{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2022-50062", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-06-18T10:57:27.404Z", "datePublished": "2025-06-18T11:02:09.871Z", "dateUpdated": "2026-08-05T08:57:16.315Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:57:16.315Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bgmac: Fix a BUG triggered by wrong bytes_compl\n\nOn one of our machines we got:\n\nkernel BUG at lib/dynamic_queue_limits.c:27!\nInternal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM\nCPU: 0 PID: 1166 Comm: irq/41-bgmac Tainted: G W O 4.14.275-rt132 #1\nHardware name: BRCM XGS iProc\ntask: ee3415c0 task.stack: ee32a000\nPC is at dql_completed+0x168/0x178\nLR is at bgmac_poll+0x18c/0x6d8\npc : [] lr : [] psr: 800a0313\nsp : ee32be14 ip : 000005ea fp : 00000bd4\nr10: ee558500 r9 : c0116298 r8 : 00000002\nr7 : 00000000 r6 : ef128810 r5 : 01993267 r4 : 01993851\nr3 : ee558000 r2 : 000070e1 r1 : 00000bd4 r0 : ee52c180\nFlags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none\nControl: 12c5387d Table: 8e88c04a DAC: 00000051\nProcess irq/41-bgmac (pid: 1166, stack limit = 0xee32a210)\nStack: (0xee32be14 to 0xee32c000)\nbe00: ee558520 ee52c100 ef128810\nbe20: 00000000 00000002 c0116298 c04b5a18 00000000 c0a0c8c4 c0951780 00000040\nbe40: c0701780 ee558500 ee55d520 ef05b340 ef6f9780 ee558520 00000001 00000040\nbe60: ffffe000 c0a56878 ef6fa040 c0952040 0000012c c0528744 ef6f97b0 fffcfb6a\nbe80: c0a04104 2eda8000 c0a0c4ec c0a0d368 ee32bf44 c0153534 ee32be98 ee32be98\nbea0: ee32bea0 ee32bea0 ee32bea8 ee32bea8 00000000 c01462e4 ffffe000 ef6f22a8\nbec0: ffffe000 00000008 ee32bee4 c0147430 ffffe000 c094a2a8 00000003 ffffe000\nbee0: c0a54528 00208040 0000000c c0a0c8c4 c0a65980 c0124d3c 00000008 ee558520\nbf00: c094a23c c0a02080 00000000 c07a9910 ef136970 ef136970 ee30a440 ef136900\nbf20: ee30a440 00000001 ef136900 ee30a440 c016d990 00000000 c0108db0 c012500c\nbf40: ef136900 c016da14 ee30a464 ffffe000 00000001 c016dd14 00000000 c016db28\nbf60: ffffe000 ee21a080 ee30a400 00000000 ee32a000 ee30a440 c016dbfc ee25fd70\nbf80: ee21a09c c013edcc ee32a000 ee30a400 c013ec7c 00000000 00000000 00000000\nbfa0: 00000000 00000000 00000000 c0108470 00000000 00000000 00000000 00000000\nbfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000\nbfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000\n[] (dql_completed) from [] (bgmac_poll+0x18c/0x6d8)\n[] (bgmac_poll) from [] (net_rx_action+0x1c4/0x494)\n[] (net_rx_action) from [] (do_current_softirqs+0x1ec/0x43c)\n[] (do_current_softirqs) from [] (__local_bh_enable+0x80/0x98)\n[] (__local_bh_enable) from [] (irq_forced_thread_fn+0x84/0x98)\n[] (irq_forced_thread_fn) from [] (irq_thread+0x118/0x1c0)\n[] (irq_thread) from [] (kthread+0x150/0x158)\n[] (kthread) from [] (ret_from_fork+0x14/0x24)\nCode: a83f15e0 0200001a 0630a0e1 c3ffffea (f201f0e7)\n\nThe issue seems similar to commit 90b3b339364c (\"net: hisilicon: Fix a BUG\ntrigered by wrong bytes_compl\") and potentially introduced by commit\nb38c83dd0866 (\"bgmac: simplify tx ring index handling\").\n\nIf there is an RX interrupt between setting ring->end\nand netdev_sent_queue() we can hit the BUG_ON as bgmac_dma_tx_free()\ncan miscalculate the queue size while called from bgmac_poll().\n\nThe machine which triggered the BUG runs a v4.14 RT kernel - but the issue\nseems present in mainline too." