{
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    "CVE_data_meta": {
        "ID": "CVE-2024-40910",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
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    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nax25: Fix refcount imbalance on inbound connections\n\nWhen releasing a socket in ax25_release(), we call netdev_put() to\ndecrease the refcount on the associated ax.25 device. However, the\nexecution path for accepting an incoming connection never calls\nnetdev_hold(). This imbalance leads to refcount errors, and ultimately\nto kernel crashes.\n\nA typical call trace for the above situation will start with one of the\nfollowing errors:\n\n    refcount_t: decrement hit 0; leaking memory.\n    refcount_t: underflow; use-after-free.\n\nAnd will then have a trace like:\n\n    Call Trace:\n    <TASK>\n    ? show_regs+0x64/0x70\n    ? __warn+0x83/0x120\n    ? refcount_warn_saturate+0xb2/0x100\n    ? report_bug+0x158/0x190\n    ? prb_read_valid+0x20/0x30\n    ? handle_bug+0x3e/0x70\n    ? exc_invalid_op+0x1c/0x70\n    ? asm_exc_invalid_op+0x1f/0x30\n    ? refcount_warn_saturate+0xb2/0x100\n    ? refcount_warn_saturate+0xb2/0x100\n    ax25_release+0x2ad/0x360\n    __sock_release+0x35/0xa0\n    sock_close+0x19/0x20\n    [...]\n\nOn reboot (or any attempt to remove the interface), the kernel gets\nstuck in an infinite loop:\n\n    unregister_netdevice: waiting for ax0 to become free. Usage count = 0\n\nThis patch corrects these issues by ensuring that we call netdev_hold()\nand ax25_dev_hold() for new connections in ax25_accept(). This makes the\nlogic leading to ax25_accept() match the logic for ax25_bind(): in both\ncases we increment the refcount, which is ultimately decremented in\nax25_release()."
            }
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                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
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                    "vendor_name": "Linux",
                    "product": {
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                                "product_name": "Linux",
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                                            "version_value": "f4df9d6c8d4e"
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                                                        "version": "5.18",
                                                        "status": "affected"
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                                                        "version": "0",
                                                        "lessThan": "5.18",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
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                                                        "version": "6.1.95",
                                                        "lessThanOrEqual": "6.1.*",
                                                        "status": "unaffected",
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                                                    {
                                                        "version": "6.6.35",
                                                        "lessThanOrEqual": "6.6.*",
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                                                        "version": "6.9.6",
                                                        "lessThanOrEqual": "6.9.*",
                                                        "status": "unaffected",
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                                                        "version": "6.10",
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