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[PATCH OLK-6.6 00/12] KVM: arm64: Add support for vTLBID
by Jinqian Yang 16 Sep '26

16 Sep '26

This series adds KVM virtualization for TLBID so that a guest can use the feature. KVM maintains a vDomain-to-pDomain mapping and writes it into VTLBID(n) on vCPU load; the hardware then translates the guest's vDomain id into the corresponding pDomain id for TLBI broadcast. The series covers: - TLBID-related sysreg definitions (TLBIDIDR_EL1, VTLBIDn_EL2, HCRX_EL2). - KVM internal helpers for TLBID virtualization init/teardown and vDomain configuration. - VTLBID(n) map update on vCPU load/migration, with ioctls for QEMU to query max vDomains and set per-vCPU vDomain bitmaps. - Guest exposure of TLBIDIDR_EL1 and ID_AA64MMFR4_EL1.TLBID, with trap handling. - Optimizations: pCPU-to-vCPU reverse index to avoid vCPU traversal, skipping TLB flush/IPI when the domain map is unchanged, and a tracepoint to replace trace_printk. Jinqian Yang (10): KVM: arm64: Add internal helpers to support TLBID virtualization KVM: arm64: Update VTLBID(n) when vCPU load KVM: arm64: Add ioctls to support TLBID virtualzation KVM: arm64: Ensure DVMBM is disabled when TLBID is enabled KVM: arm64: Expose tlbididr_el1 to guest KVM: arm64: Expose ID_AA64MMFR4_EL1_TLBID to guest KVM: arm64: Enable read TLBIDIDR_EL1 trap in guest KVM: arm64: Use pCPU-to-vCPU reverse index to avoid vCPU traversal KVM: arm64: Skip TLB invalidation and vCPU IPI when domain map is unchanged KVM: arm64: Replace trace_printk with tracepoint in kvm_tlbidomain_vcpu_load Tian Zheng (1): KVM: arm64: Skip VM-level ID_AA64MMFR4 write on vCPU hotplug Zhou Wang (1): arm64/sysreg: Add TLBID sysreg Documentation/virt/kvm/api.rst | 62 ++++ arch/arm64/include/asm/kvm_host.h | 45 +++ arch/arm64/include/uapi/asm/kvm.h | 2 + arch/arm64/kvm/arm.c | 453 ++++++++++++++++++++++++++- arch/arm64/kvm/hisilicon/hisi_virt.c | 9 + arch/arm64/kvm/sys_regs.c | 67 +++- arch/arm64/kvm/sys_regs.h | 2 + arch/arm64/kvm/trace_arm.h | 47 +++ arch/arm64/tools/sysreg | 24 +- include/uapi/linux/kvm.h | 14 + 10 files changed, 721 insertions(+), 4 deletions(-) -- 2.33.0

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[PATCH OLK-6.6 00/19] backport minios part4 patches from linux mainline on September 16th.
by Qinxin Xia 16 Sep '26

