CVE-2024-26787 mmc: mmci: stm32: fix DMA API overlapping mappings warning
A bug in the Linux kernel MMC driver causes DMA mapping leaks and warnings when debug options are enabled, potentially leading to resource exhaustion.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-26787?
CVE-2024-26787 is a medium-severity vulnerability in Debian Debian Linux, published on 4 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mmc: mmci: stm32: fix DMA API overlapping mappings warning
Turning on CONFIG_DMA_API_DEBUG_SG results in the following warning:
DMA-API: mmci-pl18x 48220000.mmc: cacheline tracking EEXIST, overlapping mappings aren't supported WARNING: CPU: 1 PID: 51 at kernel/dma/debug.c:568 add_dma_entry+0x234/0x2f4 Modules linked in: CPU: 1 PID: 51 Comm: kworker/1:2 Not tainted 6.1.28 #1 Hardware name: STMicroelectronics STM32MP257F-EV1 Evaluation Board (DT) Workqueue: events_freezable mmc_rescan Call trace: add_dma_entry+0x234/0x2f4 debug_dma_map_sg+0x198/0x350 __dma_map_sg_attrs+0xa0/0x110 dma_map_sg_attrs+0x10/0x2c sdmmc_idma_prep_data+0x80/0xc0 mmci_prep_data+0x38/0x84 mmci_start_data+0x108/0x2dc mmci_request+0xe4/0x190 __mmc_start_request+0x68/0x140 mmc_start_request+0x94/0xc0 mmc_wait_for_req+0x70/0x100 mmc_send_tuning+0x108/0x1ac sdmmc_execute_tuning+0x14c/0x210 mmc_execute_tuning+0x48/0xec mmc_sd_init_uhs_card.part.0+0x208/0x464 mmc_sd_init_card+0x318/0x89c mmc_attach_sd+0xe4/0x180 mmc_rescan+0x244/0x320
DMA API debug brings to light leaking dma-mappings as dma_map_sg and dma_unmap_sg are not correctly balanced.
If an error occurs in mmci_cmd_irq function, only mmci_dma_error function is called and as this API is not managed on stm32 variant, dma_unmap_sg is never called in this error path.
Which versions are affected by CVE-2024-26787?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2024-26787?
Apply the vendor's patch.
Is CVE-2024-26787 being exploited?
There is no known exploitation of CVE-2024-26787 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as BELL-CVE-2024-26787, DEBIAN-CVE-2024-26787, GHSA-8vf4-q8g2-79g5, UBUNTU-CVE-2024-26787.