CVE-2021-47118 (GCVE-0-2021-47118)

Vulnerability from cvelistv5 – Published: 2024-03-15 20:14 – Updated: 2025-05-04 07:04
VLAI?
Title
pid: take a reference when initializing `cad_pid`
Summary
In the Linux kernel, the following vulnerability has been resolved: pid: take a reference when initializing `cad_pid` During boot, kernel_init_freeable() initializes `cad_pid` to the init task's struct pid. Later on, we may change `cad_pid` via a sysctl, and when this happens proc_do_cad_pid() will increment the refcount on the new pid via get_pid(), and will decrement the refcount on the old pid via put_pid(). As we never called get_pid() when we initialized `cad_pid`, we decrement a reference we never incremented, can therefore free the init task's struct pid early. As there can be dangling references to the struct pid, we can later encounter a use-after-free (e.g. when delivering signals). This was spotted when fuzzing v5.13-rc3 with Syzkaller, but seems to have been around since the conversion of `cad_pid` to struct pid in commit 9ec52099e4b8 ("[PATCH] replace cad_pid by a struct pid") from the pre-KASAN stone age of v2.6.19. Fix this by getting a reference to the init task's struct pid when we assign it to `cad_pid`. Full KASAN splat below. ================================================================== BUG: KASAN: use-after-free in ns_of_pid include/linux/pid.h:153 [inline] BUG: KASAN: use-after-free in task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509 Read of size 4 at addr ffff23794dda0004 by task syz-executor.0/273 CPU: 1 PID: 273 Comm: syz-executor.0 Not tainted 5.12.0-00001-g9aef892b2d15 #1 Hardware name: linux,dummy-virt (DT) Call trace: ns_of_pid include/linux/pid.h:153 [inline] task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509 do_notify_parent+0x308/0xe60 kernel/signal.c:1950 exit_notify kernel/exit.c:682 [inline] do_exit+0x2334/0x2bd0 kernel/exit.c:845 do_group_exit+0x108/0x2c8 kernel/exit.c:922 get_signal+0x4e4/0x2a88 kernel/signal.c:2781 do_signal arch/arm64/kernel/signal.c:882 [inline] do_notify_resume+0x300/0x970 arch/arm64/kernel/signal.c:936 work_pending+0xc/0x2dc Allocated by task 0: slab_post_alloc_hook+0x50/0x5c0 mm/slab.h:516 slab_alloc_node mm/slub.c:2907 [inline] slab_alloc mm/slub.c:2915 [inline] kmem_cache_alloc+0x1f4/0x4c0 mm/slub.c:2920 alloc_pid+0xdc/0xc00 kernel/pid.c:180 copy_process+0x2794/0x5e18 kernel/fork.c:2129 kernel_clone+0x194/0x13c8 kernel/fork.c:2500 kernel_thread+0xd4/0x110 kernel/fork.c:2552 rest_init+0x44/0x4a0 init/main.c:687 arch_call_rest_init+0x1c/0x28 start_kernel+0x520/0x554 init/main.c:1064 0x0 Freed by task 270: slab_free_hook mm/slub.c:1562 [inline] slab_free_freelist_hook+0x98/0x260 mm/slub.c:1600 slab_free mm/slub.c:3161 [inline] kmem_cache_free+0x224/0x8e0 mm/slub.c:3177 put_pid.part.4+0xe0/0x1a8 kernel/pid.c:114 put_pid+0x30/0x48 kernel/pid.c:109 proc_do_cad_pid+0x190/0x1b0 kernel/sysctl.c:1401 proc_sys_call_handler+0x338/0x4b0 fs/proc/proc_sysctl.c:591 proc_sys_write+0x34/0x48 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1977 [inline] new_sync_write+0x3ac/0x510 fs/read_write.c:518 vfs_write fs/read_write.c:605 [inline] vfs_write+0x9c4/0x1018 fs/read_write.c:585 ksys_write+0x124/0x240 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __arm64_sys_write+0x78/0xb0 fs/read_write.c:667 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall arch/arm64/kernel/syscall.c:49 [inline] el0_svc_common.constprop.1+0x16c/0x388 arch/arm64/kernel/syscall.c:129 do_el0_svc+0xf8/0x150 arch/arm64/kernel/syscall.c:168 el0_svc+0x28/0x38 arch/arm64/kernel/entry-common.c:416 el0_sync_handler+0x134/0x180 arch/arm64/kernel/entry-common.c:432 el0_sync+0x154/0x180 arch/arm64/kernel/entry.S:701 The buggy address belongs to the object at ffff23794dda0000 which belongs to the cache pid of size 224 The buggy address is located 4 bytes inside of 224-byte region [ff ---truncated---
