libmemif: fix insecure uses of strncpy
A calling patterm of "strncpy(dst, src, strlen(src))" invites a lot of troubles.
However, even using the target size may result in a problem if the string is
longer, since then the termination is not done.
Use strlcpy(dst, src, sizeof(dst)), which will always null-terminate
the string.
Change-Id: I8ddaf3dc8380a78af08914e81849279dae7ab24a
Type: fix
Signed-off-by: Andrew Yourtchenko <ayourtch@gmail.com>
Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
diff --git a/extras/libmemif/src/CMakeLists.txt b/extras/libmemif/src/CMakeLists.txt
index aced550..ddb8a52 100644
--- a/extras/libmemif/src/CMakeLists.txt
+++ b/extras/libmemif/src/CMakeLists.txt
@@ -34,6 +34,13 @@
add_library(memif SHARED ${MEMIF_SOURCES})
target_link_libraries(memif ${CMAKE_THREAD_LIBS_INIT})
+
+find_library(LIB_BSD bsd)
+if(LIB_BSD)
+ add_compile_definitions(HAS_LIB_BSD)
+ target_link_libraries(memif ${LIB_BSD})
+endif()
+
foreach(file ${MEMIF_HEADERS})
get_filename_component(dir ${file} DIRECTORY)
install(
diff --git a/extras/libmemif/src/main.c b/extras/libmemif/src/main.c
index d7345d6..1eb6929 100644
--- a/extras/libmemif/src/main.c
+++ b/extras/libmemif/src/main.c
@@ -158,14 +158,11 @@
{
if (err_code >= ERRLIST_LEN)
{
- strncpy (memif_buf, MEMIF_ERR_UNDEFINED, strlen (MEMIF_ERR_UNDEFINED));
- memif_buf[strlen (MEMIF_ERR_UNDEFINED)] = '\0';
+ strlcpy (memif_buf, MEMIF_ERR_UNDEFINED, sizeof (memif_buf));
}
else
{
- strncpy (memif_buf, memif_errlist[err_code],
- strlen (memif_errlist[err_code]));
- memif_buf[strlen (memif_errlist[err_code])] = '\0';
+ strlcpy (memif_buf, memif_errlist[err_code], sizeof (memif_buf));
}
return memif_buf;
}
@@ -532,14 +529,12 @@
if (app_name != NULL)
{
- uint8_t len = (strlen (app_name) > MEMIF_NAME_LEN)
- ? strlen (app_name) : MEMIF_NAME_LEN;
- strncpy ((char *) lm->app_name, app_name, len);
+ strlcpy ((char *) lm->app_name, app_name, sizeof (lm->app_name));
}
else
{
- strncpy ((char *) lm->app_name, MEMIF_DEFAULT_APP_NAME,
- strlen (MEMIF_DEFAULT_APP_NAME));
+ strlcpy ((char *) lm->app_name, MEMIF_DEFAULT_APP_NAME,
+ sizeof (lm->app_name));
}
lm->poll_cancel_fd = -1;
@@ -699,14 +694,12 @@
/* set app name */
if (app_name != NULL)
{
- uint8_t len = (strlen (app_name) > MEMIF_NAME_LEN)
- ? strlen (app_name) : MEMIF_NAME_LEN;
- strncpy ((char *) lm->app_name, app_name, len);
+ strlcpy ((char *) lm->app_name, app_name, MEMIF_NAME_LEN);
}
else
{
- strncpy ((char *) lm->app_name, MEMIF_DEFAULT_APP_NAME,
- strlen (MEMIF_DEFAULT_APP_NAME));
+ strlcpy ((char *) lm->app_name, MEMIF_DEFAULT_APP_NAME,
+ sizeof (lm->app_name));
}
lm->poll_cancel_fd = -1;
@@ -885,8 +878,7 @@
DBG ("socket %d created", ms->fd);
un.sun_family = AF_UNIX;
- strncpy ((char *) un.sun_path, (char *) ms->filename,
- sizeof (un.sun_path) - 1);
+ strlcpy ((char *) un.sun_path, (char *) ms->filename, sizeof (un.sun_path));
