CVE-2022-48986: mm/gup: fix gup_pud_range() for dax
In the Linux kernel, the following vulnerability has been resolved:
mm/gup: fix guppudrange() for dax
For dax pud, pudhuge() returns true on x86. So the function works as long as hugetlb is configured. However, dax doesn't depend on hugetlb. Commit 414fd080d125 ("mm/gup: fix guppmdrange() for dax") fixed devmap-backed huge PMDs, but missed devmap-backed huge PUDs. Fix this as well.
This fixes the below kernel panic:
general protection fault, probably for non-canonical address 0x69e7c000cc478: 0000 [#1] SMP < snip > Call Trace: <TASK> getuserpagesfast+0x1f/0x40 iovitergetpages+0xc6/0x3b0 ? mempoolalloc+0x5d/0x170 bioiovitergetpages+0x82/0x4e0 ? bvecalloc+0x91/0xc0 ? bioallocbioset+0x19a/0x2a0 blkdevdirectIO+0x282/0x480 ? iocompleterwcommon+0xc0/0xc0 ? filemaprangehaspage+0x82/0xc0 genericfiledirectwrite+0x9d/0x1a0 ? inodeupdatetime+0x24/0x30 genericfilewriteiter+0xbd/0x1e0 blkdevwriteiter+0xb4/0x150 ? ioimportiovec+0x8d/0x340 iowrite+0xf9/0x300 ioissuesqe+0x3c3/0x1d30 ? sysvecrescheduleipi+0x6c/0x80 ioqueuesqe+0x33/0x240 ? fget+0x76/0xa0 iosubmitsqes+0xe6a/0x18d0 ? fgetlight+0xd1/0x100 x64sysiouringenter+0x199/0x880 ? contexttrackingenter+0x1f/0x70 ? irqentryexittousermode+0x24/0x30 ? irqentryexit+0x1d/0x30 ? contexttrackingexit+0xe/0x70 dosyscall64+0x3b/0x90 entrySYSCALL64afterhwframe+0x61/0xcb RIP: 0033:0x7fc97c11a7be < snip > </TASK> ---[ end trace 48b2e0e67debcaeb ]--- RIP: 0010:internalgetuserpagesfast+0x340/0x990 < snip > Kernel panic - not syncing: Fatal exception Kernel Offset: disabled
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch 414fd080d125
Event History
Frequently Asked Questions
What is the severity of CVE-2022-48986?
CVE-2022-48986 has been rated as having moderate severity due to its potential impact on memory management in the Linux kernel.
How do I fix CVE-2022-48986?
To fix CVE-2022-48986, you should upgrade to a patched version of the Linux kernel that resolves this vulnerability.
Which Linux kernel versions are affected by CVE-2022-48986?
CVE-2022-48986 affects multiple versions of the Linux kernel, specifically those between 4.9.165 and 6.1-rc8.
What type of vulnerability is CVE-2022-48986?
CVE-2022-48986 is a memory management vulnerability related to the get_user_pages function in the Linux kernel.
Is there a public announcement for CVE-2022-48986?
Yes, CVE-2022-48986 has been publicly documented in Linux kernel mailing lists and security advisories.