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < 764c2e892d1fe895392aff62fb353fdce43bb529 (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < f86c80515a8a3703e0ca2e56deb50fc2879c5ea4 (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < 4dbd8808a591b49b717862e6e0081bcf14a87788 (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < d106f05432e60f9f62d456ef017687f5c73cb414 (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < 2cd6eedfa6344f5ef5c3dac3aee57a39b5b46dff (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < 7178be006d495ffb741c329012da289b62dddfe6 (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < b8ff869f20152fbe66b6c2e2715d26a2f9897cca (git)
Affected: 9ec52099e4b8678a60e9f93e41ad87885d64f3e6 , < 0711f0d7050b9e07c44bc159bbc64ac0a1022c7f (git)
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    Linux Linux Affected: 2.6.19
Unaffected: 0 , < 2.6.19 (semver)
Unaffected: 4.4.272 , ≤ 4.4.* (semver)
Unaffected: 4.9.272 , ≤ 4.9.* (semver)
Unaffected: 4.14.236 , ≤ 4.14.* (semver)
Unaffected: 4.19.194 , ≤ 4.19.* (semver)
Unaffected: 5.4.125 , ≤ 5.4.* (semver)
Unaffected: 5.10.43 , ≤ 5.10.* (semver)
Unaffected: 5.12.10 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npid: take a reference when initializing `cad_pid`\n\nDuring boot, kernel_init_freeable() initializes `cad_pid` to the init\ntask\u0027s struct pid.  Later on, we may change `cad_pid` via a sysctl, and\nwhen this happens proc_do_cad_pid() will increment the refcount on the\nnew pid via get_pid(), and will decrement the refcount on the old pid\nvia put_pid().  As we never called get_pid() when we initialized\n`cad_pid`, we decrement a reference we never incremented, can therefore\nfree the init task\u0027s struct pid early.  As there can be dangling\nreferences to the struct pid, we can later encounter a use-after-free\n(e.g.  when delivering signals).\n\nThis was spotted when fuzzing v5.13-rc3 with Syzkaller, but seems to\nhave been around since the conversion of `cad_pid` to struct pid in\ncommit 9ec52099e4b8 (\"[PATCH] replace cad_pid by a struct pid\") from the\npre-KASAN stone age of v2.6.19.\n\nFix this by getting a reference to the init task\u0027s struct pid when we\nassign it to `cad_pid`.\n\nFull KASAN splat below.\n\n   ==================================================================\n   BUG: KASAN: use-after-free in ns_of_pid include/linux/pid.h:153 [inline]\n   BUG: KASAN: use-after-free in task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509\n   Read of size 4 at addr ffff23794dda0004 by task syz-executor.0/273\n\n   CPU: 1 PID: 273 Comm: syz-executor.0 Not tainted 5.12.0-00001-g9aef892b2d15 #1\n   Hardware name: linux,dummy-virt (DT)\n   Call trace:\n    ns_of_pid include/linux/pid.h:153 [inline]\n    task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509\n    do_notify_parent+0x308/0xe60 kernel/signal.c:1950\n    exit_notify kernel/exit.c:682 [inline]\n    do_exit+0x2334/0x2bd0 kernel/exit.c:845\n    do_group_exit+0x108/0x2c8 kernel/exit.c:922\n    get_signal+0x4e4/0x2a88 kernel/signal.c:2781\n    do_signal arch/arm64/kernel/signal.c:882 [inline]\n    do_notify_resume+0x300/0x970 arch/arm64/kernel/signal.c:936\n    