if (setsockopt (ms->fd, SOL_SOCKET, SO_PASSCRED, &on, sizeof (on)) < 0)
{
err = memif_syscall_error_handler (errno);
@@ -963,7 +955,7 @@
goto error;
}
memset (ms->filename, 0, strlen (filename) + sizeof (char));
- strncpy ((char *) ms->filename, filename, strlen (filename));
+ strlcpy ((char *) ms->filename, filename, sizeof (ms->filename));
ms->type = MEMIF_SOCKET_TYPE_NONE;
@@ -1047,7 +1039,7 @@
goto error;
}
memset (ms->filename, 0, strlen (filename) + sizeof (char));
- strncpy ((char *) ms->filename, filename, strlen (filename));
+ strlcpy ((char *) ms->filename, filename, sizeof (ms->filename));
ms->type = MEMIF_SOCKET_TYPE_NONE;
@@ -1150,12 +1142,12 @@
conn->private_ctx = private_ctx;
memset (&conn->run_args, 0, sizeof (memif_conn_run_args_t));
- uint8_t l = strlen ((char *) args->interface_name);
- strncpy ((char *) conn->args.interface_name, (char *) args->interface_name,
- l);
+ strlcpy ((char *) conn->args.interface_name, (char *) args->interface_name,
+ sizeof (conn->args.interface_name));
- if ((l = strlen ((char *) args->secret)) > 0)
- strncpy ((char *) conn->args.secret, (char *) args->secret, l);
+ if ((strlen ((char *) args->secret)) > 0)
+ strlcpy ((char *) conn->args.secret, (char *) args->secret,
+ sizeof (conn->args.secret));
if (args->socket != NULL)
conn->args.socket = args->socket;
@@ -1260,7 +1252,7 @@
sun.sun_family = AF_UNIX;
- strncpy (sun.sun_path, (char *) ms->filename, sizeof (sun.sun_path) - 1);
+ strlcpy (sun.sun_path, (char *) ms->filename, sizeof (sun.sun_path));
if (connect (sockfd, (struct sockaddr *) &sun,
sizeof (struct sockaddr_un)) == 0)
diff --git a/extras/libmemif/src/memif_private.h b/extras/libmemif/src/memif_private.h
index dd58d62..59899fd 100644
--- a/extras/libmemif/src/memif_private.h
+++ b/extras/libmemif/src/memif_private.h
@@ -66,6 +66,33 @@
#define DBG(...)
#endif /* MEMIF_DBG */
+#ifndef HAS_LIB_BSD
+static inline size_t
+strlcpy (char *dest, const char *src, size_t len)
+{
+ const char *s = src;
+ size_t n = len;
+
+ while (--n > 0)
+ {
+ if ((*dest++ = *s++) == '\0')
+ break;
+ }
+
+ if (n == 0)
+ {
+ if (len != 0)
+ *dest = '\0';
+ while (*s++)
+ ;
+ }
+
+ return (s - src - 1);
+}
+#else
+#include <bsd/string.h>
+#endif
+
typedef enum
{
MEMIF_SOCKET_TYPE_NONE = 0, /* unassigned, not used by any interface */
diff --git a/extras/libmemif/src/socket.c b/extras/libmemif/src/socket.c
index 2454616..b801cac 100644
--- a/extras/libmemif/src/socket.c
+++ b/extras/libmemif/src/socket.c
@@ -111,8 +111,7 @@
h->max_region = MEMIF_MAX_REGION;
h->max_log2_ring_size = MEMIF_MAX_LOG2_RING_SIZE;
- strncpy ((char *) h->name, (char *) lm->app_name,
- strlen ((char *) lm->app_name));
+ strlcpy ((char *) h->name, (char *) lm->app_name, sizeof (h->name));
/* msg hello is not enqueued but sent directly,
because it is the first msg to be sent */
@@ -139,8 +138,7 @@
i->id = c->args.interface_id;
