[git commit] sv,svc: fix NOEXEC fallout
Denys Vlasenko
vda.linux at googlemail.com
Sun Aug 6 19:23:03 UTC 2017
commit: https://git.busybox.net/busybox/commit/?id=b9be78070569e69960ba2b3c4098c3dc3316b9bd
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/master
function old new delta
svc_main 145 162 +17
sv 1280 1297 +17
status 139 133 -6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 34/-6) Total: 28 bytes
Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
console-tools/dumpkmap.c | 19 +++----------------
console-tools/resize.c | 2 ++
coreutils/cksum.c | 1 +
coreutils/date.c | 1 +
coreutils/stty.c | 1 +
runit/sv.c | 10 ++++++++--
util-linux/umount.c | 2 ++
7 files changed, 18 insertions(+), 18 deletions(-)
diff --git a/console-tools/dumpkmap.c b/console-tools/dumpkmap.c
index 5ffb0cd..b803e57 100644
--- a/console-tools/dumpkmap.c
+++ b/console-tools/dumpkmap.c
@@ -16,6 +16,7 @@
//config: stdout, in binary format. You can then use loadkmap to load it.
//applet:IF_DUMPKMAP(APPLET_NOEXEC(dumpkmap, dumpkmap, BB_DIR_BIN, BB_SUID_DROP, dumpkmap))
+/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
//kbuild:lib-$(CONFIG_DUMPKMAP) += dumpkmap.o
@@ -47,8 +48,6 @@ int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
{
struct kbentry ke;
int i, j, fd;
-#define flags bb_common_bufsiz1
- setup_common_bufsiz();
/* When user accidentally runs "dumpkmap FILE"
* instead of "dumpkmap >FILE", we'd dump binary stuff to tty.
@@ -60,19 +59,8 @@ int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
fd = get_console_fd_or_die();
-#if 0
- write(STDOUT_FILENO, "bkeymap", 7);
- /* Here we want to set everything to 0 except for indexes:
- * [0-2] [4-6] [8-10] [12]
- */
- /*memset(flags, 0x00, MAX_NR_KEYMAPS); - already is */
- memset(flags, 0x01, 13);
- flags[3] = flags[7] = flags[11] = 0;
- /* dump flags */
- write(STDOUT_FILENO, flags, MAX_NR_KEYMAPS);
-#define flags7 flags
-#else
- /* Same effect */
+#define flags bb_common_bufsiz1
+ setup_common_bufsiz();
/* 0 1 2 3 4 5 6 7 8 9 a b c=12 */
memcpy(flags, "bkeymap\1\1\1\0\1\1\1\0\1\1\1\0\1",
/* Can use sizeof, or sizeof-1. sizeof is even, using that */
@@ -80,7 +68,6 @@ int dumpkmap_main(int argc UNUSED_PARAM, char **argv)
);
write(STDOUT_FILENO, flags, 7 + MAX_NR_KEYMAPS);
#define flags7 (flags + 7)
-#endif
for (i = 0; i < 13; i++) {
if (flags7[i]) {
diff --git a/console-tools/resize.c b/console-tools/resize.c
index 9786667..8aa487c 100644
--- a/console-tools/resize.c
+++ b/console-tools/resize.c
@@ -24,6 +24,7 @@
//config: COLUMNS=80;LINES=44;export COLUMNS LINES;
//applet:IF_RESIZE(APPLET_NOEXEC(resize, resize, BB_DIR_USR_BIN, BB_SUID_DROP, resize))
+/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
//kbuild:lib-$(CONFIG_RESIZE) += resize.o
@@ -63,6 +64,7 @@ int resize_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
*/
tcgetattr(STDERR_FILENO, old_termios_p); /* fiddle echo */
+//TODO: die if the above fails?
memcpy(&new, old_termios_p, sizeof(new));
new.c_cflag |= (CLOCAL | CREAD);
new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
diff --git a/coreutils/cksum.c b/coreutils/cksum.c
index c0cf65d..059a333 100644
--- a/coreutils/cksum.c
+++ b/coreutils/cksum.c
@@ -13,6 +13,7 @@
//config: cksum is used to calculate the CRC32 checksum of a file.
//applet:IF_CKSUM(APPLET_NOEXEC(cksum, cksum, BB_DIR_USR_BIN, BB_SUID_DROP, cksum))
+/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
//kbuild:lib-$(CONFIG_CKSUM) += cksum.o
diff --git a/coreutils/date.c b/coreutils/date.c
index 89b2816..5a4ad5f 100644
--- a/coreutils/date.c
+++ b/coreutils/date.c
@@ -59,6 +59,7 @@
//config: MMDDhhmm[[YY]YY][.ss] format.
//applet:IF_DATE(APPLET_NOEXEC(date, date, BB_DIR_BIN, BB_SUID_DROP, date))
+/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */
//kbuild:lib-$(CONFIG_DATE) += date.o
diff --git a/coreutils/stty.c b/coreutils/stty.c
index 2292fa5..57e2cc3 100644
--- a/coreutils/stty.c
+++ b/coreutils/stty.c
@@ -785,6 +785,7 @@ struct globals {
} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
#define INIT_G() do { \
+ setup_common_bufsiz(); \
G.device_name = bb_msg_standard_input; \
G.max_col = 80; \
G.current_col = 0; /* we are noexec, must clear */ \
diff --git a/runit/sv.c b/runit/sv.c
index 0817ab4..630f1f3 100644
--- a/runit/sv.c
+++ b/runit/sv.c
@@ -193,7 +193,7 @@ struct globals {
/* "Bernstein" time format: unix + 0x400000000000000aULL */
uint64_t tstart, tnow;
svstatus_t svstatus;
- unsigned islog;
+ smallint islog;
} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
#define acts (G.acts )
@@ -203,7 +203,13 @@ struct globals {
#define tnow (G.tnow )
#define svstatus (G.svstatus )
#define islog (G.islog )
-#define INIT_G() do { setup_common_bufsiz(); } while (0)
+#define INIT_G() do { \
+ setup_common_bufsiz(); \
+ /* need to zero out, we are NOEXEC */ \
+ rc = EXIT_SUCCESS; \
+ islog = 0; \
+ /* other fields need not be zero */ \
+} while (0)
#define str_equal(s,t) (strcmp((s), (t)) == 0)
diff --git a/util-linux/umount.c b/util-linux/umount.c
index 33667b1..a6405df 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -35,6 +35,8 @@
* In this case, you might be actually happy if your standalone bbox shell
* does not fork+exec, but only forks and calls umount_main() which it already has!
* Let's go with NOEXEC.
+ *
+ * bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed.
*/
//kbuild:lib-$(CONFIG_UMOUNT) += umount.o
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