In the Linux kernel, the following vulnerability has been resolved:
watch_queue: Actually free the watch
free_watch() does everything barring actually freeing the watch object. Fix this by adding the missing kfree.
kmemleak produces a report something like the following. Note that as an address can be seen in the first word, the watch would appear to have gone through call_rcu().
BUG: memory leak unreferenced object 0xffff88810ce4a200 (size 96): comm "syz-executor352", pid 3605, jiffies 4294947473 (age 13.720s) hex dump (first 32 bytes): e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H............. 80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8214e6cc>] kmalloc include/linux/slab.h:581 [inline] [<ffffffff8214e6cc>] kzalloc include/linux/slab.h:714 [inline] [<ffffffff8214e6cc>] keyctlwatchkey+0xec/0x2e0 security/keys/keyctl.c:1800 [<ffffffff8214ec84>] _dosyskeyctl+0x3c4/0x490 security/keys/keyctl.c:2016 [<ffffffff84493a25>] dosyscallx64 arch/x86/entry/common.c:50 [inline] [<ffffffff84493a25>] dosyscall64+0x35/0xb0 arch/x86/entry/common.c:80 [<ffffffff84600068>] entrySYSCALL64after_hwframe+0x44/0xae
{ "vanir_signatures": [ { "id": "CVE-2022-49256-14f31ba9", "signature_type": "Function", "target": { "file": "kernel/watch_queue.c", "function": "free_watch" }, "signature_version": "v1", "digest": { "length": 239.0, "function_hash": "313369638600437725296301508795684183997" }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b" }, { "id": "CVE-2022-49256-21ac7d2c", "signature_type": "Line", "target": { "file": "kernel/watch_queue.c" }, "signature_version": "v1", "digest": { "line_hashes": [ "157250318527350411482311974135296965183", "52223220505761765810701734288128941816", "285002072406242075875667332690023495805", "250904878208422252973913682585705122372" ], "threshold": 0.9 }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@7e8c9b0df07a77f0d072603b8ced2677e30e1893" }, { "id": "CVE-2022-49256-2e470408", "signature_type": "Line", "target": { "file": "kernel/watch_queue.c" }, "signature_version": "v1", "digest": { "line_hashes": [ "157250318527350411482311974135296965183", "52223220505761765810701734288128941816", "285002072406242075875667332690023495805", "250904878208422252973913682585705122372" ], "threshold": 0.9 }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@9d92be1a09fbb3dd65600dbfe7eedb40e7228e4b" }, { "id": "CVE-2022-49256-6161ec32", "signature_type": "Line", "target": { "file": "kernel/watch_queue.c" }, "signature_version": "v1", "digest": { "line_hashes": [ "157250318527350411482311974135296965183", "52223220505761765810701734288128941816", "285002072406242075875667332690023495805", "250904878208422252973913682585705122372" ], "threshold": 0.9 }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@f69aecb49968e14196366bbe896eab0a904229f5" }, { "id": "CVE-2022-49256-6291df7b", "signature_type": "Line", "target": { "file": "kernel/watch_queue.c" }, "signature_version": "v1", "digest": { "line_hashes": [ "157250318527350411482311974135296965183", "52223220505761765810701734288128941816", "285002072406242075875667332690023495805", "250904878208422252973913682585705122372" ], "threshold": 0.9 }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@3d8dcf278b1ee1eff1e90be848fa2237db4c07a7" }, { "id": "CVE-2022-49256-6fe4c569", "signature_type": "Function", "target": { "file": "kernel/watch_queue.c", "function": "free_watch" }, "signature_version": "v1", "digest": { "length": 239.0, "function_hash": "313369638600437725296301508795684183997" }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@f69aecb49968e14196366bbe896eab0a904229f5" }, { "id": "CVE-2022-49256-75170bf4", "signature_type": "Function", "target": { "file": "kernel/watch_queue.c", "function": "free_watch" }, "signature_version": "v1", "digest": { "length": 239.0, "function_hash": "313369638600437725296301508795684183997" }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@3d8dcf278b1ee1eff1e90be848fa2237db4c07a7" }, { "id": "CVE-2022-49256-c96e1d70", "signature_type": "Function", "target": { "file": "kernel/watch_queue.c", "function": "free_watch" }, "signature_version": "v1", "digest": { "length": 239.0, "function_hash": "313369638600437725296301508795684183997" }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@31824613a42aacdcbeb325bf07a1c8247a11ebe2" }, { "id": "CVE-2022-49256-da94fef9", "signature_type": "Line", "target": { "file": "kernel/watch_queue.c" }, "signature_version": "v1", "digest": { "line_hashes": [ "157250318527350411482311974135296965183", "52223220505761765810701734288128941816", "285002072406242075875667332690023495805", "250904878208422252973913682585705122372" ], "threshold": 0.9 }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@31824613a42aacdcbeb325bf07a1c8247a11ebe2" }, { "id": "CVE-2022-49256-e0152245", "signature_type": "Function", "target": { "file": "kernel/watch_queue.c", "function": "free_watch" }, "signature_version": "v1", "digest": { "length": 239.0, "function_hash": "313369638600437725296301508795684183997" }, "deprecated": false, "source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@7e8c9b0df07a77f0d072603b8ced2677e30e1893" } ] }