16 Sep '26

driver inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8904 ---------------------------------------------------------------------- backport minios part4 patches from linux mainline on September 16th. Marc Zyngier (2): KVM: arm64: Properly save/restore HCRX_EL2 KVM: arm64: Kill HCRX_HOST_FLAGS Mark Brown (6): arm64/sysreg: Update HCRX_EL2 definition for DDI0601 2023-09 arm64/fpsimd: Enable host kernel access to FPMR arm64/fpsimd: Support FEAT_FPMR arm64/signal: Add FPMR signal handling arm64/ptrace: Expose FPMR via ptrace arm64/fpsimd: Don't corrupt FPMR when streaming mode changes Mark Rutland (10): arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR arm64/fpsimd: Add fpsimd_save_and_flush_current_state() arm64/fpsimd: Reset FPMR upon exec() arm64/fpsimd: signal32: Always save+flush state early arm64/fpsimd: signal: Always save+flush state early arm64/fpsimd: Avoid warning when sve_to_fpsimd() is unused arm64/fpsimd: Do not discard modified SVE state arm64/fpsimd: signal: Clear TPIDR2 when delivering signals arm64/fpsimd: signal: Use SMSTOP behaviour in setup_return() arm64/fpsimd: Add task_smstop_sm() Qinxin Xia (1): arm64/idreg: Add support "arm64.nocnp" for start option Documentation/arch/arm64/sme.rst | 2 +- arch/arm64/include/asm/cpufeature.h | 6 ++ arch/arm64/include/asm/el2_setup.h | 2 +- arch/arm64/include/asm/fpsimd.h | 9 +- arch/arm64/include/asm/kvm_arm.h | 1 - arch/arm64/include/asm/kvm_kabi.h | 18 ++++ arch/arm64/include/asm/processor.h | 2 +- arch/arm64/include/asm/signal_common.h | 20 +++- arch/arm64/include/uapi/asm/sigcontext.h | 8 ++ arch/arm64/kernel/cpufeature.c | 15 ++- arch/arm64/kernel/entry-common.c | 50 +++++++--- arch/arm64/kernel/fpsimd.c | 99 +++++++++++++------- arch/arm64/kernel/idreg-override.c | 11 +++ arch/arm64/kernel/ptrace.c | 46 +++++++++ arch/arm64/kernel/signal.c | 114 +++++++++++------------ arch/arm64/kernel/signal32.c | 11 ++- arch/arm64/kvm/arm.c | 3 +- arch/arm64/kvm/fpsimd.c | 2 + arch/arm64/kvm/hyp/include/hyp/switch.h | 13 ++- arch/arm64/tools/cpucaps | 2 +- arch/arm64/tools/sysreg | 4 +- include/uapi/linux/elf.h | 1 + 22 files changed, 308 insertions(+), 131 deletions(-) create mode 100644 arch/arm64/include/asm/kvm_kabi.h -- 2.33.0

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[PATCH openEuler-1.0-LTS] ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock
by Chen Yuxi 16 Sep '26

16 Sep '26

From: Xiubo Li <xiubo.li(a)clyso.com> mainline inclusion from mainline-v7.3-rc1 commit 7af4c4f01305b0935adf6d4301b1ec407025485d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19017 CVE: CVE-2026-89655 Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/comm… -------------------------------- list_for_each_entry() iterates ci->i_cap_flush_list but drops i_ceph_lock to send cap messages. During the unlock window, handle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries with tid <= flush_tid from the list, release i_ceph_lock, and free them via ceph_free_cap_flush() outside any lock. When the original thread reacquires i_ceph_lock and the for-loop macro advances via cf = list_next_entry(cf, i_list), it dereferences cf->i_list.next on freed memory. The race timeline: __kick_flushing_caps() handle_cap_flush_ack() ----------------------- ----------------------- holds i_ceph_lock <--- iterates to cf (tid=10) prepares FLUSH message drops i_ceph_lock <--- __send_cap() ── FLUSH(tid=10) MDS sends FLUSH_ACK(tid=10) ---> acquires i_ceph_lock cf->tid(10) <= flush_tid(10), detaches cf from i_cap_flush_list drops i_ceph_lock ceph_free_cap_flush(cf) <- frees it! acquires i_ceph_lock <--- for-loop advances: cf = list_next_entry(cf, i_list) -- UAF on freed cf->i_list.next The cf was just sent by __kick_flushing_caps itself via __send_cap(). The MDS may respond with FLUSH_ACK quickly enough that handle_cap_flush_ack() frees cf before __kick_flushing_caps can finish the iteration. Fix by converting to a manual while loop: save the next pointer under i_ceph_lock before dropping it, then use the saved pointer after reacquiring, so the potentially-freed cf is never accessed again. Cc: stable(a)vger.kernel.org Signed-off-by: Xiubo Li <xiubo.li(a)clyso.com> Reviewed-by: Viacheslav Dubeyko <slava(a)dubeyko.com> Signed-off-by: Ilya Dryomov <idryomov(a)gmail.com> Signed-off-by: Chen Yuxi <chenyuxi19(a)huawei.com> --- fs/ceph/caps.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 80591f37dd77..a89ca4d01f91 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2303,9 +2303,14 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, int ret; u64 first_tid = 0; - list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) { - if (cf->tid < first_tid) + cf = list_first_entry(&ci->i_cap_flush_list, struct ceph_cap_flush, i_list); + while (&cf->i_list != &ci->i_cap_flush_list) { + struct ceph_cap_flush *next; + + if (cf->tid < first_tid) { + cf = list_next_entry(cf, i_list); continue; + } cap = ci->i_auth_cap; if (!(cap && cap->session == session)) { @@ -2315,6 +2320,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } first_tid = cf->tid + 1; + next = list_next_entry(cf, i_list); if (cf->caps) { dout("kick_flushing_caps %p cap %p tid %llu %s\n", @@ -2357,6 +2363,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } spin_lock(&ci->i_ceph_lock); + cf = next; } } -- 2.34.1

