CVE-2022-49779
What it is
In the Linux kernel, the following vulnerability has been resolved: kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case In __unregister_kprobe_top(), if the currently unregistered probe has post_handler but other child probes of the aggrprobe do not have post_handler, the post_handler of the aggrprobe is cleared. If this is a ftrace-based probe, there is a problem. In later calls to disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in __disarm_kprobe_ftrace() and may even cause use-after-free: Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2) WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0 Modules linked in: testKprobe_007(-) CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty #18 [...] Call Trace: <TASK> __disable_kprobe+0xcd/0xe0 __unregister_kprobe_top+0x12/0x150 ? mutex_lock+0xe/0x30 unregister_kprobes.part.23+0x31/0xa0 unregister_kprobe+0x32/0x40 __x64_sys_delete_module+0x15e/0x260 ? do_user_addr_fault+0x2cd/0x6b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] For the kprobe-on-ftrace case, we keep the post_handler setting to identify this aggrprobe armed with kprobe_ipmodify_ops. This way we can disarm it correctly.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Analyzed
Affected
- Linux Kernel < 5.4.225
- Linux Kernel < 5.10.156
- Linux Kernel < 5.15.80
- Linux Kernel < 6.0.10
- Linux Kernel 6.1
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Fix and advisories
- https://git.kernel.org/stable/c/55788ebbe8b365b4375bd56b4ba7db79d393a370
- https://git.kernel.org/stable/c/5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb
- https://git.kernel.org/stable/c/7b0007b28dd970176f2e297c06ae63eea2447127
- https://git.kernel.org/stable/c/7d606ae1abcc3eab5408e42444d789dc7def51b8
- https://git.kernel.org/stable/c/c49cc2c059b503e962c2f13a806c105f9b757df4
References
- https://git.kernel.org/stable/c/55788ebbe8b365b4375bd56b4ba7db79d393a370
- https://git.kernel.org/stable/c/5dd7caf0bdc5d0bae7cf9776b4d739fb09bd5ebb
- https://git.kernel.org/stable/c/7b0007b28dd970176f2e297c06ae63eea2447127
- https://git.kernel.org/stable/c/7d606ae1abcc3eab5408e42444d789dc7def51b8
- https://git.kernel.org/stable/c/c49cc2c059b503e962c2f13a806c105f9b757df4