Описание
In the Linux kernel, the following vulnerability has been resolved:
nfsd: clear opcnt on compound arg release to prevent OOB read
nfsd4_release_compoundargs() resets args->ops to the inline iops[8]
array when the dynamically-allocated ops buffer is freed, but leaves
args->opcnt at its original value (which can be up to 200 for NFSv4.1+
compounds).
If rq_status_counter is stuck at an odd value (which can happen when
nfsd_dispatch() hits an error path after setting it odd), the RPC
status dumpit handler reads min(opcnt, 16) entries from args->ops[].
Since iops only has 8 elements and is the last field in struct
nfsd4_compoundargs, reading indices 8-15 accesses adjacent slab memory
and leaks it to userspace via netlink.
Zero opcnt unconditionally in nfsd4_release_compoundargs() so stale
compound metadata is never exposed through the status interface.
[ cel: Remove the kvfree_rcu_mightsleep() sleep from the exposure window ]
A flaw was found in the Linux kernel's Network File System Daemon (nfsd) component. The nfsd4_release_compoundargs() function does not properly clear an internal counter (opcnt) when releasing a buffer. This oversight can lead to an out-of-bounds read, allowing an attacker to access adjacent memory and potentially leak sensitive information to userspace through netlink.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-8 | Affected | ||
| Red Hat OpenShift Container Platform 4 | openshift/ose-rhel-coreos-9 | Affected |
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Дополнительная информация
Статус:
EPSS
7.4 High
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: nfsd: clear opcnt on compound arg release to prevent OOB read nfsd4_release_compoundargs() resets args->ops to the inline iops[8] array when the dynamically-allocated ops buffer is freed, but leaves args->opcnt at its original value (which can be up to 200 for NFSv4.1+ compounds). If rq_status_counter is stuck at an odd value (which can happen when nfsd_dispatch() hits an error path after setting it odd), the RPC status dumpit handler reads min(opcnt, 16) entries from args->ops[]. Since iops only has 8 elements and is the last field in struct nfsd4_compoundargs, reading indices 8-15 accesses adjacent slab memory and leaks it to userspace via netlink. Zero opcnt unconditionally in nfsd4_release_compoundargs() so stale compound metadata is never exposed through the status interface. [ cel: Remove the kvfree_rcu_mightsleep() sleep from the exposure window ]
In the Linux kernel, the following vulnerability has been resolved: nfsd: clear opcnt on compound arg release to prevent OOB read nfsd4_release_compoundargs() resets args->ops to the inline iops[8] array when the dynamically-allocated ops buffer is freed, but leaves args->opcnt at its original value (which can be up to 200 for NFSv4.1+ compounds). If rq_status_counter is stuck at an odd value (which can happen when nfsd_dispatch() hits an error path after setting it odd), the RPC status dumpit handler reads min(opcnt, 16) entries from args->ops[]. Since iops only has 8 elements and is the last field in struct nfsd4_compoundargs, reading indices 8-15 accesses adjacent slab memory and leaks it to userspace via netlink. Zero opcnt unconditionally in nfsd4_release_compoundargs() so stale compound metadata is never exposed through the status interface. [ cel: Remove the kvfree_rcu_mightsleep() sleep from the exposure window ]
In the Linux kernel, the following vulnerability has been resolved: n ...
In the Linux kernel, the following vulnerability has been resolved: nfsd: clear opcnt on compound arg release to prevent OOB read nfsd4_release_compoundargs() resets args->ops to the inline iops[8] array when the dynamically-allocated ops buffer is freed, but leaves args->opcnt at its original value (which can be up to 200 for NFSv4.1+ compounds). If rq_status_counter is stuck at an odd value (which can happen when nfsd_dispatch() hits an error path after setting it odd), the RPC status dumpit handler reads min(opcnt, 16) entries from args->ops[]. Since iops only has 8 elements and is the last field in struct nfsd4_compoundargs, reading indices 8-15 accesses adjacent slab memory and leaks it to userspace via netlink. Zero opcnt unconditionally in nfsd4_release_compoundargs() so stale compound metadata is never exposed through the status interface. [ cel: Remove the kvfree_rcu_mightsleep() sleep from the exposure window ]
EPSS
7.4 High
CVSS3