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[PATCH OLK-5.10] ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock
by Chen Yuxi 16 Sep '26

16 Sep '26

From: Xiubo Li <xiubo.li(a)clyso.com> mainline inclusion from mainline-v7.3-rc1 commit 7af4c4f01305b0935adf6d4301b1ec407025485d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19017 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- list_for_each_entry() iterates ci->i_cap_flush_list but drops i_ceph_lock to send cap messages. During the unlock window, handle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries with tid <= flush_tid from the list, release i_ceph_lock, and free them via ceph_free_cap_flush() outside any lock. When the original thread reacquires i_ceph_lock and the for-loop macro advances via cf = list_next_entry(cf, i_list), it dereferences cf->i_list.next on freed memory. The race timeline: __kick_flushing_caps() handle_cap_flush_ack() ----------------------- ----------------------- holds i_ceph_lock <--- iterates to cf (tid=10) prepares FLUSH message drops i_ceph_lock <--- __send_cap() ── FLUSH(tid=10) MDS sends FLUSH_ACK(tid=10) ---> acquires i_ceph_lock cf->tid(10) <= flush_tid(10), detaches cf from i_cap_flush_list drops i_ceph_lock ceph_free_cap_flush(cf) <- frees it! acquires i_ceph_lock <--- for-loop advances: cf = list_next_entry(cf, i_list) -- UAF on freed cf->i_list.next The cf was just sent by __kick_flushing_caps itself via __send_cap(). The MDS may respond with FLUSH_ACK quickly enough that handle_cap_flush_ack() frees cf before __kick_flushing_caps can finish the iteration. Fix by converting to a manual while loop: save the next pointer under i_ceph_lock before dropping it, then use the saved pointer after reacquiring, so the potentially-freed cf is never accessed again. Cc: stable(a)vger.kernel.org Signed-off-by: Xiubo Li <xiubo.li(a)clyso.com> Reviewed-by: Viacheslav Dubeyko <slava(a)dubeyko.com> Signed-off-by: Ilya Dryomov <idryomov(a)gmail.com> Signed-off-by: Chen Yuxi <chenyuxi19(a)huawei.com> --- fs/ceph/caps.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 9bebdafd5ec9..d709edea84ae 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2513,9 +2513,14 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } } - list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) { - if (cf->tid < first_tid) + cf = list_first_entry(&ci->i_cap_flush_list, struct ceph_cap_flush, i_list); + while (&cf->i_list != &ci->i_cap_flush_list) { + struct ceph_cap_flush *next; + + if (cf->tid < first_tid) { + cf = list_next_entry(cf, i_list); continue; + } cap = ci->i_auth_cap; if (!(cap && cap->session == session)) { @@ -2525,6 +2530,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } first_tid = cf->tid + 1; + next = list_next_entry(cf, i_list); if (!cf->is_capsnap) { struct cap_msg_args arg; @@ -2565,6 +2571,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } spin_lock(&ci->i_ceph_lock); + cf = next; } } -- 2.34.1

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[PATCH OLK-6.6] ceph: fix UAF in __kick_flushing_caps() on cf entry freed during unlock
by Chen Yuxi 16 Sep '26

