Unrated severityNVD Advisory· Published Jan 20, 2025· Updated Nov 3, 2025
io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
CVE-2025-21655
Description
In the Linux kernel, the following vulnerability has been resolved:
io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
io_eventfd_do_signal() is invoked from an RCU callback, but when dropping the reference to the io_ev_fd, it calls io_eventfd_free() directly if the refcount drops to zero. This isn't correct, as any potential freeing of the io_ev_fd should be deferred another RCU grace period.
Just call io_eventfd_put() rather than open-code the dec-and-test and free, which will correctly defer it another RCU grace period.
Affected products
140- osv-coords138 versionspkg:deb/ubuntu/linux-lowlatency@6.11.0-1011.12?arch=source&distro=oracularpkg:deb/ubuntu/linux-raspi@6.11.0-1010.10?arch=source&distro=oracularpkg:rpm/almalinux/kernelpkg:rpm/almalinux/kernel-64kpkg:rpm/almalinux/kernel-64k-corepkg:rpm/almalinux/kernel-64k-debugpkg:rpm/almalinux/kernel-64k-debug-corepkg:rpm/almalinux/kernel-64k-debug-develpkg:rpm/almalinux/kernel-64k-debug-devel-matchedpkg:rpm/almalinux/kernel-64k-debug-modulespkg:rpm/almalinux/kernel-64k-debug-modules-corepkg:rpm/almalinux/kernel-64k-debug-modules-extrapkg:rpm/almalinux/kernel-64k-develpkg:rpm/almalinux/kernel-64k-devel-matchedpkg:rpm/almalinux/kernel-64k-modulespkg:rpm/almalinux/kernel-64k-modules-corepkg:rpm/almalinux/kernel-64k-modules-extrapkg:rpm/almalinux/kernel-abi-stablelistspkg:rpm/almalinux/kernel-corepkg:rpm/almalinux/kernel-cross-headerspkg:rpm/almalinux/kernel-debugpkg:rpm/almalinux/kernel-debug-corepkg:rpm/almalinux/kernel-debug-develpkg:rpm/almalinux/kernel-debug-devel-matchedpkg:rpm/almalinux/kernel-debug-modulespkg:rpm/almalinux/kernel-debug-modules-corepkg:rpm/almalinux/kernel-debug-modules-extrapkg:rpm/almalinux/kernel-debug-uki-virtpkg:rpm/almalinux/kernel-develpkg:rpm/almalinux/kernel-devel-matchedpkg:rpm/almalinux/kernel-docpkg:rpm/almalinux/kernel-headerspkg:rpm/almalinux/kernel-modulespkg:rpm/almalinux/kernel-modules-corepkg:rpm/almalinux/kernel-modules-extrapkg:rpm/almalinux/kernel-modules-extra-matchedpkg:rpm/almalinux/kernel-rtpkg:rpm/almalinux/kernel-rt-64kpkg:rpm/almalinux/kernel-rt-64k-corepkg:rpm/almalinux/kernel-rt-64k-debugpkg:rpm/almalinux/kernel-rt-64k-debug-corepkg:rpm/almalinux/kernel-rt-64k-debug-develpkg:rpm/almalinux/kernel-rt-64k-debug-modulespkg:rpm/almalinux/kernel-rt-64k-debug-modules-corepkg:rpm/almalinux/kernel-rt-64k-debug-modules-extrapkg:rpm/almalinux/kernel-rt-64k-develpkg:rpm/almalinux/kernel-rt-64k-modulespkg:rpm/almalinux/kernel-rt-64k-modules-corepkg:rpm/almalinux/kernel-rt-64k-modules-extrapkg:rpm/almalinux/kernel-rt-corepkg:rpm/almalinux/kernel-rt-debugpkg:rpm/almalinux/kernel-rt-debug-corepkg:rpm/almalinux/kernel-rt-debug-develpkg:rpm/almalinux/kernel-rt-debug-modulespkg:rpm/almalinux/kernel-rt-debug-modules-corepkg:rpm/almalinux/kernel-rt-debug-modules-extrapkg:rpm/almalinux/kernel-rt-develpkg:rpm/almalinux/kernel-rt-modulespkg:rpm/almalinux/kernel-rt-modules-corepkg:rpm/almalinux/kernel-rt-modules-extrapkg:rpm/almalinux/kernel-toolspkg:rpm/almalinux/kernel-tools-libspkg:rpm/almalinux/kernel-tools-libs-develpkg:rpm/almalinux/kernel-uki-virtpkg:rpm/almalinux/kernel-uki-virt-addonspkg:rpm/almalinux/kernel-zfcpdumppkg:rpm/almalinux/kernel-zfcpdump-corepkg:rpm/almalinux/kernel-zfcpdump-develpkg:rpm/almalinux/kernel-zfcpdump-devel-matchedpkg:rpm/almalinux/kernel-zfcpdump-modulespkg:rpm/almalinux/kernel-zfcpdump-modules-corepkg:rpm/almalinux/kernel-zfcpdump-modules-extrapkg:rpm/almalinux/libperfpkg:rpm/almalinux/perfpkg:rpm/almalinux/python3-perfpkg:rpm/almalinux/rtlapkg:rpm/almalinux/rvpkg:rpm/opensuse/dtb-aarch64&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-64kb&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-azure&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-debug&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-default-base&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-default&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-docs&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-kvmsmall&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-obs-build&