An out-of-bounds r/w access issue was found in the SDHCI Controller emulator of QEMU. It may occur while doing multi block SDMA, if transfer block size exceeds the 's->fifo_buffer[s->buf_maxsz]' size. It'd leave the current element pointer 's->data_count' pointing out of bounds. Leading the subsequent DMA r/w operation to OOB access issue. A guest user/process may use this flaw to crash the QEMU process resulting in DoS scenario. Upstream patches: ----------------- -> https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg00733.html -> https://lists.nongnu.org/archive/html/qemu-devel/2020-09/msg01439.html Reference: ---------- -> https://www.openwall.com/lists/oss-security/2020/09/16/6
Acknowledgments: Name: Sergej Schumilo (Ruhr-University Bochum), Cornelius Aschermann (Ruhr-University Bochum), Simon Wrner (Ruhr-University Bochum)
External References: https://bugs.launchpad.net/qemu/+bug/1892960 https://ruhr-uni-bochum.sciebo.de/s/NNWP2GfwzYKeKwE?path=%2Fsdhci_oob_write1
Created qemu tracking bugs for this issue: Affects: fedora-all [bug 1879673]
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2020-25085