{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/net/ethernet/stmicro/stmmac/stmmac_main.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "fdeb95b1fc7de25c9362990efb9996a8d761055c", "status": "affected", "version": "7414a28de1b3b028714859078c00a874f9feff52", "versionType": "git"}, {"lessThan": "e1c50b273298c7cd9b08b113e7a7598b531a02f5", "status": "affected", "version": "779334e59850f863bf34665e0ff0b6faf126873b", "versionType": "git"}, {"lessThan": "5c910f7708e3c507b037ca91ca5b09f8cfe71e65", "status": "affected", "version": "b6cb4541853c7ee512111b0e7ddf3cb66c99c137", "versionType": "git"}, {"lessThan": "4af2e62cbcda575a174acd230c3f3a208135e16d", "status": "affected", "version": "b6cb4541853c7ee512111b0e7ddf3cb66c99c137", "versionType": "git"}, {"lessThan": "950cb436165aad0f8f2cd49da3cd07677465bcde", "status": "affected", "version": "b6cb4541853c7ee512111b0e7ddf3cb66c99c137", "versionType": "git"}, {"lessThan": "0bb05e6adfa99a2ea1fee1125cc0953409f83ed8", "status": "affected", "version": "b6cb4541853c7ee512111b0e7ddf3cb66c99c137", "versionType": "git"}, {"status": "affected", "version": "b435b4573240b5530830a1a60e005c6fcfd928a0", "versionType": "git"}, {"lessThan": "6.1.176", "status": "affected", "version": "6.1.64", "versionType": "semver"}, {"lessThan": "6.6.140", "status": "affected", "version": "6.6.3", "versionType": "semver"}, {"lessThan": "6.6", "status": "affected", "version": "6.5.13", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/net/ethernet/stmicro/stmmac/stmmac_main.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.7"}, {"lessThan": "6.7", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.176", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.140", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.88", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.30", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.7", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"affectedData": [{"defaultStatus": "unknown", "product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7D2385BE-AA5B-4108-986E-94FE78869E0B", "versionEndExcluding": "6.1.176", "versionStartIncluding": "6.1.64", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "3B6AC16B-2F1C-4FDF-8F49-09FC11C3F5B0", "versionEndExcluding": "6.6", "versionStartIncluding": "6.5.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "5BEAFABA-7E5B-445F-93D8-C490B82429EC", "versionEndExcluding": "6.6.140", "versionStartIncluding": "6.6.3", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "269B1B34-9934-4742-8224-E11B647B979B", "versionEndExcluding": "6.12.88", "versionStartIncluding": "6.7.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BF39AE08-AE6D-4410-8FBE-76F6BF5BF55B", "versionEndExcluding": "6.18.30", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D0893CA7-9AE6-4DFE-AC75-48967D73AD8E", "versionEndExcluding": "7.0.7", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:-:*:*:*:*:*:*", "matchCriteriaId": "62B55B1B-7D3E-499B-9C42-E9F1EF05A54A", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc2:*:*:*:*:*:*", "matchCriteriaId": "E31AD4FC-436C-44AB-BCAB-3A0B37F69EE0", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc3:*:*:*:*:*:*", "matchCriteriaId": "C56C6E04-4F04-44A3-8DB8-93899903CFCF", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc4:*:*:*:*:*:*", "matchCriteriaId": "5C78EDA4-8BE6-42FC-9512-49032D525A55", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc5:*:*:*:*:*:*", "matchCriteriaId": "32F2E5CA-13C6-4601-B530-D465CBF73D1C", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc6:*:*:*:*:*:*", "matchCriteriaId": "5ED5AF93-F831-48BC-9545-CCB344E814FC", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc7:*:*:*:*:*:*", "matchCriteriaId": "81A7ABCB-0807-4AA2-8F4E-75E38D2E3FD4", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.7:rc8:*:*:*:*:*:*", "matchCriteriaId": "B01471D6-2DB4-4AF2-8BE0-B5082B4B9253", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: