{"cve":"CVE-2024-26766","nvd":{"published":"2024-04-03T17:15:52.683","modified":"2026-08-04T11:17:02.050","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nIB/hfi1: Fix sdma.h tx->num_descs off-by-one error\n\nUnfortunately the commit `fd8958efe877` introduced another error\ncausing the `descs` array to overflow. This reults in further crashes\neasily reproducible by `sendmsg` system call.\n\n[ 1080.836473] general protection fault, probably for non-canonical address 0x400300015528b00a: 0000 [#1] PREEMPT SMP PTI\n[ 1080.869326] RIP: 0010:hfi1_ipoib_build_ib_tx_headers.constprop.0+0xe1/0x2b0 [hfi1]\n--\n[ 1080.974535] Call Trace:\n[ 1080.976990]  <TASK>\n[ 1081.021929]  hfi1_ipoib_send_dma_common+0x7a/0x2e0 [hfi1]\n[ 1081.027364]  hfi1_ipoib_send_dma_list+0x62/0x270 [hfi1]\n[ 1081.032633]  hfi1_ipoib_send+0x112/0x300 [hfi1]\n[ 1081.042001]  ipoib_start_xmit+0x2a9/0x2d0 [ib_ipoib]\n[ 1081.046978]  dev_hard_start_xmit+0xc4/0x210\n--\n[ 1081.148347]  __sys_sendmsg+0x59/0xa0\n\ncrash> ipoib_txreq 0xffff9cfeba229f00\nstruct ipoib_txreq {\n  txreq = {\n    list = {\n      next = 0xffff9cfeba229f00,\n      prev = 0xffff9cfeba229f00\n    },\n    descp = 0xffff9cfeba229f40,\n    coalesce_buf = 0x0,\n    wait = 0xffff9cfea4e69a48,\n    complete = 0xffffffffc0fe0760 <hfi1_ipoib_sdma_complete>,\n    packet_len = 0x46d,\n    tlen = 0x0,\n    num_desc = 0x0,\n    desc_limit = 0x6,\n    next_descq_idx = 0x45c,\n    coalesce_idx = 0x0,\n    flags = 0x0,\n    descs = {{\n        qw = {0x8024000120dffb00, 0x4}  # SDMA_DESC0_FIRST_DESC_FLAG (bit 63)\n      }, {\n        qw = {  0x3800014231b108, 0x4}\n      }, {\n        qw = { 0x310000e4ee0fcf0, 0x8}\n      }, {\n        qw = {  0x3000012e9f8000, 0x8}\n      }, {\n        qw = {  0x59000dfb9d0000, 0x8}\n      }, {\n        qw = {  0x78000e02e40000, 0x8}\n      }}\n  },\n  sdma_hdr =  0x400300015528b000,  <<< invalid pointer in the tx request structure\n  sdma_status = 0x0,                   SDMA_DESC0_LAST_DESC_FLAG (bit 62)\n  complete = 0x0,\n  priv = 0x0,\n  txq = 0xffff9cfea4e69880,\n  skb = 0xffff9d099809f400\n}\n\nIf an SDMA send consists of exactly 6 descriptors and requires dword\npadding (in the 7th descriptor), the sdma_txreq descriptor array is not\nproperly expanded and the packet will overflow into the container\nstructure. This results in a panic when the send completion runs. The\nexact panic varies depending on what elements of the container structure\nget corrupted. The fix is to use the correct expression in\n_pad_sdma_tx_descs() to test the need to expand the descriptor array.\n\nWith this patch the crashes are no longer reproducible and the machine is\nstable.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-193"],"references":["https://git.kernel.org/stable/c/115b7f3bc1dce590a6851a2dcf23dc1100c49790","https://git.kernel.org/stable/c/3f38d22e645e2e994979426ea5a35186102ff3c2","https://git.kernel.org/stable/c/47ae64df23ed1318e27bd9844e135a5e1c0e6e39","https://git.kernel.org/stable/c/52dc9a7a573dbf778625a0efca0fca55489f084b","https://git.kernel.org/stable/c/5833024a9856f454a964a198c63a57e59e07baf5"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:47:51.568503435+00:00"},"epss":{"cve":"CVE-2024-26766","score":0.00268,"percentile":0.19008,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}