UBUNTU-CVE-2025-37760
In the Linux kernel, the following vulnerability has been resolved: mm/vma: add give_up_on_oom option on modify/merge, use in uffd release Currently, if a VMA merge fails due to an OOM condition arising on commit merge or a failure to duplicate anon_vma's, we report this so the caller can handle it. However there are cases where the caller is only ostensibly trying a merge, and doesn't mind if it fails due to this condition. Since we do not want to introduce an implicit assumption that we only actually modify VMAs after OOM conditions might arise, add a 'give up on oom' option and make an explicit contract that, should this flag be set, we absolutely will not modify any VMAs should OOM arise and just bail out. Since it'd be very unusual for a user to try to vma_modify() with this flag set but be specifying a range within a VMA which ends up being split (which can fail due to rlimit issues, not only OOM), we add a debug warning for this condition. The motivating reason for this is uffd release - syzkaller (and Pedro Falcato's VERY astute analysis) found a way in which an injected fault on allocation, triggering an OOM condition on commit merge, would result in uffd code becoming confused and treating an error value as if it were a VMA pointer. To avoid this, we make use of this new VMG flag to ensure that this never occurs, utilising the fact that, should we be clearing entire VMAs, we do not wish an OOM event to be reported to us. Many thanks to Pedro Falcato for his excellent analysis and Jann Horn for his insightful and intelligent analysis of the situation, both of whom were instrumental in this fix.
02 / AFFECTED SOFTWARE
Affected packages
11 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
19 explicit affected versions
6 explicit affected versions
10 explicit affected versions
7 explicit affected versions
13 explicit affected versions
35 explicit affected versions
18 explicit affected versions
13 explicit affected versions
4 explicit affected versions
23 explicit affected versions
1 explicit affected versions
21 explicit affected versions
16 explicit affected versions
10 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
14 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
10 explicit affected versions
37 explicit affected versions
13 explicit affected versions
10 explicit affected versions
26 explicit affected versions
13 explicit affected versions
29 explicit affected versions
13 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
11 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
10 explicit affected versions
26 explicit affected versions
13 explicit affected versions
16 explicit affected versions
3 explicit affected versions
51 explicit affected versions
12 explicit affected versions
27 explicit affected versions
8 explicit affected versions
5 explicit affected versions
8 explicit affected versions
10 explicit affected versions
13 explicit affected versions
13 explicit affected versions
7 explicit affected versions
10 explicit affected versions
12 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
45 explicit affected versions
37 explicit affected versions
14 explicit affected versions
38 explicit affected versions
9 explicit affected versions
11 explicit affected versions
7 explicit affected versions
4 explicit affected versions
1 explicit affected versions
13 explicit affected versions
43 explicit affected versions
10 explicit affected versions
8 explicit affected versions
14 explicit affected versions
4 explicit affected versions
78 explicit affected versions
11 explicit affected versions
1 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: mm/vma: add give_up_on_oom option on modify/merge, use in uffd release Currently, if a VMA merge fails due to an OOM condition arising on commit merge or a failure to duplicate anon_vma's, we report this so the caller can handle it. However there are cases where the caller is only ostensibly trying a merge, and doesn't mind if it fails due to this condition. Since we do not want to introduce an implicit assumption that we only actually modify VMAs after OOM conditions might arise, add a 'give up on oom' option and make an explicit contract that, should this flag be set, we absolutely will not modify any VMAs should OOM arise and just bail out. Since it'd be very unusual for a user to try to vma_modify() with this flag set but be specifying a range within a VMA which ends up being split (which can fail due to rlimit issues, not only OOM), we add a debug warning for this condition. The motivating reason for this is uffd release - syzkaller (and Pedro Falcato's VERY astute analysis) found a way in which an injected fault on allocation, triggering an OOM condition on commit merge, would result in uffd code becoming confused and treating an error value as if it were a VMA pointer. To avoid this, we make use of this new VMG flag to ensure that this never occurs, utilising the fact that, should we be clearing entire VMAs, we do not wish an OOM event to be reported to us. Many thanks to Pedro Falcato for his excellent analysis and Jann Horn for his insightful and intelligent analysis of the situation, both of whom were instrumental in this fix.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/41e6ddcaa0f18dda4c3fadf22533775a30d6f72f
- https://git.kernel.org/stable/c/41e6ddcaa0f18dda4c3fadf22533775a30d6f72f
- https://git.kernel.org/stable/c/b906c1ad25adce6ff35be19b65a1aa7d960fe1d7
- https://git.kernel.org/stable/c/c103a75c61648203d731e3b97a6fbeea4003cb15
- https://ubuntu.com/security/CVE-2025-37760
- https://ubuntu.com/security/notices/USN-7594-1
- https://ubuntu.com/security/notices/USN-7594-2
- https://ubuntu.com/security/notices/USN-7594-3
- https://www.cve.org/CVERecord?id=CVE-2025-37760