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-obs-qa&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-rt_debug&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-rt&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-source-azure&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-source&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-source-rt&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-syms-azure&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-syms&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-syms-rt&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/kernel-zfcpdump&distro=openSUSE%20Leap%2015.6pkg:rpm/suse/kernel-64kb&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6pkg:rpm/suse/kernel-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6pkg:rpm/suse/kernel-coco_debug&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6pkg:rpm/suse/kernel-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-default-base&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20High%20Availability%20Extension%2015%20SP6pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Legacy%2015%20SP6pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Enterprise%20Workstation%20Extension%2015%20SP6pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-default&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-docs&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6pkg:rpm/suse/kernel-kvmsmall&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-kvmsmall&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-livepatch-MICRO-6-0-RT_Update_5&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-livepatch-MICRO-6-0-RT_Update_5&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-livepatch-MICRO-6-0_Update_5&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-livepatch-MICRO-6-0_Update_5&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-livepatch-SLE15-SP6-RT_Update_8&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6pkg:rpm/suse/kernel-livepatch-SLE15-SP6_Update_8&distro=SUSE%20Linux%20Enterprise%20Live%20Patching%2015%20SP6pkg:rpm/suse/kernel-obs-build&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6pkg:rpm/suse/kernel-rt_debug&distro=SUSE%20Real%20Time%20Module%2015%20SP6pkg:rpm/suse/kernel-rt&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-rt&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6pkg:rpm/suse/kernel-source-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6pkg:rpm/suse/kernel-source-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-source&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/kernel-source-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6pkg:rpm/suse/kernel-syms-azure&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Public%20Cloud%2015%20SP6pkg:rpm/suse/kernel-syms-coco&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Confidential%20Computing%20Technical%20Preview%2015%20SP6pkg:rpm/suse/kernel-syms&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP6pkg:rpm/suse/kernel-syms-rt&distro=SUSE%20Real%20Time%20Module%2015%20SP6pkg:rpm/suse/kernel-zfcpdump&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6
< 6.11.0-1011.12+ 137 more
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- (no CPE)range: < 1-1.1
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- (no CPE)range: < 1-1.2
- (no CPE)range: < 1-1.2
- (no CPE)range: < 1-150600.1.3.1
- (no CPE)range: < 1-150600.13.3.2
- (no CPE)range: < 6.4.0-150600.23.38.1
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- (no CPE)range: < 6.4.0-15061.15.coco15sp6.1
- (no CPE)range: < 6.4.0-150600.23.38.1
- (no CPE)range: < 6.4.0-150600.10.26.1
- (no CPE)range: < 6.4.0-150600.23.38.1
Patches
0No patches discovered yet.
Vulnerability mechanics
AI mechanics synthesis has not run for this CVE yet.
References
5- git.kernel.org/stable/c/6b63308c28987c6010b1180c72a6db4df6c68033mitre
- git.kernel.org/stable/c/8efff2aa2d95dc437ab67c5b4a9f1d3f367baa10mitre
- git.kernel.org/stable/c/a7085c3ae43b86d4b3d1b8275e6a67f14257e3b7mitre
- git.kernel.org/stable/c/c9a40292a44e78f71258b8522655bffaf5753bdbmitre
- project-zero.issues.chromium.org/issues/388499293mitre
News mentions
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