aboutsummaryrefslogtreecommitdiff
path: root/miscutils
diff options
context:
space:
mode:
Diffstat (limited to 'miscutils')
-rw-r--r--miscutils/Config.src7
-rw-r--r--miscutils/Kbuild.src1
-rw-r--r--miscutils/wall.c25
3 files changed, 24 insertions, 9 deletions
diff --git a/miscutils/Config.src b/miscutils/Config.src
index b9fc196d8..117ec7739 100644
--- a/miscutils/Config.src
+++ b/miscutils/Config.src
@@ -591,13 +591,6 @@ config VOLNAME
help
Prints a CD-ROM volume name.
-config WALL
- bool "wall"
- default y
- depends on FEATURE_UTMP
- help
- Write a message to all users that are logged in.
-
config WATCHDOG
bool "watchdog"
default y
diff --git a/miscutils/Kbuild.src b/miscutils/Kbuild.src
index 8c498643b..f3954f407 100644
--- a/miscutils/Kbuild.src
+++ b/miscutils/Kbuild.src
@@ -46,5 +46,4 @@ lib-$(CONFIG_TIME) += time.o
lib-$(CONFIG_TIMEOUT) += timeout.o
lib-$(CONFIG_TTYSIZE) += ttysize.o
lib-$(CONFIG_VOLNAME) += volname.o
-lib-$(CONFIG_WALL) += wall.o
lib-$(CONFIG_WATCHDOG) += watchdog.o
diff --git a/miscutils/wall.c b/miscutils/wall.c
index 762f53b72..c74f4f27b 100644
--- a/miscutils/wall.c
+++ b/miscutils/wall.c
@@ -6,6 +6,18 @@
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//config:config WALL
+//config: bool "wall"
+//config: default y
+//config: depends on FEATURE_UTMP
+//config: help
+//config: Write a message to all users that are logged in.
+
+/* Needs to be run by root or be suid root - needs to write to /dev/TTY: */
+//applet:IF_WALL(APPLET(wall, BB_DIR_USR_BIN, BB_SUID_REQUIRE))
+
+//kbuild:lib-$(CONFIG_WALL) += wall.o
+
//usage:#define wall_trivial_usage
//usage: "[FILE]"
//usage:#define wall_full_usage "\n\n"
@@ -22,8 +34,19 @@ int wall_main(int argc UNUSED_PARAM, char **argv)
{
struct utmp *ut;
char *msg;
- int fd = argv[1] ? xopen(argv[1], O_RDONLY) : STDIN_FILENO;
+ int fd;
+ fd = STDIN_FILENO;
+ if (argv[1]) {
+ /* The applet is setuid.
+ * Access to the file must be under user's uid/gid.
+ */
+ setfsuid(getuid());
+ setfsgid(getgid());
+ fd = xopen(argv[1], O_RDONLY);
+ setfsuid(geteuid());
+ setfsgid(getegid());
+ }
msg = xmalloc_read(fd, NULL);
if (ENABLE_FEATURE_CLEAN_UP && argv[1])
close(fd);