i->mode = c->args.mode;
- strncpy ((char *) i->name, (char *) lm->app_name,
- strlen ((char *) lm->app_name));
+ strlcpy ((char *) i->name, (char *) lm->app_name, sizeof (i->name));
if (strlen ((char *) c->args.secret) > 0)
strncpy ((char *) i->secret, (char *) c->args.secret, sizeof (i->secret));
@@ -260,8 +258,8 @@
e->msg.type = MEMIF_MSG_TYPE_CONNECT;
e->fd = -1;
- strncpy ((char *) cm->if_name, (char *) c->args.interface_name,
- strlen ((char *) c->args.interface_name));
+ strlcpy ((char *) cm->if_name, (char *) c->args.interface_name,
+ sizeof (cm->if_name));
e->next = NULL;
if (c->msg_queue == NULL)
@@ -295,8 +293,8 @@
e->msg.type = MEMIF_MSG_TYPE_CONNECTED;
e->fd = -1;
- strncpy ((char *) cm->if_name, (char *) c->args.interface_name,
- strlen ((char *) c->args.interface_name));
+ strlcpy ((char *) cm->if_name, (char *) c->args.interface_name,
+ sizeof (cm->if_name));
e->next = NULL;
if (c->msg_queue == NULL)
@@ -327,12 +325,12 @@
msg.type = MEMIF_MSG_TYPE_DISCONNECT;
d->code = err_code;
uint16_t l = strlen ((char *) err_string);
- if (l > 96)
+ if (l > sizeof (d->string) - 1)
{
- DBG ("Disconnect string too long. Sending first 96 characters.");
- l = 96;
+ DBG ("Disconnect string too long. Sending the first %d characters.",
+ sizeof (d->string) - 1);
}
- strncpy ((char *) d->string, (char *) err_string, l);
+ strlcpy ((char *) d->string, (char *) err_string, sizeof (d->string));
return memif_msg_send (fd, &msg, -1);
}
@@ -356,8 +354,7 @@
c->run_args.log2_ring_size = memif_min (h->max_log2_ring_size,
c->args.log2_ring_size);
c->run_args.buffer_size = c->args.buffer_size;
- strncpy ((char *) c->remote_name, (char *) h->name,
- strlen ((char *) h->name));
+ strlcpy ((char *) c->remote_name, (char *) h->name, sizeof (c->remote_name));
return MEMIF_ERR_SUCCESS; /* 0 */
}
@@ -420,8 +417,7 @@
goto error;
}
- strncpy ((char *) c->remote_name, (char *) i->name,
- strlen ((char *) i->name));
+ strlcpy ((char *) c->remote_name, (char *) i->name, sizeof (c->remote_name));
if (strlen ((char *) c->args.secret) > 0)
{
@@ -588,8 +584,8 @@
if (err != MEMIF_ERR_SUCCESS)
return err;
- strncpy ((char *) c->remote_if_name, (char *) cm->if_name,
- strlen ((char *) cm->if_name));
+ strlcpy ((char *) c->remote_if_name, (char *) cm->if_name,
+ sizeof (c->remote_if_name));
int i;
if (c->on_interrupt != NULL)
@@ -625,7 +621,7 @@
return err;
strncpy ((char *) c->remote_if_name, (char *) cm->if_name,
- strlen ((char *) cm->if_name));
+ sizeof (c->remote_if_name));
int i;
if (c->on_interrupt != NULL)
@@ -650,7 +646,7 @@
memset (c->remote_disconnect_string, 0,
sizeof (c->remote_disconnect_string));
strncpy ((char *) c->remote_disconnect_string, (char *) d->string,
- strlen ((char *) d->string));
+ sizeof (c->remote_disconnect_string));
/* on returning error, handle function will call memif_disconnect () */
DBG ("disconnect received: %s, mode: %d",