Hi, As presented in [1] there is a bug in the zone code in raw_co_prw(), specifically we don’t check whether there actually is zone information before running code that assumes there is (and thus we run into a division by zero). This has now also been reported in [2].
I believe the solution [1] is incomplete, though, which is why I’m sending this separate series: I don’t think checking bs->wps and/or bs->bl.zone_size to determine whether there is zone information is right; for example, we do not have raw_refresh_zoned_limits() clear those values if on a refresh, zone information were to disappear. It is also weird that we separate checking bs->wps and bs->bl.zone_size at all; raw_refresh_zoned_limits() seems to intend to ensure that either we have information with non-NULL bs->wps and non-zero bs->bl.zone_size, or we don’t. I think we should have a single flag that tells whether we have valid information or not, and it looks to me like bs->bl.zoned != BLK_Z_NONE is the condition that fits best. Patch 1 ensures that raw_refresh_zoned_limits() will set bs->bl.zoned to BLK_Z_NONE on error, so that we can actually be sure that this condition tells us whether we have valid information or not. Patch 2 unifies all conditional checks for zone information to use bs->bl.zoned != BLK_Z_NONE. Patch 3 is the I/O error path fix, which is not really different from [1]. Patch 4 does a bit of clean-up. Patch 5 adds a regression test. [1] https://lists.nongnu.org/archive/html/qemu-devel/2023-06/msg01742.html [2] https://bugzilla.redhat.com/show_bug.cgi?id=2234374 Hanna Czenczek (5): file-posix: Clear bs->bl.zoned on error file-posix: Check bs->bl.zoned for zone info file-posix: Fix zone update in I/O error path file-posix: Simplify raw_co_prw's 'out' zone code tests/file-io-error: New test block/file-posix.c | 42 +++++---- tests/qemu-iotests/tests/file-io-error | 99 ++++++++++++++++++++++ tests/qemu-iotests/tests/file-io-error.out | 31 +++++++ 3 files changed, 150 insertions(+), 22 deletions(-) create mode 100755 tests/qemu-iotests/tests/file-io-error create mode 100644 tests/qemu-iotests/tests/file-io-error.out -- 2.41.0
