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[PATCH OLK-5.10] x86/crash: Disable virt in core NMI crash handler to avoid double shootdown
by Yu Liao 23 Aug '23

23 Aug '23

From: Sean Christopherson <seanjc(a)google.com> stable inclusion from stable-v5.10.173 commit 8ff2cc2f87750507048d372e8d0f4d27ef446d3b category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7V9HD Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 26044aff37a5455b19a91785086914fd33053ef4 upstream. Disable virtualization in crash_nmi_callback() and rework the emergency_vmx_disable_all() path to do an NMI shootdown if and only if a shootdown has not already occurred. NMI crash shootdown fundamentally can't support multiple invocations as responding CPUs are deliberately put into halt state without unblocking NMIs. But, the emergency reboot path doesn't have any work of its own, it simply cares about disabling virtualization, i.e. so long as a shootdown occurred, emergency reboot doesn't care who initiated the shootdown, or when. If "crash_kexec_post_notifiers" is specified on the kernel command line, panic() will invoke crash_smp_send_stop() and result in a second call to nmi_shootdown_cpus() during native_machine_emergency_restart(). Invoke the callback _before_ disabling virtualization, as the current VMCS needs to be cleared before doing VMXOFF. Note, this results in a subtle change in ordering between disabling virtualization and stopping Intel PT on the responding CPUs. While VMX and Intel PT do interact, VMXOFF and writes to MSR_IA32_RTIT_CTL do not induce faults between one another, which is all that matters when panicking. Harden nmi_shootdown_cpus() against multiple invocations to try and capture any such kernel bugs via a WARN instead of hanging the system during a crash/dump, e.g. prior to the recent hardening of register_nmi_handler(), re-registering the NMI handler would trigger a double list_add() and hang the system if CONFIG_BUG_ON_DATA_CORRUPTION=y. list_add double add: new=ffffffff82220800, prev=ffffffff8221cfe8, next=ffffffff82220800. WARNING: CPU: 2 PID: 1319 at lib/list_debug.c:29 __list_add_valid+0x67/0x70 Call Trace: __register_nmi_handler+0xcf/0x130 nmi_shootdown_cpus+0x39/0x90 native_machine_emergency_restart+0x1c9/0x1d0 panic+0x237/0x29b Extract the disabling logic to a common helper to deduplicate code, and to prepare for doing the shootdown in the emergency reboot path if SVM is supported. Note, prior to commit ed72736183c4 ("x86/reboot: Force all cpus to exit VMX root if VMX is supported"), nmi_shootdown_cpus() was subtly protected against a second invocation by a cpu_vmx_enabled() check as the kdump handler would disable VMX if it ran first. Fixes: ed72736183c4 ("x86/reboot: Force all cpus to exit VMX root if VMX is supported") Cc: stable(a)vger.kernel.org Reported-by: Guilherme G. Piccoli <gpiccoli(a)igalia.com> Cc: Vitaly Kuznetsov <vkuznets(a)redhat.com> Cc: Paolo Bonzini <pbonzini(a)redhat.com> Link: https://lore.kernel.org/all/20220427224924.592546-2-gpiccoli@igalia.com Tested-by: Guilherme G. Piccoli <gpiccoli(a)igalia.com> Reviewed-by: Thomas Gleixner <tglx(a)linutronix.de> Link: https://lore.kernel.org/r/20221130233650.1404148-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc(a)google.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yu Liao <liaoyu15(a)huawei.com> --- arch/x86/include/asm/reboot.h | 2 ++ arch/x86/kernel/crash.c | 17 +-------- arch/x86/kernel/reboot.c | 65 ++++++++++++++++++++++++++++------- 3 files changed, 56 insertions(+), 28 deletions(-) diff --git a/arch/x86/include/asm/reboot.h b/arch/x86/include/asm/reboot.h index 04c17be9b5fd..bc5b4d788c08 100644 --- a/arch/x86/include/asm/reboot.h +++ b/arch/x86/include/asm/reboot.h @@ -25,6 +25,8 @@ void __noreturn machine_real_restart(unsigned int type); #define MRR_BIOS 0 #define MRR_APM 1 +void cpu_emergency_disable_virtualization(void); + typedef void (*nmi_shootdown_cb)(int, struct pt_regs*); void nmi_panic_self_stop(struct pt_regs *regs); void nmi_shootdown_cpus(nmi_shootdown_cb callback); diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 54ce999ed321..bd4b566ec917 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -37,7 +37,6 @@ #include <linux/kdebug.h> #include <asm/cpu.h> #include <asm/reboot.h> -#include <asm/virtext.h> #include <asm/intel_pt.h> #include <asm/crash.h> #include <asm/cmdline.h> @@ -94,15 +93,6 @@ static void kdump_nmi_callback(int