{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2022-49393", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-02-26T02:08:31.562Z", "datePublished": "2025-02-26T02:11:24.730Z", "dateUpdated": "2026-08-05T08:55:00.985Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:55:00.985Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmisc: fastrpc: fix list iterator in fastrpc_req_mem_unmap_impl\n\nThis is another instance of incorrect use of list iterator and\nchecking it for NULL.\n\nThe list iterator value 'map' will *always* be set and non-NULL\nby list_for_each_entry(), so it is incorrect to assume that the\niterator value will be NULL if the list is empty (in this case, the\ncheck 'if (!map) {' will always be false and never exit as expected).\n\nTo fix the bug, use a new variable 'iter' as the list iterator,\nwhile use the original variable 'map' as a dedicated pointer to\npoint to the found element.\n\nWithout this patch, Kernel crashes with below trace:\n\nUnable to handle kernel access to user memory outside uaccess routines\n at virtual address 0000ffff7fb03750\n...\nCall trace:\n fastrpc_map_create+0x70/0x290 [fastrpc]\n fastrpc_req_mem_map+0xf0/0x2dc [fastrpc]\n fastrpc_device_ioctl+0x138/0xc60 [fastrpc]\n __arm64_sys_ioctl+0xa8/0xec\n invoke_syscall+0x48/0x114\n el0_svc_common.constprop.0+0xd4/0xfc\n do_el0_svc+0x28/0x90\n el0_svc+0x3c/0x130\n el0t_64_sync_handler+0xa4/0x130\n el0t_64_sync+0x18c/0x190\nCode: 14000016 f94000a5 eb05029f 54000260 (b94018a6)\n---[ end trace 0000000000000000 ]---" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached via FASTRPC_IOCTL_MEM_UNMAP (and the MEM_MAP copy_to_user failure cleanup) on the local /dev/fastrpc-* misc device ioctl path, not via network or adjacent protocols.\nAC:L - An attacker who can open the device can populate fl->maps and then issue MEM_UNMAP with a non-matching fd/vaddr (or force the MEM_MAP cleanup path), reliably taking the bad iterator path with no race or victim-controlled timing.\nPR:L - fastrpc_device_open and the MEM_MAP/MEM_UNMAP ioctls have no capability checks; on Qualcomm/Android deployments unprivileged apps can obtain FastRPC device access (directly or via DSP HAL FD passing), so only low local privileges are required.\nUI:N - Exploitation requires no victim action; the attacker triggers the vulnerable ioctl sequence themselves once they have the device file descriptor.\nS:U - Impact is kernel memory corruption / privilege escalation within the host Linux kernel authority; it does not by itself cross a VM, IOMMU, or other separate security boundary.\nC:H - The failed lookup leaves map as a type-confused pointer into fastrpc_user, then reads forged map fields and can drive fastrpc_free_map/kfree on that object, yielding heap corruption that can be leveraged for arbitrary kernel read under the required uncertainty rule.\nI:H - Calling fastrpc_map_put on the bogus map can invoke fastrpc_free_map and kfree an interior pointer into the fastrpc_user allocation, producing heap metadata corruption exploitable for arbitrary write / control-flow hijacking.\nA:H - The commit documents a kernel oops from corrupted pointer dereference (userspace address used as a kernel pointer), so availability impact is a full kernel crash." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/misc/fastrpc.c" ], "versions": [ { "version": "5c1b97c7d7b736e6439af4f43a65837bc72f56c1", "lessThan": "2d12905aad462383f4e7a5fdb024d2b7ae2d10cf", "status": "affected", "versionType": "git" }, { "version": "5c1b97c7d7b736e6439af4f43a65837bc72f56c1", "lessThan": "c5c07c5958cf0c9af6e76813e6de15d42ee49822", "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/misc/fastrpc.c" ], "versions": [ { "version": "5.18", "status": "affected" }, { "version": "0", "lessThan": "5.18", "status": "unaffected", "versionType": "semver" }, { "version": "5.18.3", "lessThanOrEqual": "5.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.19", "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": "5.18", "versionEndExcluding": "5.18.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "5.19" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/2d12905aad462383f4e7a5fdb024d2b7ae2d10cf" }, { "url": "https://git.kernel.org/stable/c/c5c07c5958cf0c9af6e76813e6de15d42ee49822" } ], "title": "misc: fastrpc: fix list iterator in fastrpc_req_mem_unmap_impl", "x_generator": { "engine": "bippy-1.2.0" } } } }