cbcvebase.
CVE-2025-21709
published 2025-02-27

CVE-2025-21709: In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.20%
9.7th percentile
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through (at least) the rmap finding the vmas which have a pointer back to the mm_struct. Up to this point, there have been no issues with being able to find an mm_struct that was only partially initialised. Syzbot was able to make the incomplete mm_struct fail with recent forking changes, so it has been proven unsafe to use the mm_struct that hasn't been initialised, as referenced in the link below. Although 8ac662f5da19f ("fork: avoid inappropriate uprobe access to invalid mm") fixed the uprobe access, it does not completely remove the race. This patch sets the MMF_OOM_SKIP to avoid the iteration of the vmas on the oom side (even though this is extremely unlikely to be selected as an oom victim in the race window), and sets MMF_UNSTABLE to avoid other potential users from using a partially initialised mm_struct. When registering vmas for uprobe, skip the vmas in an mm that is marked unstable. Modifying a vma in an unstable mm may cause issues if the mm isn't fully initialised.

Affected

30 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.16.3-1 (forky)linux 6.16.3-1 (forky)
linuxlinux
linuxlinux>= d2406291483775ecddaee929231a39c70c08fda2 < 74c2471eb891a7dcb3874b21c106cda75f52be3074c2471eb891a7dcb3874b21c106cda75f52be30
linuxlinux>= d2406291483775ecddaee929231a39c70c08fda2 < da139948aeda677ac09cc0e7d837f8a314de7d55da139948aeda677ac09cc0e7d837f8a314de7d55
linuxlinux>= d2406291483775ecddaee929231a39c70c08fda2 < 64c37e134b120fb462fb4a80694bfb8e7be77b1464c37e134b120fb462fb4a80694bfb8e7be77b14
linuxlinux_kernel>= 0 < 6.16.3-16.16.3-1
linuxlinux_kernel>= 6.8 < 6.13.26.13.2
ubuntulinux
ubuntulinux-aws
ubuntulinux-azure
ubuntulinux-azure-6.8
ubuntulinux-azure-fde
ubuntulinux-azure-fde-6.8
ubuntulinux-azure-fips
ubuntulinux-fips
ubuntulinux-gcp
ubuntulinux-gcp-6.8
ubuntulinux-gcp-fips
ubuntulinux-gke
ubuntulinux-gkeop
ubuntulinux-hwe-6.8
ubuntulinux-lowlatency
ubuntulinux-lowlatency-hwe-6.8
ubuntulinux-nvidia
ubuntulinux-nvidia-6.8

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
vendor_ubuntu2.0LOW
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