cpu, struct pt_regs *regs) */ cpu_crash_vmclear_loaded_vmcss(); - /* Disable VMX or SVM if needed. - * - * We need to disable virtualization on all CPUs. - * Having VMX or SVM enabled on any CPU may break rebooting - * after the kdump kernel has finished its task. - */ - cpu_emergency_vmxoff(); - cpu_emergency_svm_disable(); - /* * Disable Intel PT to stop its logging */ @@ -161,12 +151,7 @@ void native_machine_crash_shutdown(struct pt_regs *regs) */ cpu_crash_vmclear_loaded_vmcss(); - /* Booting kdump kernel with VMX or SVM enabled won't work, - * because (among other limitations) we can't disable paging - * with the virt flags. - */ - cpu_emergency_vmxoff(); - cpu_emergency_svm_disable(); + cpu_emergency_disable_virtualization(); /* * Disable Intel PT to stop its logging diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index df951a8f39d2..d68c8b9a3775 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -528,10 +528,7 @@ static inline void kb_wait(void) } } -static void vmxoff_nmi(int cpu, struct pt_regs *regs) -{ - cpu_emergency_vmxoff(); -} +static inline void nmi_shootdown_cpus_on_restart(void); /* Use NMIs as IPIs to tell all CPUs to disable virtualization */ static void emergency_vmx_disable_all(void) @@ -554,7 +551,7 @@ static void emergency_vmx_disable_all(void) __cpu_emergency_vmxoff(); /* Halt and exit VMX root operation on the other CPUs. */ - nmi_shootdown_cpus(vmxoff_nmi); + nmi_shootdown_cpus_on_restart(); } } @@ -795,6 +792,17 @@ void machine_crash_shutdown(struct pt_regs *regs) /* This is the CPU performing the emergency shutdown work. */ int crashing_cpu = -1; +/* + * Disable virtualization, i.e. VMX or SVM, to ensure INIT is recognized during + * reboot. VMX blocks INIT if the CPU is post-VMXON, and SVM blocks INIT if + * GIF=0, i.e. if the crash occurred between CLGI and STGI. + */ +void cpu_emergency_disable_virtualization(void) +{ + cpu_emergency_vmxoff(); + cpu_emergency_svm_disable(); +} + #if defined(CONFIG_SMP) static nmi_shootdown_cb shootdown_callback; @@ -817,7 +825,14 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) return NMI_HANDLED; local_irq_disable(); - shootdown_callback(cpu, regs); + if (shootdown_callback) + shootdown_callback(cpu, regs); + + /* + * Prepare the CPU for reboot _after_ invoking the callback so that the + * callback can safely use virtualization instructions, e.g. VMCLEAR. + */ + cpu_emergency_disable_virtualization(); atomic_dec(&waiting_for_crash_ipi); /* Assume hlt works */ @@ -828,18 +843,32 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) return NMI_HANDLED; } -/* - * Halt all other CPUs, calling the specified function on each of them +/** + * nmi_shootdown_cpus - Stop other CPUs via NMI + * @callback: Optional callback to be invoked from the NMI handler + * + * The NMI handler on the remote CPUs invokes @callback, if not + * NULL, first and then disables virtualization to ensure that + * INIT is recognized during reboot. * - * This function can be used to halt all other CPUs on crash - * or emergency reboot time. The function passed as parameter - * will be called inside a NMI handler on all CPUs. + * nmi_shootdown_cpus() can only be invoked once. After the first + * invocation all other CPUs are stuck in crash_nmi_callback() and + * cannot respond to a second NMI. */ void nmi_shootdown_cpus(nmi_shootdown_cb callback) { unsigned long msecs; + local_irq_disable(); + /* + * Avoid certain doom if a shootdown already occurred; re-registering + * the NMI handler will cause list corruption, modifying the callback + * will do who knows what, etc... + */ + if (WARN_ON_ONCE(crash_ipi_issued)) + return; + /* Make a note of crashing cpu. Will be used in NMI callback. */ crashing_cpu = safe_smp_processor_id(); @@ -875,7 +904,17 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback) msecs--; } - /* Leave the nmi callback set */ + /* + * Leave the nmi callback set, shootdown is a one-time thing. Clearing + * the callback could result in a NULL pointer dereference if a CPU + * (finally) responds after the timeout expires. + */ +} + +static inline void nmi_shootdown_cpus_on_restart(void) +{ + if (!crash_ipi_issued) + nmi_shootdown_cpus(NULL); } /* @@ -905,6 +944,8 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback) /* No other CPUs to shoot down */ } +static inline void nmi_shootdown_cpus_on_restart(void) { } + void run_crash_ipi_callback(struct pt_regs *regs) { } -- 2.25.1

