CVE-2026-97502

About vulnerability

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 product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

linux @ 5.4.0 (+17 more)

Live-patch status from KernelCare for each operating system.