16 Sep '26

From: Xiubo Li <xiubo.li(a)clyso.com> mainline inclusion from mainline-v7.3-rc1 commit 7af4c4f01305b0935adf6d4301b1ec407025485d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19017 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- list_for_each_entry() iterates ci->i_cap_flush_list but drops i_ceph_lock to send cap messages. During the unlock window, handle_cap_flush_ack() can acquire i_ceph_lock, detach cf entries with tid <= flush_tid from the list, release i_ceph_lock, and free them via ceph_free_cap_flush() outside any lock. When the original thread reacquires i_ceph_lock and the for-loop macro advances via cf = list_next_entry(cf, i_list), it dereferences cf->i_list.next on freed memory. The race timeline: __kick_flushing_caps() handle_cap_flush_ack() ----------------------- ----------------------- holds i_ceph_lock <--- iterates to cf (tid=10) prepares FLUSH message drops i_ceph_lock <--- __send_cap() ── FLUSH(tid=10) MDS sends FLUSH_ACK(tid=10) ---> acquires i_ceph_lock cf->tid(10) <= flush_tid(10), detaches cf from i_cap_flush_list drops i_ceph_lock ceph_free_cap_flush(cf) <- frees it! acquires i_ceph_lock <--- for-loop advances: cf = list_next_entry(cf, i_list) -- UAF on freed cf->i_list.next The cf was just sent by __kick_flushing_caps itself via __send_cap(). The MDS may respond with FLUSH_ACK quickly enough that handle_cap_flush_ack() frees cf before __kick_flushing_caps can finish the iteration. Fix by converting to a manual while loop: save the next pointer under i_ceph_lock before dropping it, then use the saved pointer after reacquiring, so the potentially-freed cf is never accessed again. Cc: stable(a)vger.kernel.org Signed-off-by: Xiubo Li <xiubo.li(a)clyso.com> Reviewed-by: Viacheslav Dubeyko <slava(a)dubeyko.com> Signed-off-by: Ilya Dryomov <idryomov(a)gmail.com> Signed-off-by: Chen Yuxi <chenyuxi19(a)huawei.com> --- fs/ceph/caps.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 0ff68e63f5a6..c80a17f82f81 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2534,9 +2534,14 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } } - list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) { - if (cf->tid < first_tid) + cf = list_first_entry(&ci->i_cap_flush_list, struct ceph_cap_flush, i_list); + while (&cf->i_list != &ci->i_cap_flush_list) { + struct ceph_cap_flush *next; + + if (cf->tid < first_tid) { + cf = list_next_entry(cf, i_list); continue; + } cap = ci->i_auth_cap; if (!(cap && cap->session == session)) { @@ -2546,6 +2551,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } first_tid = cf->tid + 1; + next = list_next_entry(cf, i_list); if (!cf->is_capsnap) { struct cap_msg_args arg; @@ -2586,6 +2592,7 @@ static void __kick_flushing_caps(struct ceph_mds_client *mdsc, } spin_lock(&ci->i_ceph_lock); + cf = next; } } -- 2.34.1

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[PATCH OLK-6.6] mm: fix double initialization race in mm_counter_try_switch_to_pcpu
by Jinjiang Tu 16 Sep '26

16 Sep '26

hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9960 ---------------------------------------- When CONFIG_MM_COUNTER_ATOMIC is enabled, mm counters start in atomic mode (using count_atomic) for single-threaded processes and switch to percpu mode (using count) upon the first CLONE_THREAD. The switch is performed by mm_counter_try_switch_to_pcpu(), which calls percpu_counter_switch_to_pcpu_many() without any lock protection. If the first switch attempt fails (GFP_ATOMIC allocation failure under memory pressure), the mm remains in atomic mode while the process is now multi-threaded. Subsequent CLONE_THREAD calls from two threads can race into mm_counter_try_switch_to_pcpu() simultaneously: Thread A (CLONE_THREAD) Thread B (CLONE_THREAD) ------------------------- ------------------------- percpu_counter_switch_to_pcpu_many percpu_counter_switch_to_pcpu_many percpu_counter_initialized? false percpu_counter_initialized? false __percpu_counter_init_many __percpu_counter_init_many alloc counters (1st) alloc counters (2nd, leaked) fbc[i].counters = ptr1 fbc[i].counters = ptr2 (overwrite) list_add(&fbc[i].list) list_add(&fbc[i].list) (double add) Both threads pass the percpu_counter_initialized() check before either completes __percpu_counter_init_many(), leading to: - Double percpu memory allocation (first allocation leaked) - Concurrent re-init of fbc[i].lock - Same fbc[i].list node added twice to the global percpu_counters list, corrupting the list and potentially triggering a list_add BUG() Fix this by serializing the switch with mm->arg_lock. This ensures the check-then-init sequence in percpu_counter_switch_to_pcpu_many() is atomic across concurrent CLONE_THREAD callers: if the first caller succeeds, the second observes counters != NULL and returns early; if the first fails, the second retries safely without overlap. Fixes: 46213033b804 ("mm: add config option for atomic mode in mm counter") Signed-off-by: Jinjiang Tu <tujinjiang(a)huawei.com> --- include/linux/mm.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5fc9092ea039..dd84843c3029 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2793,10 +2793,16 @@ static inline s64 get_mm_counter_sum(struct mm_struct *mm, int member) static inline int mm_counter_try_switch_to_pcpu(struct mm_struct *mm) { + int ret; + if (!mm_counter_is_atomic()) return 0; - return percpu_counter_switch_to_pcpu_many(mm->rss_stat, NR_MM_COUNTERS); + spin_lock(&mm->arg_lock); + ret = percpu_counter_switch_to_pcpu_many(mm->rss_stat, NR_MM_COUNTERS); + spin_unlock(&mm->arg_lock); + + return ret; } static inline int mm_counter_init(struct mm_struct *mm) -- 2.43.0

