Bug 2424988 (CVE-2023-54020)
| Summary: | CVE-2023-54020 kernel: dmaengine: sf-pdma: pdma_desc memory leak fix | ||
|---|---|---|---|
| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security DevOps Team <prodsec-dev> |
| Status: | NEW --- | QA Contact: | |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | unspecified | CC: | rhel-process-autobot, watson-tool-maintainers |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
In the Linux kernel, the following vulnerability has been resolved: dmaengine: sf-pdma: pdma_desc memory leak fix Commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel") changed sf_pdma_prep_dma_memcpy() to unconditionally allocate a new sf_pdma_desc each time it is called. The driver previously recycled descs, by checking the in_use flag, only allocating additional descs if the existing one was in use. This logic was removed in commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel"), but sf_pdma_free_desc() was not changed to handle the new behaviour. As a result, each time sf_pdma_prep_dma_memcpy() is called, the previous descriptor is leaked, over time leading to memory starvation: unreferenced object 0xffffffe008447300 (size 192): comm "irq/39-mchp_dsc", pid 343, jiffies 4294906910 (age 981.200s) hex dump (first 32 bytes): 00 00 00 ff 00 00 00 00 b8 c1 00 00 00 00 00 00 ................ 00 00 70 08 10 00 00 00 00 00 00 c0 00 00 00 00 ..p............. backtrace: [<00000000064a04f4>] kmemleak_alloc+0x1e/0x28 [<00000000018927a7>] kmem_cache_alloc+0x11e/0x178 [<000000002aea8d16>] sf_pdma_prep_dma_memcpy+0x40/0x112 Add the missing kfree() to sf_pdma_free_desc(), and remove the redundant in_use flag.