Description
In the Linux kernel, the following vulnerability has been resolved: mmc: davinci: avoid NULL deref of host->data in IRQ handler mmc_davinci_irq() returns early only when both host->cmd and host->data are NULL: if (host->cmd == NULL && host->data == NULL) { ... return IRQ_NONE; } So we may legitimately reach the rest of the handler with host->data == NULL (and therefore data == NULL). The DATDNE branch already guards against this with an explicit "if (data != NULL)" check, but the subsequent TOUTRD ("read data timeout") and CRCWR/CRCRD ("data CRC error") branches dereference data unconditionally: if (qstatus & MMCST0_TOUTRD) { data->error = -ETIMEDOUT; <-- NULL deref ... davinci_abort_data(host, data); } if (qstatus & (MMCST0_CRCWR | MMCST0_CRCRD)) { data->error = -EILSEQ; <-- NULL deref ... } If either bit is set in qstatus while host->data is NULL, the kernel will crash inside the IRQ handler. smatch flags this: drivers/mmc/host/davinci_mmc.c:933 mmc_davinci_irq() error: we previously assumed 'data' could be null (see line 914) Gate both branches on a non-NULL data, matching the existing pattern used by the DATDNE branch. No functional change for callers where data is non-NULL, which is the only case in which these branches did meaningful work before this change.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
b4cff4549b7a8c5fc8b88e3493b6287555f0512c to < 51738de7dd5f8e8b33dfc07ef85bc06d3bf41e96affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < f216cf00e829895ff49bdf695c944915e59bd698affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < a0cde8d70d64c1a75fbd57f01d9f2d7cccac8319affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < 3c5e3e5badbf0592332887d12db02458323682c3affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < a01cedf230dc0fcd55b994f5e548d3982ba4c732affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < 5b7e151fe9ea9311ba601849aaecdc4fc97fd577affectedb4cff4549b7a8c5fc8b88e3493b6287555f0512c to < 4f28846aaf8db9668e338b8987973f8935edff34affected
Linux Linux
Default version status: affected
2.6.33affected0 to < 2.6.33unaffected5.10.271 to ≤ 5.10.*unaffected5.15.222 to ≤ 5.15.*unaffected6.1.189 to ≤ 6.1.*unaffected6.6.158 to ≤ 6.6.*unaffected6.12.111 to ≤ 6.12.*unaffected6.18.53 to ≤ 6.18.*unaffected7.2 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/51738de7dd5f8e8b33dfc07ef85bc06d3bf41e96 ↗
- https://git.kernel.org/stable/c/f216cf00e829895ff49bdf695c944915e59bd698 ↗
- https://git.kernel.org/stable/c/a0cde8d70d64c1a75fbd57f01d9f2d7cccac8319 ↗
- https://git.kernel.org/stable/c/3c5e3e5badbf0592332887d12db02458323682c3 ↗
- https://git.kernel.org/stable/c/a01cedf230dc0fcd55b994f5e548d3982ba4c732 ↗
- https://git.kernel.org/stable/c/5b7e151fe9ea9311ba601849aaecdc4fc97fd577 ↗
- https://git.kernel.org/stable/c/4f28846aaf8db9668e338b8987973f8935edff34 ↗