X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=lttng-syscalls.c;h=846946ad374ca00d7af1b4f3c36fa0d60155938d;hb=24875133a4330acb17b33bc9b3a57e59e73022a6;hp=1489934f3319bbad05de08d3c404f155bd2feac7;hpb=cecef7f86625593d7e26337294ceda7252557f59;p=lttng-modules.git

diff --git a/lttng-syscalls.c b/lttng-syscalls.c
index 1489934f..846946ad 100644
--- a/lttng-syscalls.c
+++ b/lttng-syscalls.c
@@ -1036,6 +1036,8 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan,
 	WARN_ON_ONCE(!chan->sc_table);
 
 	if (!chan->sc_filter) {
+		if (!chan->syscall_all)
+			return -EEXIST;
 		filter = kzalloc(sizeof(struct lttng_syscall_filter),
 				GFP_KERNEL);
 		if (!filter)
@@ -1048,6 +1050,14 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan,
 	}
 
 	if (!name) {
+		/* Fail if all syscalls are already disabled. */
+		if (bitmap_empty(filter->sc, NR_syscalls)
+			&& bitmap_empty(filter->sc_compat,
+				NR_compat_syscalls)) {
+			ret = -EEXIST;
+			goto error;
+		}
+
 		/* Disable all system calls */
 		bitmap_clear(filter->sc, 0, NR_syscalls);
 		bitmap_clear(filter->sc_compat, 0, NR_compat_syscalls);
@@ -1220,12 +1230,12 @@ long lttng_channel_syscall_mask(struct lttng_channel *channel,
 
 	for (bit = 0; bit < ARRAY_SIZE(sc_table); bit++) {
 		bt_bitfield_write_be(tmp_mask, char, bit, 1,
-			test_bit(bit, filter->sc));
+			filter ? test_bit(bit, filter->sc) : 1);
 	}
 	for (; bit < sc_tables_len; bit++) {
 		bt_bitfield_write_be(tmp_mask, char, bit, 1,
-			test_bit(bit - ARRAY_SIZE(sc_table),
-				filter->sc_compat));
+			filter ? test_bit(bit - ARRAY_SIZE(sc_table),
+				filter->sc_compat) : 1);
 	}
 	if (copy_to_user(usyscall_mask->mask, tmp_mask, bitmask_len))
 		ret = -EFAULT;