X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=lttng-syscalls.c;h=a4a8ed44cd9c76dbc38d0ce8e319182b9f52392e;hb=72a527538699ab5c72bfb0080a975f04209328b9;hp=cba0016007d95c190fc4a4987c0f727e8a7cefeb;hpb=d42918696623476bb957eae99718e10f7959b320;p=lttng-modules.git

diff --git a/lttng-syscalls.c b/lttng-syscalls.c
index cba00160..a4a8ed44 100644
--- a/lttng-syscalls.c
+++ b/lttng-syscalls.c
@@ -91,6 +91,7 @@ struct mmap_arg_struct;
 #define PARAMS(args...)	args
 
 /* Handle unknown syscalls */
+#undef TRACE_SYSTEM
 #define TRACE_SYSTEM syscalls_unknown
 #include "instrumentation/syscalls/headers/syscalls_unknown.h"
 #undef TRACE_SYSTEM
@@ -1036,6 +1037,8 @@ 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 +1051,14 @@ 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);
@@ -1060,18 +1071,18 @@ int lttng_syscall_filter_disable(struct lttng_channel *chan,
 		goto error;
 	}
 	if (syscall_nr >= 0) {
-		if (!test_bit(syscall_nr, chan->sc_filter->sc)) {
+		if (!test_bit(syscall_nr, filter->sc)) {
 			ret = -EEXIST;
 			goto error;
 		}
-		bitmap_clear(chan->sc_filter->sc, syscall_nr, 1);
+		bitmap_clear(filter->sc, syscall_nr, 1);
 	}
 	if (compat_syscall_nr >= 0) {
-		if (!test_bit(compat_syscall_nr, chan->sc_filter->sc_compat)) {
+		if (!test_bit(compat_syscall_nr, filter->sc_compat)) {
 			ret = -EEXIST;
 			goto error;
 		}
-		bitmap_clear(chan->sc_filter->sc_compat, compat_syscall_nr, 1);
+		bitmap_clear(filter->sc_compat, compat_syscall_nr, 1);
 	}
 apply_filter:
 	if (!chan->sc_filter)
@@ -1220,12 +1231,12 @@ 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;