2 1

[PATCH 01/19] arm64/sysreg: Update HCRX_EL2 definition for DDI0601 2023-09
by Qinxin Xia 16 Sep '26

16 Sep '26

From: Mark Brown <broonie(a)kernel.org> mainline inclusion from mainline-6.8 commit 126cb3a60d35cc2ce7db090b087e00ff85b12cfc category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/8904 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… ---------------------------------------------------------------------- DDI0601 2023-09 defines new fields in HCRX_EL2 controlling access to new system registers, update our definition of HCRX_EL2 to reflect this. Signed-off-by: Mark Brown <broonie(a)kernel.org> Reviewed-by: Fuad Tabba <tabba(a)google.com> Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-11-45284e53… Signed-off-by: Will Deacon <will(a)kernel.org> Signed-off-by: Qinxin Xia <xiaqinxin(a)huawei.com> Signed-off-by: Hongye Lin <linhongye(a)h-partners.com> --- arch/arm64/tools/sysreg | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg index 4067136b8863..603456d5e469 100644 --- a/arch/arm64/tools/sysreg +++ b/arch/arm64/tools/sysreg @@ -3124,7 +3124,9 @@ Fields ZCR_ELx EndSysreg Sysreg HCRX_EL2 3 4 1 2 2 -Res0 63:23 +Res0 63:25 +Field 24 PACMEn +Field 23 EnFPM Field 22 GCSEn Field 21 EnIDCP128 Field 20 EnSDERR -- 2.33.0

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[PATCH OLK-6.6] iommufd: Fix race during abort for file descriptors
by Zhang Yuwei 15 Sep '26