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[PATCH openEuler-1.0-LTS] net: vmxnet3: fix possible NULL pointer dereference in vmxnet3_rq_cleanup()
by Zhengchao Shao 22 Aug '23

22 Aug '23

From: Zixuan Fu <r33s3n6(a)gmail.com> mainline inclusion from mainline-v5.18-rc1 commit edf410cb74dc612fd47ef5be319c5a0bcd6e6ccd category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7UWI8 CVE: CVE-2023-4459 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- In vmxnet3_rq_create(), when dma_alloc_coherent() fails, vmxnet3_rq_destroy() is called. It sets rq->rx_ring[i].base to NULL. Then vmxnet3_rq_create() returns an error to its callers mxnet3_rq_create_all() -> vmxnet3_change_mtu(). Then vmxnet3_change_mtu() calls vmxnet3_force_close() -> dev_close() in error handling code. And the driver calls vmxnet3_close() -> vmxnet3_quiesce_dev() -> vmxnet3_rq_cleanup_all() -> vmxnet3_rq_cleanup(). In vmxnet3_rq_cleanup(), rq->rx_ring[ring_idx].base is accessed, but this variable is NULL, causing a NULL pointer dereference. To fix this possible bug, an if statement is added to check whether rq->rx_ring[0].base is NULL in vmxnet3_rq_cleanup() and exit early if so. The error log in our fault-injection testing is shown as follows: [ 65.220135] BUG: kernel NULL pointer dereference, address: 0000000000000008 ... [ 65.222633] RIP: 0010:vmxnet3_rq_cleanup_all+0x396/0x4e0 [vmxnet3] ... [ 65.227977] Call Trace: ... [ 65.228262] vmxnet3_quiesce_dev+0x80f/0x8a0 [vmxnet3] [ 65.228580] vmxnet3_close+0x2c4/0x3f0 [vmxnet3] [ 65.228866] __dev_close_many+0x288/0x350 [ 65.229607] dev_close_many+0xa4/0x480 [ 65.231124] dev_close+0x138/0x230 [ 65.231933] vmxnet3_force_close+0x1f0/0x240 [vmxnet3] [ 65.232248] vmxnet3_change_mtu+0x75d/0x920 [vmxnet3] ... Fixes: d1a890fa37f27 ("net: VMware virtual Ethernet NIC driver: vmxnet3") Reported-by: TOTE Robot <oslab(a)tsinghua.edu.cn> Signed-off-by: Zixuan Fu <r33s3n6(a)gmail.com> Link: https://lore.kernel.org/r/20220514050711.2636709-1-r33s3n6@gmail.com Signed-off-by: Paolo Abeni <pabeni(a)redhat.com> Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com> --- drivers/net/vmxnet3/vmxnet3_drv.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c index e454dfc9ad8f..f5cf7643289b 100644 --- a/drivers/net/vmxnet3/vmxnet3_drv.c +++ b/drivers/net/vmxnet3/vmxnet3_drv.c @@ -1584,6 +1584,10 @@ vmxnet3_rq_cleanup(struct vmxnet3_rx_queue *rq, u32 i, ring_idx; struct Vmxnet3_RxDesc *rxd; + /* ring has already been cleaned up */ + if (!rq->rx_ring[0].base) + return; + for (ring_idx = 0; ring_idx < 2; ring_idx++) { for (i = 0; i < rq->rx_ring[ring_idx].size; i++) { #ifdef __BIG_ENDIAN_BITFIELD -- 2.34.1

2 1

[PATCH OLK-5.10] net: bridge: multicast: notify switchdev driver whenever MC processing gets disabled
by Zhengchao Shao 22 Aug '23

