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.
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.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 24 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | mmc: davinci: avoid NULL deref of host->data in IRQ handler | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-24T16:04:49.056Z
Reserved: 2026-09-24T16:01:01.151Z
Link: CVE-2026-97502
No data.
Status : Received
Published: 2026-09-24T17:17:27.963
Modified: 2026-09-24T17:17:27.963
Link: CVE-2026-97502
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.