From: Hanna Reitz <hre...@redhat.com>
With CAP_DAC_OVERRIDE (which e.g. root generally has), permission checks
will be bypassed when opening files.
308 in one instance tries to open a read-only file (FUSE export) with
qemu-io as read/write, and expects this to fail. However, when running
it as root, opening will succeed (thanks to CAP_DAC_OVERRIDE) and only
the actual write operation will fail.
Note this as "Case not run", but have the test pass in either case.
Reported-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Fixes: 2c7dd057aa7bd7a875e9b1a53975c220d6380bc4
("export/fuse: Pass default_permissions for mount")
Signed-off-by: Hanna Reitz <hre...@redhat.com>
Message-Id: <20220103120014.13061-1-hre...@redhat.com>
Signed-off-by: Kevin Wolf <kw...@redhat.com>
---
tests/qemu-iotests/308 | 25 +++++++++++++++++++++++--
tests/qemu-iotests/308.out | 2 +-
2 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/tests/qemu-iotests/308 b/tests/qemu-iotests/308
index 2e3f8f4282..bde4aac2fa 100755
--- a/tests/qemu-iotests/308
+++ b/tests/qemu-iotests/308
@@ -230,8 +230,29 @@ echo '=== Writable export ==='
fuse_export_add 'export-mp' "'mountpoint': '$EXT_MP', 'writable': true"
# Check that writing to the read-only export fails
-$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$TEST_IMG" 2>&1 \
- | _filter_qemu_io | _filter_testdir | _filter_imgfmt
+output=$($QEMU_IO -f raw -c 'write -P 42 1M 64k' "$TEST_IMG" 2>&1 \
+ | _filter_qemu_io | _filter_testdir | _filter_imgfmt)
+
+# Expected reference output: Opening the file fails because it has no
+# write permission
+reference="Could not open 'TEST_DIR/t.IMGFMT': Permission denied"
+
+if echo "$output" | grep -q "$reference"; then
+ echo "Writing to read-only export failed: OK"
+elif echo "$output" | grep -q "write failed: Permission denied"; then
+ # With CAP_DAC_OVERRIDE (e.g. when running this test as root), the export
+ # can be opened regardless of its file permissions, but writing will then
+ # fail. This is not the result for which we want to test, so count this as
+ # a SKIP.
+ _casenotrun "Opening RO export as R/W succeeded, perhaps because of" \
+ "CAP_DAC_OVERRIDE"
+
+ # Still, write this to the reference output to make the test pass
+ echo "Writing to read-only export failed: OK"
+else
+ echo "Writing to read-only export failed: ERROR"
+ echo "$output"
+fi
# But here it should work
$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$EXT_MP" | _filter_qemu_io
diff --git a/tests/qemu-iotests/308.out b/tests/qemu-iotests/308.out
index fc47bb11a2..e4467a10cf 100644
--- a/tests/qemu-iotests/308.out
+++ b/tests/qemu-iotests/308.out
@@ -95,7 +95,7 @@ virtual size: 0 B (0 bytes)
'mountpoint': 'TEST_DIR/t.IMGFMT.fuse', 'writable': true
} }
{"return": {}}
-qemu-io: can't open device TEST_DIR/t.IMGFMT: Could not open
'TEST_DIR/t.IMGFMT': Permission denied
+Writing to read-only export failed: OK
wrote 65536/65536 bytes at offset 1048576
64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 65536/65536 bytes at offset 1048576
--
2.31.1
