Commit Graph

4 Commits

Author SHA1 Message Date
Paolo Bonzini 4bfb024bc7 memory: clamp cached translation in case it points to an MMIO region
In using the address_space_translate_internal API, address_space_cache_init
forgot one piece of advice that can be found in the code for
address_space_translate_internal:

    /* MMIO registers can be expected to perform full-width accesses based only
     * on their address, without considering adjacent registers that could
     * decode to completely different MemoryRegions.  When such registers
     * exist (e.g. I/O ports 0xcf8 and 0xcf9 on most PC chipsets), MMIO
     * regions overlap wildly.  For this reason we cannot clamp the accesses
     * here.
     *
     * If the length is small (as is the case for address_space_ldl/stl),
     * everything works fine.  If the incoming length is large, however,
     * the caller really has to do the clamping through memory_access_size.
     */

address_space_cache_init is exactly one such case where "the incoming length
is large", therefore we need to clamp the resulting length---not to
memory_access_size though, since we are not doing an access yet, but to
the size of the resulting section.  This ensures that subsequent accesses
to the cached MemoryRegionSection will be in range.

With this patch, the enclosed testcase notices that the used ring does
not fit into the MSI-X table and prints a "qemu-system-x86_64: Cannot map used"
error.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:52:00 -05:00
Philippe Mathieu-Daudé 6536c9e0eb tests/qtest/fuzz-test: Quit test_lp1878642 once done
Missed in fd25017284 ("qtest: add a reproducer for LP#1878642").

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201201191026.4149955-2-philmd@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-12-09 08:04:34 +01:00
Alexander Bulekov fd25017284 qtest: add a reproducer for LP#1878642
https://bugs.launchpad.net/qemu/+bug/1878642

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20201102163336.115444-1-alxndr@bu.edu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-03 09:42:53 -05:00
Li Qiang d8dd109501 qtest: add fuzz test case
Currently the device fuzzer finds more and more issues.
For every fuzz case, we need not only the fixes but also
the corresponding test case. We can analysis the reproducer
for every case and find what happened in where and write
a beautiful test case. However the raw data of reproducer is not
friendly to analysis. It will take a very long time, even far more
than the fixes itself. So let's create a new file to hold all of
the fuzz test cases and just use the raw data to act as the test
case. This way nobody will be afraid of writing a test case for
the fuzz reproducer.

This patch adds the issue LP#1878263 test case.

Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20200921160605.19329-1-liq3ea@163.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
[thuth: Slightly adjusted commit message, removed empty lines]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-13 08:08:55 +02:00