{"id":"CVE-2023-53578","title":"net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()\n\nSyzbot reported a bug as following:\n\n=====================================================\nBUG: KMSAN:…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 3814d211ff13ee35f2d9437439a6c7df58524137","Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < c6a796ee5a639ffb83c6e5469408cc2ec16cac6a","Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < bef57c227b52c2bde00fad33556175d36d12cfa0","Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 8c9ce34a6ff2c544f96ce0b088e8fd3c1b9698c4","Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 6417070918de3bcdbe0646e7256dae58fd8083ba","Linux 5.6"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:24:21.438547Z"},"published":"2025-10-04","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:31:15.588Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-53578","references":[{"url":"https://git.kernel.org/stable/c/3814d211ff13ee35f2d9437439a6c7df58524137"},{"url":"https://git.kernel.org/stable/c/c6a796ee5a639ffb83c6e5469408cc2ec16cac6a"},{"url":"https://git.kernel.org/stable/c/bef57c227b52c2bde00fad33556175d36d12cfa0"},{"url":"https://git.kernel.org/stable/c/8c9ce34a6ff2c544f96ce0b088e8fd3c1b9698c4"},{"url":"https://git.kernel.org/stable/c/6417070918de3bcdbe0646e7256dae58fd8083ba"}],"tags":["cve.org"],"epss":0.00156,"epssPercentile":0.04792,"ingestedAt":"2026-11-05T22:38:31.813Z","slug":"CVE-2023-53578","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()\n\nSyzbot reported a bug as following:\n\n=====================================================\nBUG: KMSAN: uninit-value in qrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230\n qrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230\n qrtr_endpoint_post+0xf85/0x11b0 net/qrtr/af_qrtr.c:519\n qrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108\n call_write_iter include/linux/fs.h:2189 [inline]\n aio_write+0x63a/0x950 fs/aio.c:1600\n io_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019\n __do_sys_io_submit fs/aio.c:2078 [inline]\n __se_sys_io_submit+0x293/0x770 fs/aio.c:2048\n __x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nUninit was created at:\n slab_post_alloc_hook mm/slab.h:766 [inline]\n slab_alloc_node mm/slub.c:3452 [inline]\n __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491\n __do_kmalloc_node mm/slab_common.c:967 [inline]\n __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988\n kmalloc_reserve net/core/skbuff.c:492 [inline]\n __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565\n __netdev_alloc_skb+0x120/0x7d0 net/core/skbuff.c:630\n qrtr_endpoint_post+0xbd/0x11b0 net/qrtr/af_qrtr.c:446\n qrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108\n call_write_iter include/linux/fs.h:2189 [inline]\n aio_write+0x63a/0x950 fs/aio.c:1600\n io_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019\n __do_sys_io_submit fs/aio.c:2078 [inline]\n __se_sys_io_submit+0x293/0x770 fs/aio.c:2048\n __x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nIt is because that skb->len requires at least sizeof(struct qrtr_ctrl_pkt)\nin qrtr_tx_resume(). And skb->len equals to size in qrtr_endpoint_post().\nBut size is less than sizeof(struct qrtr_ctrl_pkt) when qrtr_cb->type\nequals to QRTR_TYPE_RESUME_TX in qrtr_endpoint_post() under the syzbot\nscenario. This triggers the uninit variable access bug.\n\nAdd size check when qrtr_cb->type equals to QRTR_TYPE_RESUME_TX in\nqrtr_endpoint_post() to fix the bug.\n\n## Affected\n\n- `Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 3814d211ff13ee35f2d9437439a6c7df58524137`\n- `Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < c6a796ee5a639ffb83c6e5469408cc2ec16cac6a`\n- `Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < bef57c227b52c2bde00fad33556175d36d12cfa0`\n- `Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 8c9ce34a6ff2c544f96ce0b088e8fd3c1b9698c4`\n- `Linux >= 5fdeb0d372ab33b4175043a2a4a1730239a217f1 < 6417070918de3bcdbe0646e7256dae58fd8083ba`\n- `Linux 5.6`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}