CVE-2022-50342
What it is
In the Linux kernel, the following vulnerability has been resolved: floppy: Fix memory leak in do_floppy_init() A memory leak was reported when floppy_alloc_disk() failed in do_floppy_init(). unreferenced object 0xffff888115ed25a0 (size 8): comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s) hex dump (first 8 bytes): 00 ac 67 5b 81 88 ff ff ..g[.... backtrace: [<000000007f457abb>] __kmalloc_node+0x4c/0xc0 [<00000000a87bfa9e>] blk_mq_realloc_tag_set_tags.part.0+0x6f/0x180 [<000000006f02e8b1>] blk_mq_alloc_tag_set+0x573/0x1130 [<0000000066007fd7>] 0xffffffffc06b8b08 [<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0 [<00000000e26d04ee>] do_init_module+0x1a4/0x680 [<000000001bb22407>] load_module+0x6249/0x7110 [<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200 [<000000007bddca46>] do_syscall_64+0x35/0x80 [<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 unreferenced object 0xffff88810fc30540 (size 32): comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000007f457abb>] __kmalloc_node+0x4c/0xc0 [<000000006b91eab4>] blk_mq_alloc_tag_set+0x393/0x1130 [<0000000066007fd7>] 0xffffffffc06b8b08 [<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0 [<00000000e26d04ee>] do_init_module+0x1a4/0x680 [<000000001bb22407>] load_module+0x6249/0x7110 [<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200 [<000000007bddca46>] do_syscall_64+0x35/0x80 [<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 If the floppy_alloc_disk() failed, disks of current drive will not be set, thus the lastest allocated set->tag cannot be freed in the error handling path. A simple call graph shown as below: floppy_module_init() floppy_init() do_floppy_init() for (drive = 0; drive < N_DRIVE; drive++) blk_mq_alloc_tag_set() blk_mq_alloc_tag_set_tags() blk_mq_realloc_tag_set_tags() # set->tag allocated floppy_alloc_disk() blk_mq_alloc_disk() # error occurred, disks failed to allocated ->out_put_disk: for (drive = 0; drive < N_DRIVE; drive++) if (!disks[drive][0]) # the last disks is not set and loop break break; blk_mq_free_tag_set() # the latest allocated set->tag leaked Fix this problem by free the set->tag of current drive before jump to error handling path. [efremov: added stable list, changed title]
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of 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
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-401
- Record status
- Modified
Affected
- Linux Kernel < 5.15.86
- Linux Kernel < 6.0.16
- Linux Kernel < 6.1.2
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-50342.md and follow it. Check whether this project is affected by CVE-2022-50342. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/55b3c66a0d441cd37154ae95e44d0b82ccfd580e
- https://git.kernel.org/stable/c/75d8c8851a4da0190c2480e84315b5fd3d0356c5
- https://git.kernel.org/stable/c/f36d8c8651506aea5f09899f5356ece5d1384f50
- https://git.kernel.org/stable/c/f8ace2e304c5dd8a7328db9cd2b8a4b1b98d83ec