22 Aug '23

From: Oleksandr Mazur <oleksandr.mazur(a)plvision.eu> mainline inclusion from mainline-v5.17-rc5 commit c832962ac972082b3a1f89775c9d4274c8cb5670 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7V613 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- Whenever bridge driver hits the max capacity of MDBs, it disables the MC processing (by setting corresponding bridge option), but never notifies switchdev about such change (the notifiers are called only upon explicit setting of this option, through the registered netlink interface). This could lead to situation when Software MDB processing gets disabled, but this event never gets offloaded to the underlying Hardware. Fix this by adding a notify message in such case. Fixes: 147c1e9b902c ("switchdev: bridge: Offload multicast disabled") Signed-off-by: Oleksandr Mazur <oleksandr.mazur(a)plvision.eu> Acked-by: Nikolay Aleksandrov <nikolay(a)nvidia.com> Link: https://lore.kernel.org/r/20220215165303.31908-1-oleksandr.mazur@plvision.eu Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Conflicts: net/bridge/br_multicast.c Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com> --- net/bridge/br_multicast.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index de79fbfe1611..e2b1bb3de4a1 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -48,6 +48,8 @@ static const struct rhashtable_params br_sg_port_rht_params = { .automatic_shrinking = true, }; +static void br_mc_disabled_update(struct net_device *dev, bool value); + static void br_multicast_start_querier(struct net_bridge *br, struct bridge_mcast_own_query *query); static void br_multicast_add_router(struct net_bridge *br, @@ -1040,6 +1042,7 @@ struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br, return mp; if (atomic_read(&br->mdb_hash_tbl.nelems) >= br->hash_max) { + br_mc_disabled_update(br->dev, false); br_opt_toggle(br, BROPT_MULTICAST_ENABLED, false); return ERR_PTR(-E2BIG); } -- 2.34.1

2 1

[PATCH openEuler-23.09 00/12] Add SDEI Watchdog Support
by Xiongfeng Wang 22 Aug '23

22 Aug '23

Xiongfeng Wang (12): watchdog: make hardlockup detect code public firmware: arm_sdei: add interrupt binding api firmware: arm_sdei: make 'sdei_api_event_disable/enable' public lockup_detector: init lockup detector after all the init_calls watchdog: add nmi_watchdog support for arm64 based on SDEI sdei_watchdog: refresh 'last_timestamp' when enabling nmi_watchdog sdei_watchdog: clear EOI of the secure timer before kdump sdei_watchdog: set secure timer period base on 'watchdog_thresh' kprobes/arm64: Blacklist sdei watchdog callback functions sdei_watchdog: avoid possible false hardlockup init: only move down lockup_detector_init() when sdei_watchdog is enabled openeuler_defconfig: Enable SDEI Watchdog arch/arm64/configs/openeuler_defconfig | 2 + arch/arm64/kernel/Makefile | 1 + arch/arm64/kernel/machine_kexec.c | 10 ++ arch/arm64/kernel/watchdog_sdei.c | 156 +++++++++++++++++++++++++ drivers/firmware/arm_sdei.c | 26 ++++- include/linux/arm_sdei.h | 5 + include/linux/nmi.h | 24 +++- include/uapi/linux/arm_sdei.h | 2 + init/main.c | 7 +- kernel/Makefile | 2 +- kernel/watchdog.c | 2 + kernel/watchdog_hld.c | 61 ++++++---- lib/Kconfig.debug | 8 +- 13 files changed, 278 insertions(+), 28 deletions(-) create mode 100644 arch/arm64/kernel/watchdog_sdei.c -- 2.20.1

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[PATCH openEuler-22.03-LTS-SP1 0/5] fix CVE-2023-20593 for openEuler
by Yu Liao 22 Aug '23

