CVE-2026-90140
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: cuse: wait for pending RCU callbacks on module exit Since commit 053fc4f755ad ("fuse: fix UAF in rcu pathwalks"), fuse_conn_put() frees the fuse_conn through call_rcu() rather than synchronously. For cuse, fc->release is cuse_fc_release(), which lives in the cuse module. If the module is removed before the RCU grace period ends, the callback jumps into freed module memory: userspace / module unload | RCU softirq ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ close(/dev/cuse) | cuse_channel_release() | fuse_dev_release() | fuse_conn_put(fch->conn) | call_rcu(delayed_release) ------+---> callback queued | rmmod cuse | cuse_exit() | cuse_channel_destroy() | ... | return | | <module text freed> | | rcu_do_batch() | delayed_release() | fc->release() | -> cuse_fc_release() | ^^^ freed text! The freed module text is unmapped by vfree(), so the jump into the stale callback triggers a page-fault Oops. If the virtual address is subsequently reused, the callback could execute unrelated code (undefined behaviour). Fix this by calling rcu_barrier() in cuse_exit() so that any pending fuse_conn release callback completes before the module is removed.
View original CVE JSON
{
"id": "CVE-2026-90140",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-17T17:17:06.710",
"lastModified": "2026-10-19T09:19:03.810",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncuse: wait for pending RCU callbacks on module exit\n\nSince commit 053fc4f755ad (\"fuse: fix UAF in rcu pathwalks\"),\nfuse_conn_put() frees the fuse_conn through call_rcu() rather than\nsynchronously. For cuse, fc->release is cuse_fc_release(), which\nlives in the cuse module. If the module is removed before the RCU\ngrace period ends, the callback jumps into freed module memory:\n\n userspace / module unload | RCU softirq\n~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n close(/dev/cuse) |\n cuse_channel_release() |\n fuse_dev_release() |\n fuse_conn_put(fch->conn) |\n call_rcu(delayed_release) ------+---> callback queued\n |\n rmmod cuse |\n cuse_exit() |\n cuse_channel_destroy() |\n ... |\n return |\n |\n <module text freed> |\n | rcu_do_batch()\n | delayed_release()\n | fc->release()\n | -> cuse_fc_release()\n | ^^^ freed text!\n\nThe freed module text is unmapped by vfree(), so the jump into the\nstale callback triggers a page-fault Oops. If the virtual address\nis subsequently reused, the callback could execute unrelated code\n(undefined behaviour).\n\nFix this by calling rcu_barrier() in cuse_exit() so that any pending\nfuse_conn release callback completes before the module is removed."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/fuse/cuse.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "bfbab62ca69f72bcd14ea30de1fb98f6080ad464",
"lessThan": "7fe415e1cd8fa875be263670c0ab47109818abb6",
"versionType": "git",
"status": "affected"
},
{
"version": "a8f650b93e55764ca9ff8e1ddebc151f57024086",
"lessThan": "45ae914b2f6ea56fc2f1c017fdee4e995bcb4c0e",
"versionType": "git",
"status": "affected"
},
{
"version": "535e9bd0e8f8d8cfdc29de7cdb902b5041427fe6",
"lessThan": "ac5c499413385cea3e0220d6050408d50842891d",
"versionType": "git",
"status": "affected"
},
{
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"versionType": "git",
"status": "affected"
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{
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"versionType": "git",
"status": "affected"
},
{
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"lessThan": "c40f3f24839f8404325a2099e26c2a04786ae309",
"versionType": "git",
"status": "affected"
},
{
"version": "053fc4f755ad43cf35210677bcba798ccdc48d0c",
"lessThan": "4deb3edead0c0e172cc7349e8855d741d3c5e162",
"versionType": "git",
"status": "affected"
},
{
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},
{
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"lessThan": "6.1.188",
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"status": "affected"
},
{
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"lessThan": "6.6.157",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/fuse/cuse.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.8",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.8",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.221",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.188",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.157",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.110",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.52",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.6",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/389bd349ddbcf90dbd8a4f2a4ab6e552d53df134",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/45ae914b2f6ea56fc2f1c017fdee4e995bcb4c0e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/c40f3f24839f8404325a2099e26c2a04786ae309",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}