0089e..c2ac9f8 100644
--- a/src/compat/realpath_chk.c
+++ b/src/compat/realpath_chk.c
@@ -1,6 +1,6 @@
 #include <stdlib.h>
 #include <limits.h>
-#include "atomics.h"
+#include "atomic.h"
 
 char *__realpath_chk(const char *filename, char *resolved, size_t resolved_len)
 {
diff --git a/src/compat/string_chk.c b/src/compat/string_chk.c
index ba77c9c..8a17c48 100644
--- a/src/compat/string_chk.c
+++ b/src/compat/string_chk.c
@@ -40,6 +40,12 @@ char *__strncat_chk(char *restrict dest, const char *restrict src, size_t n, siz
 	return strncat(dest, src, n);
 }
 
+char *__strcpy_chk(char *restrict dest, const char *restrict src, size_t destlen)
+{
+	if ( strlen(src) >= destlen) a_crash();
+	return strcpy(dest, src);
+}
+
 char *__strncpy_chk(char *restrict dest, const char *restrict src, size_t n, size_t destlen)
 {
 	if (n > destlen) a_crash();
diff --git a/src/compat/ttyname_r_chk.c b/src/compat/ttyname_r_chk.c
index 50e70e5..cbede51 100644
--- a/src/compat/ttyname_r_chk.c
+++ b/src/compat/ttyname_r_chk.c
@@ -1,4 +1,5 @@
 #include <unistd.h>
+#include "atomic.h"
 
 int __ttyname_r_chk(int fd, char *name, size_t size, size_t namelen)
 {
diff --git a/src/compat/wchar_chk.c b/src/compat/wchar_chk.c
index 66e35b1..fd5b075 100644
--- a/src/compat/wchar_chk.c
+++ b/src/compat/wchar_chk.c
@@ -5,7 +5,7 @@
 size_t __mbsnrtowcs_chk(wchar_t *restrict wcs, const char **restrict src, size_t n, size_t wn, mbstate_t *restrict st, size_t wcslen)
 {
 	if (wn > wcslen) a_crash();
-	return msbnrtowcs(wcs, src, n, wn, st);
+	return mbsnrtowcs(wcs, src, n, wn, st);
 }
 
 size_t __mbsrtowcs_chk(wchar_t *restrict ws, const char **restrict src, size_t wn, mbstate_t *restrict st, size_t wslen)
-- 
2.5.0