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - bgmac is the Gigabit MAC on Broadcom iProc/XGS and BCM47xx platforms commonly used as routers and switches; an unauthenticated remote peer can drive concurrent TX (forwarded or reply traffic through bgmac_start_xmit) and RX interrupts that schedule bgmac_poll.\nAC:L - The race is between updating ring->end and netdev_sent_queue in bgmac_dma_tx_add versus bgmac_dma_tx_free from NAPI; the attacker can generate both TX and RX load to create that concurrency, so success does not depend on conditions outside attacker influence.\nPR:N - In the network-triggered forwarding/reply scenario, no local account or capability is required—only the ability to send packets that the device transmits and receives on the affected interface.\nUI:N - Exploitation needs no victim action beyond the interface already being up and carrying traffic.\nS:U - Impact is confined to the same host kernel availability domain; there is no VM escape, IOMMU bypass, or other cross-authority boundary crossing.\nC:N - The bug is a Byte Queue Limits accounting mismatch that trips BUG_ON in dql_completed; it does not disclose memory contents or create a read primitive.\nI:N - There is no memory corruption, attacker-controlled write, or control-flow hijack—only incorrect completed-byte accounting versus num_queued.\nA:H - Hitting BUG_ON(count > num_queued - dql->num_completed) in dql_completed causes a kernel BUG/oops (observed panic on BRCM XGS iProc), which is a full availability loss." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/broadcom/bgmac.c" ], "versions": [ { "version": "b38c83dd08665a93e439c4ffd9eef31bc098a6ea", "lessThan": "ac6d4482f29ab992b605c1b4bd1347f1f679f4e4", "status": "affected", "versionType": "git" }, { "version": "b38c83dd08665a93e439c4ffd9eef31bc098a6ea", "lessThan": "ab2b55bb25db289ba0b68e3d58494476bdb1041d", "status": "affected", "versionType": "git" }, { "version": "b38c83dd08665a93e439c4ffd9eef31bc098a6ea", "lessThan": "c506c9a97120f43257e9b3ce7b1f9a24eafc3787", "status": "affected", "versionType": "git" }, { "version": "b38c83dd08665a93e439c4ffd9eef31bc098a6ea", "lessThan": "da1421a29d3b8681ba6a7f686bd0b40dda5acaf3", "status": "affected", "versionType": "git" }, { "version": "b38c83dd08665a93e439c4ffd9eef31bc098a6ea", "lessThan": "1b7680c6c1f6de9904f1d9b05c952f0c64a03350", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/broadcom/bgmac.c" ], "versions": [ { "version": "4.1", "status": "affected" }, { "version": "0", "lessThan": "4.1", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.211", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.138", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.63", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.19.4", "lessThanOrEqual": "5.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.4.211" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.10.138" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.15.63" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.19.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ac6d4482f29ab992b605c1b4bd1347f1f679f4e4" }, { "url": "https://git.kernel.org/stable/c/ab2b55bb25db289ba0b68e3d58494476bdb1041d" }, { "url": "https://git.kernel.org/stable/c/c506c9a97120f43257e9b3ce7b1f9a24eafc3787" }, { "url": "https://git.kernel.org/stable/c/da1421a29d3b8681ba6a7f686bd0b40dda5acaf3" }, { "url": "https://git.kernel.org/stable/c/1b7680c6c1f6de9904f1d9b05c952f0c64a03350" } ], "title": "net: bgmac: Fix a BUG triggered by wrong bytes_compl", "x_generator": { "engine": "bippy-1.2.0" } } } }