Linux vulnerability

What happened

In the Linux kernel, the following vulnerability has been resolved: mmc: via-sdmmc: stop card-detect handling on probe failure request_irq() registers the SD card-detect interrupt and the probe enables it before mmc_add_host() runs. If mmc_add_host() fails, the error path only unmaps the registers and returns: the interrupt stays registered, so the handler keeps running against the host once it is freed. via_sdc_isr() dereferences sdhost and its MMIO base and schedules carddet_work, which via_sdc_card_detect() also runs against freed memory through its container_of() dereference. Add a probe-error path that disables and frees the interrupt and cancels carddet_work before unmapping. carddet_work can re-enable the device interrupt via via_reset_pcictrl(), which restores PCIINTCTRL, so mask it again after cancelling the work. This issue was found by an in-house static analysis tool and confirmed by manual code review.

Affected versions

Linux: e4e46fb61e3bb4628170810d3f2b996b709b90d9 through before efe7f25dd27e35063477b4b0e7eed3675669fd99 (git); e4e46fb61e3bb4628170810d3f2b996b709b90d9 through before 2550f89589caad7402d618d7dffc038582c94b6b (git); e4e46fb61e3bb4628170810d3f2b996b709b90d9 through before c2b8a624911999399cc14822fec3e35032b3cee4 (git); e4e46fb61e3bb4628170810d3f2b996b709b90d9 through before 088eaa92fcebaa6b957ccf9635afdf39643a577d (git); 076bcd2c93e16b05c10564e299d6e5d26a766d00 (git); 12b8e81b77c05c658efd9cde3585bbd65ae39b59 (git); 95025a8dd0ec015872f6c16473fe04d6264e68ca (git); f59ef2a47a228e51322ad76752a55a8917c56e38 (git); 63400da6cd37a9793c19bb6aed7131b58b975a04 (git); 0959cc1685eb19774300d43ef25e318b457b156b (git); 0ec94795114edc7e24ec71849dce42bfa61dafa3 (git); ba91b413983a9235792523c6b9f7ba2586c4d75d (git); 4.9.337 through before 4.10 (semver); 4.14.303 through before 4.15 (semver); 4.19.270 through before 4.20 (semver); 5.4.229 through before 5.5 (semver); 5.10.163 through before 5.11 (semver); 5.15.86 through before 5.16 (semver); 6.0.16 through before 6.1 (semver); 6.1.2 through before 6.2 (semver); 6.2 Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

• Apply vendor-provided updates or mitigations.
• Review affected product exposure and access logs.