work_pending+0xc/0x2dc\n\n   Allocated by task 0:\n    slab_post_alloc_hook+0x50/0x5c0 mm/slab.h:516\n    slab_alloc_node mm/slub.c:2907 [inline]\n    slab_alloc mm/slub.c:2915 [inline]\n    kmem_cache_alloc+0x1f4/0x4c0 mm/slub.c:2920\n    alloc_pid+0xdc/0xc00 kernel/pid.c:180\n    copy_process+0x2794/0x5e18 kernel/fork.c:2129\n    kernel_clone+0x194/0x13c8 kernel/fork.c:2500\n    kernel_thread+0xd4/0x110 kernel/fork.c:2552\n    rest_init+0x44/0x4a0 init/main.c:687\n    arch_call_rest_init+0x1c/0x28\n    start_kernel+0x520/0x554 init/main.c:1064\n    0x0\n\n   Freed by task 270:\n    slab_free_hook mm/slub.c:1562 [inline]\n    slab_free_freelist_hook+0x98/0x260 mm/slub.c:1600\n    slab_free mm/slub.c:3161 [inline]\n    kmem_cache_free+0x224/0x8e0 mm/slub.c:3177\n    put_pid.part.4+0xe0/0x1a8 kernel/pid.c:114\n    put_pid+0x30/0x48 kernel/pid.c:109\n    proc_do_cad_pid+0x190/0x1b0 kernel/sysctl.c:1401\n    proc_sys_call_handler+0x338/0x4b0 fs/proc/proc_sysctl.c:591\n    proc_sys_write+0x34/0x48 fs/proc/proc_sysctl.c:617\n    call_write_iter include/linux/fs.h:1977 [inline]\n    new_sync_write+0x3ac/0x510 fs/read_write.c:518\n    vfs_write fs/read_write.c:605 [inline]\n    vfs_write+0x9c4/0x1018 fs/read_write.c:585\n    ksys_write+0x124/0x240 fs/read_write.c:658\n    __do_sys_write fs/read_write.c:670 [inline]\n    __se_sys_write fs/read_write.c:667 [inline]\n    __arm64_sys_write+0x78/0xb0 fs/read_write.c:667\n    __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]\n    invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]\n    el0_svc_common.constprop.1+0x16c/0x388 arch/arm64/kernel/syscall.c:129\n    do_el0_svc+0xf8/0x150 arch/arm64/kernel/syscall.c:168\n    el0_svc+0x28/0x38 arch/arm64/kernel/entry-common.c:416\n    el0_sync_handler+0x134/0x180 arch/arm64/kernel/entry-common.c:432\n    el0_sync+0x154/0x180 arch/arm64/kernel/entry.S:701\n\n   The buggy address belongs to the object at ffff23794dda0000\n    which belongs to the cache pid of size 224\n   The buggy address is located 4 bytes inside of\n    224-byte region [ff\n---truncated---"
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      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://git.kernel.org/stable/c/764c2e892d1fe895392aff62fb353fdce43bb529\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/f86c80515a8a3703e0ca2e56deb50fc2879c5ea4\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/4dbd8808a591b49b717862e6e0081bcf14a87788\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/d106f05432e60f9f62d456ef017687f5c73cb414\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/2cd6eedfa6344f5ef5c3dac3aee57a39b5b46dff\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/7178be006d495ffb741c329012da289b62dddfe6\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/b8ff869f20152fbe66b6c2e2715d26a2f9897cca\", \"tags\": [\"x_transferred\"]}, {\"url\": \"https://git.kernel.org/stable/c/0711f0d7050b9e07c44bc159bbc64ac0a1022c7f\", \"tags\": [\"x_transferred\"]}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2024-08-04T05:24:39.826Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2021-47118\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2024-09-10T15:55:32.497500Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2024-09-11T12:42:16.627Z\"}}], \"cna\": {\"title\": \"pid: take a reference when initializing `cad_pid`\", \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"764c2e892d1fe895392aff62fb353fdce43bb529\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"f86c80515a8a3703e0ca2e56deb50fc2879c5ea4\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"4dbd8808a591b49b717862e6e0081bcf14a87788\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"d106f05432e60f9f62d456ef017687f5c73cb414\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"2cd6eedfa6344f5ef5c3dac3aee57a39b5b46dff\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"7178be006d495ffb741c329012da289b62dddfe6\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"b8ff869f20152fbe66b6c2e2715d26a2f9897cca\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9ec52099e4b8678a60e9f93e41ad87885d64f3e6\", \"lessThan\": \"0711f0d7050b9e07c44bc159bbc64ac0a1022c7f\", \"versionType\": \"git\"}], \"programFiles\": [\"init/main.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"2.6.19\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"2.6.19\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"4.4.272\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.4.*\"}, {\"status\": \"unaffected\", \"version\": \"4.9.272\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.9.*\"}, {\"status\": \"unaffected\", \"version\": \"4.14.236\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.14.*\"}, {\"status\": \"unaffected\", \"version\": \"4.19.194\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"4.19.*\"}, {\"status\": \"unaffected\", \"version\": \"5.4.125\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.4.*\"}, {\"status\": \"unaffected\", \"version\": \"5.10.43\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.12.10\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.12.*\"}, {\"status\": \"unaffected\", \"version\": \"5.13\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"init/main.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/764c2e892d1fe895392aff62fb353fdce43bb529\"}, {\"url\": \"https://git.kernel.org/stable/c/f86c80515a8a3703e0ca2e56deb50fc2879c5ea4\"}, {\"url\": \"https://git.kernel.org/stable/c/4dbd8808a591b49b717862e6e0081bcf14a87788\"}, {\"url\": \"https://git.kernel.org/stable/c/d106f05432e60f9f62d456ef017687f5c73cb414\"}, {\"url\": \"https://git.kernel.org/stable/c/2cd6eedfa6344f5ef5c3dac3aee57a39b5b46dff\"}, {\"url\": \"https://git.kernel.org/stable/c/7178be006d495ffb741c329012da289b62dddfe6\"}, {\"url\": \"https://git.kernel.org/stable/c/b8ff869f20152fbe66b6c2e2715d26a2f9897cca\"}, {\"url\": \"https://git.kernel.org/stable/c/0711f0d7050b9e07c44bc159bbc64ac0a1022c7f\"}], \"x_generator\": {\"engine\": \"bippy-5f407fcff5a0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\npid: take a reference when initializing `cad_pid`\\n\\nDuring boot, kernel_init_freeable() initializes `cad_pid` to the init\\ntask\u0027s struct pid.  Later on, we may change `cad_pid` via a sysctl, and\\nwhen this happens proc_do_cad_pid() will increment the refcount on the\\nnew pid via get_pid(), and will decrement the refcount on the old pid\\nvia put_pid().  As we never called get_pid() when we initialized\\n`cad_pid`, we decrement a reference we never incremented, can therefore\\nfree the init task\u0027s struct pid early.  As there can be dangling\\nreferences to the struct pid, we can later encounter a use-after-free\\n(e.g.  when delivering signals).\\n\\nThis was spotted when fuzzing v5.13-rc3 with Syzkaller, but seems to\\nhave been around since the conversion of `cad_pid` to struct pid in\\ncommit 9ec52099e4b8 (\\\"[PATCH] replace cad_pid by a struct pid\\\") from the\\npre-KASAN stone age of v2.6.19.\\n\\nFix this by getting a reference to the init task\u0027s struct pid when we\\nassign it to `cad_pid`.