22 Aug '23

AMD Zen2 architecture Zenbleed remote execution vulnerability. The optimal fix is through microcode but in the case the proper microcode revision has not been applied, enable a fallback fix for openEuler. Arnaldo Carvalho de Melo (1): tools arch x86: Sync the msr-index.h copy with the kernel sources Borislav Petkov (1): x86/cpu: Restore AMD's DE_CFG MSR after resume Borislav Petkov (AMD) (2): x86/cpu/amd: Move the errata checking functionality up x86/cpu/amd: Add a Zenbleed fix Cristian Ciocaltea (1): x86/cpu/amd: Enable Zenbleed fix for AMD Custom APU 0405 arch/x86/include/asm/microcode.h | 1 + arch/x86/include/asm/microcode_amd.h | 2 + arch/x86/include/asm/msr-index.h | 9 +- arch/x86/kernel/cpu/amd.c | 206 ++++++++++++++++--------- arch/x86/kernel/cpu/common.c | 1 + arch/x86/kernel/cpu/hygon.c | 4 +- arch/x86/kvm/svm/svm.c | 10 +- arch/x86/kvm/x86.c | 2 +- arch/x86/power/cpu.c | 1 + tools/arch/x86/include/asm/msr-index.h | 9 +- 10 files changed, 155 insertions(+), 90 deletions(-) -- 2.25.1

2 6

[PATCH openEuler-22.03-LTS 0/5] fix CVE-2023-20593 for openEuler
by Yu Liao 22 Aug '23

22 Aug '23

AMD Zen2 architecture Zenbleed remote execution vulnerability. The optimal fix is through microcode but in the case the proper microcode revision has not been applied, enable a fallback fix for openEuler. Arnaldo Carvalho de Melo (1): tools arch x86: Sync the msr-index.h copy with the kernel sources Borislav Petkov (1): x86/cpu: Restore AMD's DE_CFG MSR after resume Borislav Petkov (AMD) (2): x86/cpu/amd: Move the errata checking functionality up x86/cpu/amd: Add a Zenbleed fix Cristian Ciocaltea (1): x86/cpu/amd: Enable Zenbleed fix for AMD Custom APU 0405 arch/x86/include/asm/microcode.h | 1 + arch/x86/include/asm/microcode_amd.h | 2 + arch/x86/include/asm/msr-index.h | 9 +- arch/x86/kernel/cpu/amd.c | 206 ++++++++++++++++--------- arch/x86/kernel/cpu/common.c | 1 + arch/x86/kernel/cpu/hygon.c | 4 +- arch/x86/kvm/svm/svm.c | 10 +- arch/x86/kvm/x86.c | 2 +- arch/x86/power/cpu.c | 1 + tools/arch/x86/include/asm/msr-index.h | 9 +- 10 files changed, 155 insertions(+), 90 deletions(-) -- 2.25.1

2 6

[PATCH openEuler-1.0-LTS] tcp: Reduce chance of collisions in inet6_hashfn().
by Wang Yufen 22 Aug '23

22 Aug '23

From: Stewart Smith <trawets(a)amazon.com> stable inclusion from stable-v4.19.291 commit d11b0df7ddf1831f3e170972f43186dad520bfcc category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7FUFX CVE: CVE-2023-1206 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit d11b0df7ddf1831f3e170972f43186dad520bfcc ] For both IPv4 and IPv6 incoming TCP connections are tracked in a hash table with a hash over the source & destination addresses and ports. However, the IPv6 hash is insufficient and can lead to a high rate of collisions. The IPv6 hash used an XOR to fit everything into the 96 bits for the fast jenkins hash, meaning it is possible for an external entity to ensure the hash collides, thus falling back to a linear search in the bucket, which is slow. We take the approach of hash the full length of IPv6 address in __ipv6_addr_jhash() so that all users can benefit from a more secure version. While this may look like it adds overhead, the reality of modern CPUs means that this is unmeasurable in real world scenarios. In simulating with llvm-mca, the increase in cycles for the hashing code was ~16 cycles on Skylake (from a base of ~155), and an extra ~9 on Nehalem (base of ~173). In commit dd6d2910c5e0 ("netfilter: conntrack: switch to siphash") netfilter switched from a jenkins hash to a siphash, but even the faster hsiphash is a more significant overhead (~20-30%) in some preliminary testing. So, in this patch, we keep to the more conservative approach to ensure we don't add much overhead per SYN. In testing, this results in a consistently even spread across the connection buckets. In both testing and real-world scenarios, we have not found any measurable performance impact. Fixes: 08dcdbf6a7b9 ("ipv6: use a stronger hash for tcp") Signed-off-by: Stewart Smith <trawets(a)amazon.com> Signed-off-by: Samuel Mendoza-Jonas <samjonas(a)amazon.com> Suggested-by: Eric Dumazet <edumazet(a)google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu(a)amazon.com> Reviewed-by: Eric Dumazet <edumazet(a)google.com> Link: https://lore.kernel.org/r/20230721222410.17914-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Wang Yufen <wangyufen(a)huawei.com> --- include/net/ipv6.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 0c88324..3a55a093 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -602,12 +602,8 @@ static inline u32 ipv6_addr_hash(const struct in6_addr *a) /* more secured version of ipv6_addr_hash() */ static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) { - u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; - - return jhash_3words(v, - (__force u32)a->s6_addr32[2], - (__force u32)a->s6_addr32[3], - initval); + return jhash2((__force const u32 *)a->s6_addr32, + ARRAY_SIZE(a->s6_addr32), initval); } static inline bool ipv6_addr_loopback(const struct in6_addr *a) -- 1.8.3.1

