mm/mremap: fix WARN with uffd that has remap events disabled
In the Linux kernel, the following vulnerability has been resolved: mm/mremap: fix WARN with uffd that has remap events disabled Registering userfaultd on a VMA that spans at least one PMD and then mremap()'ing that VMA can trigger a WARN when recovering from a failed page table move due to a page table allocation error. The code ends up doing the right thing (recurse, avoiding moving actual page tables), but triggering that WARN is unpleasant: WARNING: CPU: 2 PID: 6133 at mm/mremap.c:357 move_normal_pmd mm/mremap.c:357 [inline] WARNING: CPU: 2 PID: 6133 at mm/mremap.c:357 move_pgt_entry mm/mremap.c:595 [inline] WARNING: CPU: 2 PID: 6133 at mm/mremap.c:357 move_page_tables+0x3832/0x44a0 mm/mremap.c:852 Modules linked in: CPU: 2 UID: 0 PID: 6133 Comm: syz.0.19 Not tainted 6.17.0-rc1-syzkaller-00004-g53e760d89498 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:move_normal_pmd mm/mremap.c:357 [inline] RIP: 0010:move_pgt_entry mm/mremap.c:595 [inline] RIP: 0010:move_page_tables+0x3832/0x44a0 mm/mremap.c:852 Code: ... RSP: 0018:ffffc900037a76d8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000032930007 RCX: ffffffff820c6645 RDX: ffff88802e56a440 RSI: ffffffff820c7201 RDI: 0000000000000007 RBP: ffff888037728fc0 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000032930007 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc900037a79a8 R14: 0000000000000001 R15: dffffc0000000000 FS: 000055556316a50
CVE-2025-39775
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2025-39775
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "310ac886d68de661c3a334198d8604b722d7fdf8",
"lessThan": "1c15b4cd3a97aea013bdb18d9a55ca0384fbb8d4",
"versionType": "git"
},
{
"status": "affected",
"version": "0cef0bb836e3cfe00f08f9606c72abd72fe78ca3",
"lessThan": "d70ca21f7bff162a5afae1ddd6f4107adf05ae23",
"versionType": "git"
},
{
"status": "affected",
"version": "0cef0bb836e3cfe00f08f9606c72abd72fe78ca3",
"lessThan": "772e5b4a5e8360743645b9a466842d16092c4f94",
"versionType": "git"
},
{
"status": "affected",
"version": "8e2f6ba256dd1e590addc48e6e9577bf39c482f2",
"versionType": "git"
},
{
"status": "affected",
"version": "6.12.11",
"lessThan": "6.12.114",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.6.160",
"lessThan": "6.7",
"versionType": "semver"
}
],
"programFiles": [
"mm/mremap.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.114",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.16.4",
"versionType": "semver",
"lessThanOrEqual": "6.16.*"
},
{
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"mm/mremap.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2025-39775
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #46017 · Revision 1
- Added to Heist Feed
- Publisher date