15 Sep '26

mainline inclusion from mainline-v6.17-rc1 commit 4e034bf045b12852a24d5d33f2451850818ba0c1 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/7960 CVE: CVE-2025-39966 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- fput() doesn't actually call file_operations release() synchronously, it puts the file on a work queue and it will be released eventually. This is normally fine, except for iommufd the file and the iommufd_object are tied to gether. The file has the object as it's private_data and holds a users refcount, while the object is expected to remain alive as long as the file is. When the allocation of a new object aborts before installing the file it will fput() the file and then go on to immediately kfree() the obj. This causes a UAF once the workqueue completes the fput() and tries to decrement the users refcount. Fix this by putting the core code in charge of the file lifetime, and call __fput_sync() during abort to ensure that release() is called before kfree. __fput_sync() is a bit too tricky to open code in all the object implementations. Instead the objects tell the core code where the file pointer is and the core will take care of the life cycle. Adapted from upstream commit 4e034bf045b1 ("iommufd: Fix race during abort for file descriptors"). Differences vs upstream: - No eventq.c/veventq/hw_queue in this tree; the eventq hunks fall to fault.c iommufd_fault_alloc() error paths directly. - struct iommufd_fault holds obj/filep directly (no common substruct). - No pre_destroy member in struct iommufd_object_ops. Link: https://patch.msgid.link/r/1-v1-02cd136829df+31-iommufd_syz_fput_jgg@nvidia… Cc: stable(a)vger.kernel.org Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object") Reviewed-by: Nicolin Chen <nicolinc(a)nvidia.com> Reviewed-by: Nirmoy Das <nirmoyd(a)nvidia.com> Reviewed-by: Kevin Tian <kevin.tian(a)intel.com> Tested-by: Nicolin Chen <nicolinc(a)nvidia.com> Reported-by: syzbot+80620e2d0d0a33b09f93(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/68c8583d.050a0220.2ff435.03a2.GAE@google.com Signed-off-by: Jason Gunthorpe <jgg(a)nvidia.com> Conflicts: drivers/iommu/iommufd/eventq.c drivers/iommu/iommufd/main.c [context conflict] Signed-off-by: Zhang Yuwei <zhangyuwei20(a)huawei.com> --- drivers/iommu/iommufd/fault.c | 5 ++--- drivers/iommu/iommufd/main.c | 34 +++++++++++++++++++++++++++++++--- 2 files changed, 33 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c index b6a669d06110..8c41c49be2c6 100644 --- a/drivers/iommu/iommufd/fault.c +++ b/drivers/iommu/iommufd/fault.c @@ -401,6 +401,7 @@ int iommufd_fault_alloc(struct iommufd_ucmd *ucmd) mutex_init(&fault->mutex); init_waitqueue_head(&fault->wait_queue); + /* The filep is fput() by the core code during failure */ filep = anon_inode_getfile("[iommufd-pgfault]", &iommufd_fault_fops, fault, O_RDWR); if (IS_ERR(filep)) { @@ -415,7 +416,7 @@ int iommufd_fault_alloc(struct iommufd_ucmd *ucmd) fdno = get_unused_fd_flags(O_CLOEXEC); if (fdno < 0) { rc = fdno; - goto out_fput; + goto out_abort; } cmd->out_fault_id = fault->obj.id; @@ -431,8 +432,6 @@ int iommufd_fault_alloc(struct iommufd_ucmd *ucmd) return 0; out_put_fdno: put_unused_fd(fdno); -out_fput: - fput(filep); out_abort: iommufd_object_abort_and_destroy(ucmd->ictx, &fault->obj); diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index dc5353e30ac2..35f570875f65 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -23,6 +23,7 @@ #include "iommufd_test.h" struct iommufd_object_ops { + size_t file_offset; void (*destroy)(struct iommufd_object *obj); void (*abort)(struct iommufd_object *obj); }; @@ -71,10 +72,30 @@ void iommufd_object_abort(struct iommufd_ctx *ictx, struct iommufd_object *obj) void iommufd_object_abort_and_destroy(struct iommufd_ctx *ictx, struct iommufd_object *obj) { - if (iommufd_object_ops[obj->type].abort) - iommufd_object_ops[obj->type].abort(obj); + const struct iommufd_object_ops *ops = &iommufd_object_ops[obj->type]; + + if (ops->file_offset) { + struct file **filep = ((void *)obj) + ops->file_offset; + + /* + * A file should hold a users refcount while the file is open + * and put it back in its release. The file should hold a + * pointer to obj in their private data. Normal fput() is + * deferred to a workqueue and can get out of order with the + * following kfree(obj). Using the sync version ensures the + * release happens immediately. During abort we require the file + * refcount is one at this point - meaning the object alloc + * function cannot do anything to allow another thread to take a + * refcount prior to a guaranteed success. + */ + if (*filep) + __fput_sync(*filep); + } + + if (ops->abort) + ops->abort(obj); else - iommufd_object_ops[obj->type].destroy(obj); + ops->destroy(obj); iommufd_object_abort(ictx, obj); } @@ -497,6 +518,12 @@ void iommufd_ctx_set_kvm(struct iommufd_ctx *ictx, struct kvm *kvm) } EXPORT_SYMBOL_NS_GPL(iommufd_ctx_set_kvm, IOMMUFD); +#define IOMMUFD_FILE_OFFSET(_struct, _filep, _obj) \ + .file_offset = (offsetof(_struct, _filep) + \ + BUILD_BUG_ON_ZERO(!__same_type( \ + struct file *, ((_struct *)NULL)->_filep)) + \ + BUILD_BUG_ON_ZERO(offsetof(_struct, _obj))) + static const struct iommufd_object_ops iommufd_object_ops[] = { [IOMMUFD_OBJ_ACCESS] = { .destroy = iommufd_access_destroy_object, @@ -517,6 +544,7 @@ static const struct iommufd_object_ops iommufd_object_ops[] = { }, [IOMMUFD_OBJ_FAULT] = { .destroy = iommufd_fault_destroy, + IOMMUFD_FILE_OFFSET(struct iommufd_fault, filep, obj), }, [IOMMUFD_OBJ_VIOMMU] = { .destroy = iommufd_viommu_destroy, -- 2.22.0