2 1

[PATCH OLK-5.10] tcp: Reduce chance of collisions in inet6_hashfn().
by Wang Yufen 22 Aug '23

22 Aug '23

From: Stewart Smith <trawets(a)amazon.com> stable inclusion from stable-v5.10.190 commit d11b0df7ddf1831f3e170972f43186dad520bfcc category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7FUFX CVE: CVE-2023-1206 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit d11b0df7ddf1831f3e170972f43186dad520bfcc ] For both IPv4 and IPv6 incoming TCP connections are tracked in a hash table with a hash over the source & destination addresses and ports. However, the IPv6 hash is insufficient and can lead to a high rate of collisions. The IPv6 hash used an XOR to fit everything into the 96 bits for the fast jenkins hash, meaning it is possible for an external entity to ensure the hash collides, thus falling back to a linear search in the bucket, which is slow. We take the approach of hash the full length of IPv6 address in __ipv6_addr_jhash() so that all users can benefit from a more secure version. While this may look like it adds overhead, the reality of modern CPUs means that this is unmeasurable in real world scenarios. In simulating with llvm-mca, the increase in cycles for the hashing code was ~16 cycles on Skylake (from a base of ~155), and an extra ~9 on Nehalem (base of ~173). In commit dd6d2910c5e0 ("netfilter: conntrack: switch to siphash") netfilter switched from a jenkins hash to a siphash, but even the faster hsiphash is a more significant overhead (~20-30%) in some preliminary testing. So, in this patch, we keep to the more conservative approach to ensure we don't add much overhead per SYN. In testing, this results in a consistently even spread across the connection buckets. In both testing and real-world scenarios, we have not found any measurable performance impact. Fixes: 08dcdbf6a7b9 ("ipv6: use a stronger hash for tcp") Signed-off-by: Stewart Smith <trawets(a)amazon.com> Signed-off-by: Samuel Mendoza-Jonas <samjonas(a)amazon.com> Suggested-by: Eric Dumazet <edumazet(a)google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu(a)amazon.com> Reviewed-by: Eric Dumazet <edumazet(a)google.com> Link: https://lore.kernel.org/r/20230721222410.17914-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Wang Yufen <wangyufen(a)huawei.com> --- include/net/ipv6.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 9a5b617..f2585cc 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -663,12 +663,8 @@ static inline u32 ipv6_addr_hash(const struct in6_addr *a) /* more secured version of ipv6_addr_hash() */ static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) { - u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; - - return jhash_3words(v, - (__force u32)a->s6_addr32[2], - (__force u32)a->s6_addr32[3], - initval); + return jhash2((__force const u32 *)a->s6_addr32, + ARRAY_SIZE(a->s6_addr32), initval); } static inline bool ipv6_addr_loopback(const struct in6_addr *a) -- 1.8.3.1

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[OLK-5.10] tcp: Reduce chance of collisions in inet6_hashfn().
by Wang Yufen 22 Aug '23

