CVE-2022-50295: io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd()
In the Linux kernel, the following vulnerability has been resolved:
iouring/msgring: Fix NULL pointer dereference in iomsgsendfd()
Syzkaller produced the below call trace:
BUG: KASAN: null-ptr-deref in iomsgring+0x3cb/0x9f0 Write of size 8 at addr 0000000000000070 by task repro/16399
CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 Call Trace: <TASK> dumpstacklvl+0xcd/0x134 ? iomsgring+0x3cb/0x9f0 kasanreport+0xbc/0xf0 ? iomsgring+0x3cb/0x9f0 kasancheckrange+0x140/0x190 iomsgring+0x3cb/0x9f0 ? iomsgringprep+0x300/0x300 ioissuesqe+0x698/0xca0 iosubmitsqes+0x92f/0x1c30 dosysiouringenter+0xae4/0x24b0 .... RIP: 0033:0x7f2eaf8f8289 RSP: 002b:00007fff40939718 EFLAGS: 00000246 ORIGRAX: 00000000000001aa RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2eaf8f8289 RDX: 0000000000000000 RSI: 0000000000006f71 RDI: 0000000000000004 RBP: 00007fff409397a0 R08: 0000000000000000 R09: 0000000000000039 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004006d0 R13: 00007fff40939880 R14: 0000000000000000 R15: 0000000000000000 </TASK> Kernel panic - not syncing: paniconwarn set ...
We don't have a NULL check on fileptr in iomsgsendfd() function, so when fileptr is NUL srcfile is also NULL and getfile() dereferences a NULL pointer and leads to above crash.
Add a NULL check to fix this issue.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2022-50295?
CVE-2022-50295 is classified as having a high severity due to its potential for causing system instability.
How do I fix CVE-2022-50295?
The fix for CVE-2022-50295 involves upgrading to a patched version of the Linux kernel that resolves the NULL pointer dereference error.
What type of systems are affected by CVE-2022-50295?
CVE-2022-50295 affects systems running affected versions of the Linux kernel, particularly those utilizing io_uring functionality.
What are the risks associated with CVE-2022-50295?
The risks include potential system crashes or unexpected behavior due to the NULL pointer dereference during the operation of io_msg_send_fd.
When was CVE-2022-50295 reported?
CVE-2022-50295 was reported as a vulnerability in the Linux kernel, indicating the need for immediate attention and remediation.