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[PATCH OLK-5.10] net: usb: rtl8150: fix use-after-free in rtl8150_start_xmit()
by Zhang Qilong 15 Sep '26

15 Sep '26

From: Zhan Jun <zhanjun(a)uniontech.com> stable inclusion from stable-v5.10.258 commit 5af290c86fa81ddbc86a08d54229af5daa40c6a4 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15684 CVE: CVE-2026-52982 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 23f0e34c64acba15cad4d23e50f41f533da195fa ] syzbot reported a KASAN slab-use-after-free read in rtl8150_start_xmit() when accessing skb->len for tx statistics after usb_submit_urb() has been called: BUG: KASAN: slab-use-after-free in rtl8150_start_xmit+0x71f/0x760 drivers/net/usb/rtl8150.c:712 Read of size 4 at addr ffff88810eb7a930 by task kworker/0:4/5226 The URB completion handler write_bulk_callback() frees the skb via dev_kfree_skb_irq(dev->tx_skb). The URB may complete on another CPU in softirq context before usb_submit_urb() returns in the submitter, so by the time the submitter reads skb->len the skb has already been queued to the per-CPU completion_queue and freed by net_tx_action(): CPU A (xmit) CPU B (USB completion softirq) ------------ ------------------------------ dev->tx_skb = skb; usb_submit_urb() --+ |-------> write_bulk_callback() | dev_kfree_skb_irq(dev->tx_skb) | net_tx_action() | napi_skb_cache_put() <-- free netdev->stats.tx_bytes | += skb->len; <-- UAF read Fix it by caching skb->len before submitting the URB and using the cached value when updating the tx_bytes counter. The pre-existing tx_bytes semantics are preserved: the counter tracks the original frame length (skb->len), not the ETH_ZLEN/USB-alignment padded "count" value that is handed to the device. Changing that would be a user-visible accounting change and is out of scope for this UAF fix. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+3f46c095ac0ca048cb71(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69e69ee7.050a0220.24bfd3.002b.GAE@google.com/ Closes: https://syzkaller.appspot.com/bug?extid=3f46c095ac0ca048cb71 Reviewed-by: Andrew Lunn <andrew(a)lunn.ch> Signed-off-by: Zhan Jun <zhanjun(a)uniontech.com> Link: https://patch.msgid.link/809895186B866C10+20260423004913.136655-1-zhangdand… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: drivers/net/usb/rtl8150.c [Just context confilcts] Signed-off-by: Zhang Qilong <zhangqilong3(a)huawei.com> --- drivers/net/usb/rtl8150.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c index bf8a60533f3e..7b775cd89f4a 100644 --- a/drivers/net/usb/rtl8150.c +++ b/drivers/net/usb/rtl8150.c @@ -675,12 +675,15 @@ static void rtl8150_set_multicast(struct net_device *netdev) static netdev_tx_t rtl8150_start_xmit(struct sk_buff *skb, struct net_device *netdev) { rtl8150_t *dev = netdev_priv(netdev); + unsigned int skb_len; int count, res; + skb_len = skb->len; + netif_stop_queue(netdev); count = (skb->len < 60) ? 60 : skb->len; count = (count & 0x3f) ? count : count + 1; dev->tx_skb = skb; usb_fill_bulk_urb(dev->tx_urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), @@ -694,11 +697,11 @@ static netdev_tx_t rtl8150_start_xmit(struct sk_buff *skb, netdev->stats.tx_errors++; netif_start_queue(netdev); } } else { netdev->stats.tx_packets++; - netdev->stats.tx_bytes += skb->len; + netdev->stats.tx_bytes += skb_len; netif_trans_update(netdev); } return NETDEV_TX_OK; } -- 2.43.0