stmmac: Prevent NULL deref when RX memory exhausted\n\nThe CPU receives frames from the MAC through conventional DMA: the CPU\nallocates buffers for the MAC, then the MAC fills them and returns\nownership to the CPU. For each hardware RX queue, the CPU and MAC\ncoordinate through a shared ring array of DMA descriptors: one\ndescriptor per DMA buffer. Each descriptor includes the buffer's\nphysical address and a status flag (\"OWN\") indicating which side owns\nthe buffer: OWN=0 for CPU, OWN=1 for MAC. The CPU is only allowed to set\nthe flag and the MAC is only allowed to clear it, and both must move\nthrough the ring in sequence: thus the ring is used for both\n\"submissions\" and \"completions.\"\n\nIn the stmmac driver, stmmac_rx() bookmarks its position in the ring\nwith the `cur_rx` index. The main receive loop in that function checks\nfor rx_descs[cur_rx].own=0, gives the corresponding buffer to the\nnetwork stack (NULLing the pointer), and increments `cur_rx` modulo the\nring size. After the loop exits, stmmac_rx_refill(), which bookmarks its\nposition with `dirty_rx`, allocates fresh buffers and rearms the\ndescriptors (setting OWN=1). If it fails any allocation, it simply stops\nearly (leaving OWN=0) and will retry where it left off when next called.\n\nThis means descriptors have a three-stage lifecycle (terms my own):\n- `empty` (OWN=1, buffer valid)\n- `full` (OWN=0, buffer valid and populated)\n- `dirty` (OWN=0, buffer NULL)\n\nBut because stmmac_rx() only checks OWN, it confuses `full`/`dirty`. In\nthe past (see 'Fixes:'), there was a bug where the loop could cycle\n`cur_rx` all the way back to the first descriptor it dirtied, resulting\nin a NULL dereference when mistaken for `full`. The aforementioned\ncommit resolved that *specific* failure by capping the loop's iteration\nlimit at `dma_rx_size - 1`, but this is only a partial fix: if the\nprevious stmmac_rx_refill() didn't complete, then there are leftover\n`dirty` descriptors that the loop might encounter without needing to\ncycle fully around. The current code therefore panics (see 'Closes:')\nwhen stmmac_rx_refill() is memory-starved long enough for `cur_rx` to\ncatch up to `dirty_rx`.\n\nFix this by explicitly checking, before advancing `cur_rx`, if the next\nentry is dirty; exit the loop if so. This prevents processing of the\nfinal, used descriptor until stmmac_rx_refill() succeeds, but\nfully prevents the `cur_rx == dirty_rx` ambiguity as the previous bugfix\nintended: so remove the clamp as well. Since stmmac_rx_zc() is a\ncopy-paste-and-tweak of stmmac_rx() and the code structure is identical,\nany fix to stmmac_rx() will also need a corresponding fix for\nstmmac_rx_zc(). Therefore, apply the same check there.\n\nIn stmmac_rx() (not stmmac_rx_zc()), a related bug remains: after the\nMAC sets OWN=0 on the final descriptor, it will be unable to send any\nfurther DMA-complete IRQs until it's given more `empty` descriptors.\nCurrently, the driver simply *hopes* that the next stmmac_rx_refill()\nsucceeds, risking an indefinite stall of the receive process if not. But\nthis is not a regression, so it can be addressed in a future change."}], "id": "CVE-2026-46110", "lastModified": "2026-10-15T02:19:43.550", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-05-28T10:16:26.420", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0bb05e6adfa99a2ea1fee1125cc0953409f83ed8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4af2e62cbcda575a174acd230c3f3a208135e16d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5c910f7708e3c507b037ca91ca5b09f8cfe71e65"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/950cb436165aad0f8f2cd49da3cd07677465bcde"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e1c50b273298c7cd9b08b113e7a7598b531a02f5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/fdeb95b1fc7de25c9362990efb9996a8d761055c"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "nvd@nist.gov", "type": "Primary"}]}