From d13e3b46700a58da5ea2a098003cd2ddaf0a3f76 Mon Sep 17 00:00:00 2001 From: Zhao Liu Date: Mon, 11 Mar 2024 11:38:01 +0800 Subject: block/qcow2: Fix missing ERRP_GUARD() for error_prepend() As the comment in qapi/error, passing @errp to error_prepend() requires ERRP_GUARD(): * = Why, when and how to use ERRP_GUARD() = * * Without ERRP_GUARD(), use of the @errp parameter is restricted: ... * - It should not be passed to error_prepend(), error_vprepend() or * error_append_hint(), because that doesn't work with &error_fatal. * ERRP_GUARD() lifts these restrictions. * * To use ERRP_GUARD(), add it right at the beginning of the function. * @errp can then be used without worrying about the argument being * NULL or &error_fatal. ERRP_GUARD() could avoid the case when @errp is &error_fatal, the user can't see this additional information, because exit() happens in error_setg earlier than information is added [1]. In block/qcow2.c, there are 2 functions passing @errp to error_prepend() without ERRP_GUARD(): - qcow2_co_create() - qcow2_co_truncate() There are too many possible callers to check the impact of the defect; it may or may not be harmless. Thus it is necessary to protect @errp with ERRP_GUARD(). Therefore, to avoid the issue like [1] said, add missing ERRP_GUARD() at their beginning. [1]: Issue description in the commit message of commit ae7c80a7bd73 ("error: New macro ERRP_GUARD()"). Cc: Kevin Wolf Cc: Hanna Reitz Cc: qemu-block@nongnu.org Signed-off-by: Zhao Liu Reviewed-by: Eric Blake Message-ID: <20240311033822.3142585-9-zhao1.liu@linux.intel.com> Signed-off-by: Thomas Huth --- block/qcow2.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'block') diff --git a/block/qcow2.c b/block/qcow2.c index 204f5854cf..956128b409 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3483,6 +3483,7 @@ static uint64_t qcow2_opt_get_refcount_bits_del(QemuOpts *opts, int version, static int coroutine_fn GRAPH_UNLOCKED qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp) { + ERRP_GUARD(); BlockdevCreateOptionsQcow2 *qcow2_opts; QDict *options; @@ -4283,6 +4284,7 @@ static int coroutine_fn GRAPH_RDLOCK qcow2_co_truncate(BlockDriverState *bs, int64_t offset, bool exact, PreallocMode prealloc, BdrvRequestFlags flags, Error **errp) { + ERRP_GUARD(); BDRVQcow2State *s = bs->opaque; uint64_t old_length; int64_t new_l1_size; -- cgit v1.2.3