\\n\\nFull KASAN splat below.\\n\\n   ==================================================================\\n   BUG: KASAN: use-after-free in ns_of_pid include/linux/pid.h:153 [inline]\\n   BUG: KASAN: use-after-free in task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509\\n   Read of size 4 at addr ffff23794dda0004 by task syz-executor.0/273\\n\\n   CPU: 1 PID: 273 Comm: syz-executor.0 Not tainted 5.12.0-00001-g9aef892b2d15 #1\\n   Hardware name: linux,dummy-virt (DT)\\n   Call trace:\\n    ns_of_pid include/linux/pid.h:153 [inline]\\n    task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509\\n    do_notify_parent+0x308/0xe60 kernel/signal.c:1950\\n    exit_notify kernel/exit.c:682 [inline]\\n    do_exit+0x2334/0x2bd0 kernel/exit.c:845\\n    do_group_exit+0x108/0x2c8 kernel/exit.c:922\\n    get_signal+0x4e4/0x2a88 kernel/signal.c:2781\\n    do_signal arch/arm64/kernel/signal.c:882 [inline]\\n    do_notify_resume+0x300/0x970 arch/arm64/kernel/signal.c:936\\n    work_pending+0xc/0x2dc\\n\\n   Allocated by task 0:\\n    slab_post_alloc_hook+0x50/0x5c0 mm/slab.h:516\\n    slab_alloc_node mm/slub.c:2907 [inline]\\n    slab_alloc mm/slub.c:2915 [inline]\\n    kmem_cache_alloc+0x1f4/0x4c0 mm/slub.c:2920\\n    alloc_pid+0xdc/0xc00 kernel/pid.c:180\\n    copy_process+0x2794/0x5e18 kernel/fork.c:2129\\n    kernel_clone+0x194/0x13c8 kernel/fork.c:2500\\n    kernel_thread+0xd4/0x110 kernel/fork.c:2552\\n    rest_init+0x44/0x4a0 init/main.c:687\\n    arch_call_rest_init+0x1c/0x28\\n    start_kernel+0x520/0x554 init/main.c:1064\\n    0x0\\n\\n   Freed by task 270:\\n    slab_free_hook mm/slub.c:1562 [inline]\\n    slab_free_freelist_hook+0x98/0x260 mm/slub.c:1600\\n    slab_free mm/slub.c:3161 [inline]\\n    kmem_cache_free+0x224/0x8e0 mm/slub.c:3177\\n    put_pid.part.4+0xe0/0x1a8 kernel/pid.c:114\\n    put_pid+0x30/0x48 kernel/pid.c:109\\n    proc_do_cad_pid+0x190/0x1b0 kernel/sysctl.c:1401\\n    proc_sys_call_handler+0x338/0x4b0 fs/proc/proc_sysctl.c:591\\n    proc_sys_write+0x34/0x48 fs/proc/proc_sysctl.c:617\\n    call_write_iter include/linux/fs.h:1977 [inline]\\n    new_sync_write+0x3ac/0x510 fs/read_write.c:518\\n    vfs_write fs/read_write.c:605 [inline]\\n    vfs_write+0x9c4/0x1018 fs/read_write.c:585\\n    ksys_write+0x124/0x240 fs/read_write.c:658\\n    __do_sys_write fs/read_write.c:670 [inline]\\n    __se_sys_write fs/read_write.c:667 [inline]\\n    __arm64_sys_write+0x78/0xb0 fs/read_write.c:667\\n    __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]\\n    invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]\\n    el0_svc_common.constprop.1+0x16c/0x388 arch/arm64/kernel/syscall.c:129\\n    do_el0_svc+0xf8/0x150 arch/arm64/kernel/syscall.c:168\\n    el0_svc+0x28/0x38 arch/arm64/kernel/entry-common.c:416\\n    el0_sync_handler+0x134/0x180 arch/arm64/kernel/entry-common.c:432\\n    el0_sync+0x154/0x180 arch/arm64/kernel/entry.S:701\\n\\n   The buggy address belongs to the object at ffff23794dda0000\\n    which belongs to the cache pid of size 224\\n   The buggy address is located 4 bytes inside of\\n    224-byte region [ff\\n---truncated---\"}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2024-12-19T07:35:33.871Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2021-47118\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2024-12-19T07:35:33.871Z\", \"dateReserved\": \"2024-03-04T18:12:48.838Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-03-15T20:14:25.116Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.