CVE-2026-90107

Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: free pending qentry in smc_llc_flow_stop() before memset smc_llc_flow_stop() resets a flow struct with a blind memset: spin_lock_bh(&lgr->llc_flow_lock); memset(flow, 0, sizeof(*flow)); flow->type = SMC_LLC_FLOW_NONE; spin_unlock_bh(&lgr->llc_flow_lock); If flow->qentry is non-NULL at this point the pointer is overwritten without the allocation being freed, leaking one kmalloc object. A late-arriving duplicate CONFIRM_LINK or ADD_LINK_CONT message can set flow->qentry after the legitimate message has been consumed by the waiter via smc_llc_flow_qentry_clr() (which NULLs the pointer but leaves flow->type non-zero) but before the flow completes and smc_llc_flow_stop() runs. In that window the duplicate is stashed into flow->qentry, and then lost when smc_llc_flow_stop() zeros the struct. Call smc_llc_flow_qentry_del() inside the lock before the memset. smc_llc_flow_qentry_del() already checks flow->qentry before freeing, so the normal case where no entry is pending is a no-op.

Is your site exposed to CVE-2026-90107?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0021

Probability of exploitation

0.11%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/032aec7d03c9102616b98fea74f8f7145e7f867c https://git.kernel.org/stable/c/0879ea157acc1ac6752f6fcb755d1f91a2359238 https://git.kernel.org/stable/c/11bc373ee6630709f0c2da2e7860c23d503c9e9d https://git.kernel.org/stable/c/5ee0ceddc7785c6dcf4a8107fef01f0414a354f4 https://git.kernel.org/stable/c/5ff429dd6725fa6c1e17a4ed0be8ab675f67a98b https://git.kernel.org/stable/c/8e3deb150a5237b672c4579e69a6deb02027dbed https://git.kernel.org/stable/c/957dba2b8b5aebfe09caa6a6b22b958079082eab https://git.kernel.org/stable/c/f03aa5d36ae3c4068a1c3885146be99aa7fd9307

Frequently Asked Questions

What is CVE-2026-90107? +

In the Linux kernel, the following vulnerability has been resolved: net/smc: free pending qentry in smc_llc_flow_stop() before memset smc_llc_flow_stop() resets a flow struct with a blind memset: spin_lock_bh(&lgr->llc_flow_lock); memset(flow, 0, sizeof(*flow)); flow->type = SMC_LLC_FLOW_NONE; spin_unlock_bh(&lgr->llc_flow_lock); If flow->qentry is non-NULL at this point the pointer is overwritten without the allocation being freed, leaking one kmalloc object. A late-arriving duplicate CONFIRM_LINK or ADD_LINK_CONT message can set flow->qentry after the legitimate message has been consumed by the waiter via smc_llc_flow_qentry_clr() (which NULLs the pointer but leaves flow->type non-zero) but before the flow completes and smc_llc_flow_stop() runs. In that window the duplicate is stashed into flow->qentry, and then lost when smc_llc_flow_stop() zeros the struct. Call smc_llc_flow_qentry_del() inside the lock before the memset. smc_llc_flow_qentry_del() already checks flow->qentry before freeing, so the normal case where no entry is pending is a no-op.

How do I check if I'm vulnerable to CVE-2026-90107? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.