22 Aug '23

From: Stewart Smith <trawets(a)amazon.com> stable inclusion from stable-v5.10.190 commit d11b0df7ddf1831f3e170972f43186dad520bfcc category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7FUFX CVE: CVE-2023-1206 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit d11b0df7ddf1831f3e170972f43186dad520bfcc ] For both IPv4 and IPv6 incoming TCP connections are tracked in a hash table with a hash over the source & destination addresses and ports. However, the IPv6 hash is insufficient and can lead to a high rate of collisions. The IPv6 hash used an XOR to fit everything into the 96 bits for the fast jenkins hash, meaning it is possible for an external entity to ensure the hash collides, thus falling back to a linear search in the bucket, which is slow. We take the approach of hash the full length of IPv6 address in __ipv6_addr_jhash() so that all users can benefit from a more secure version. While this may look like it adds overhead, the reality of modern CPUs means that this is unmeasurable in real world scenarios. In simulating with llvm-mca, the increase in cycles for the hashing code was ~16 cycles on Skylake (from a base of ~155), and an extra ~9 on Nehalem (base of ~173). In commit dd6d2910c5e0 ("netfilter: conntrack: switch to siphash") netfilter switched from a jenkins hash to a siphash, but even the faster hsiphash is a more significant overhead (~20-30%) in some preliminary testing. So, in this patch, we keep to the more conservative approach to ensure we don't add much overhead per SYN. In testing, this results in a consistently even spread across the connection buckets. In both testing and real-world scenarios, we have not found any measurable performance impact. Fixes: 08dcdbf6a7b9 ("ipv6: use a stronger hash for tcp") Signed-off-by: Stewart Smith <trawets(a)amazon.com> Signed-off-by: Samuel Mendoza-Jonas <samjonas(a)amazon.com> Suggested-by: Eric Dumazet <edumazet(a)google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu(a)amazon.com> Reviewed-by: Eric Dumazet <edumazet(a)google.com> Link: https://lore.kernel.org/r/20230721222410.17914-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Wang Yufen <wangyufen(a)huawei.com> --- include/net/ipv6.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 9a5b617..f2585cc 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -663,12 +663,8 @@ static inline u32 ipv6_addr_hash(const struct in6_addr *a) /* more secured version of ipv6_addr_hash() */ static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) { - u32 v = (__force u32)a->s6_addr32[0] ^ (__force u32)a->s6_addr32[1]; - - return jhash_3words(v, - (__force u32)a->s6_addr32[2], - (__force u32)a->s6_addr32[3], - initval); + return jhash2((__force const u32 *)a->s6_addr32, + ARRAY_SIZE(a->s6_addr32), initval); } static inline bool ipv6_addr_loopback(const struct in6_addr *a) -- 1.8.3.1

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[PATCH OLK-5.10] xsk: Initialise xskb free_list_node
by Zhengchao Shao 22 Aug '23

22 Aug '23

From: Ciara Loftus <ciara.loftus(a)intel.com> mainline inclusion from mainline-v5.16-rc8 commit 5bec7ca2be6955ca1aa0d7bae2b981de9b1c9844 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7UZT5 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- This commit initialises the xskb's free_list_node when the xskb is allocated. This prevents a potential false negative returned from a call to list_empty for that node, such as the one introduced in commit 199d983bc015 ("xsk: Fix crash on double free in buffer pool") In my environment this issue caused packets to not be received by the xdpsock application if the traffic was running prior to application launch. This happened when the first batch of packets failed the xskmap lookup and XDP_PASS was returned from the bpf program. This action is handled in the i40e zc driver (and others) by allocating an skbuff, freeing the xdp_buff and adding the associated xskb to the xsk_buff_pool's free_list if it hadn't been added already. Without this fix, the xskb is not added to the free_list because the check to determine if it was added already returns an invalid positive result. Later, this caused allocation errors in the driver and the failure to receive packets. Fixes: 199d983bc015 ("xsk: Fix crash on double free in buffer pool") Fixes: 2b43470add8c ("xsk: Introduce AF_XDP buffer allocation API") Signed-off-by: Ciara Loftus <ciara.loftus(a)intel.com> Acked-by: Magnus Karlsson <magnus.karlsson(a)intel.com> Link: https://lore.kernel.org/r/20211220155250.2746-1-ciara.loftus@intel.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Conflicts: net/xdp/xsk_buff_pool.c Signed-off-by: Zhengchao Shao <shaozhengchao(a)huawei.com> --- net/xdp/xsk_buff_pool.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c index c347e52f58df..383c083faa01 100644 --- a/net/xdp/xsk_buff_pool.c +++ b/net/xdp/xsk_buff_pool.c @@ -81,6 +81,7 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, xskb = &pool->heads[i]; xskb->pool = pool; xskb->xdp.frame_sz = umem->chunk_size - umem->headroom; + INIT_LIST_HEAD(&xskb->free_list_node); pool->free_heads[i] = xskb; } -- 2.34.1

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