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[PATCH OLK-5.10] net: usb: rtl8150: fix use-after-free in rtl8150_start_xmit()
by Zhang Qilong 15 Sep '26

15 Sep '26

From: Zhan Jun <zhanjun(a)uniontech.com> stable inclusion from stable-v5.10.258 commit 5af290c86fa81ddbc86a08d54229af5daa40c6a4 category: bugfix bugzilla: https://gitcode.com/src-openeuler/kernel/issues/15684 CVE: CVE-2026-52982 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 23f0e34c64acba15cad4d23e50f41f533da195fa ] syzbot reported a KASAN slab-use-after-free read in rtl8150_start_xmit() when accessing skb->len for tx statistics after usb_submit_urb() has been called: BUG: KASAN: slab-use-after-free in rtl8150_start_xmit+0x71f/0x760 drivers/net/usb/rtl8150.c:712 Read of size 4 at addr ffff88810eb7a930 by task kworker/0:4/5226 The URB completion handler write_bulk_callback() frees the skb via dev_kfree_skb_irq(dev->tx_skb). The URB may complete on another CPU in softirq context before usb_submit_urb() returns in the submitter, so by the time the submitter reads skb->len the skb has already been queued to the per-CPU completion_queue and freed by net_tx_action(): CPU A (xmit) CPU B (USB completion softirq) ------------ ------------------------------ dev->tx_skb = skb; usb_submit_urb() --+ |-------> write_bulk_callback() | dev_kfree_skb_irq(dev->tx_skb) | net_tx_action() | napi_skb_cache_put() <-- free netdev->stats.tx_bytes | += skb->len; <-- UAF read Fix it by caching skb->len before submitting the URB and using the cached value when updating the tx_bytes counter. The pre-existing tx_bytes semantics are preserved: the counter tracks the original frame length (skb->len), not the ETH_ZLEN/USB-alignment padded "count" value that is handed to the device. Changing that would be a user-visible accounting change and is out of scope for this UAF fix. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+3f46c095ac0ca048cb71(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69e69ee7.050a0220.24bfd3.002b.GAE@google.com/ Closes: https://syzkaller.appspot.com/bug?extid=3f46c095ac0ca048cb71 Reviewed-by: Andrew Lunn <andrew(a)lunn.ch> Signed-off-by: Zhan Jun <zhanjun(a)uniontech.com> Link: https://patch.msgid.link/809895186B866C10+20260423004913.136655-1-zhangdand… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: drivers/net/usb/rtl8150.c [Just context confilcts] Signed-off-by: Zhang Qilong <zhangqilong3(a)huawei.com> --- drivers/net/usb/rtl8150.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c index bf8a60533f3e..7b775cd89f4a 100644 --- a/drivers/net/usb/rtl8150.c +++ b/drivers/net/usb/rtl8150.c @@ -675,12 +675,15 @@ static void rtl8150_set_multicast(struct net_device *netdev) static netdev_tx_t rtl8150_start_xmit(struct sk_buff *skb, struct net_device *netdev) { rtl8150_t *dev = netdev_priv(netdev); + unsigned int skb_len; int count, res; + skb_len = skb->len; + netif_stop_queue(netdev); count = (skb->len < 60) ? 60 : skb->len; count = (count & 0x3f) ? count : count + 1; dev->tx_skb = skb; usb_fill_bulk_urb(dev->tx_urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), @@ -694,11 +697,11 @@ static netdev_tx_t rtl8150_start_xmit(struct sk_buff *skb, netdev->stats.tx_errors++; netif_start_queue(netdev); } } else { netdev->stats.tx_packets++; - netdev->stats.tx_bytes += skb->len; + netdev->stats.tx_bytes += skb_len; netif_trans_update(netdev); } return NETDEV_TX_OK; } -- 2.43.0

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