February 2024 - Linux-stable-mirror

[PATCH] usb: gadget: u_serial: Add null pointer checks after RX/TX submission

by Kuen-Han Tsai

Commit ffd603f21423 ("usb: gadget: u_serial: Add null pointer check in gs_start_io") adds null pointer checks to gs_start_io(), but it doesn't fully fix the potential null pointer dereference issue. While gserial_connect() calls gs_start_io() with port_lock held, gs_start_rx() and gs_start_tx() release the lock during endpoint request submission. This creates a window where gs_close() could set port->port_tty to NULL, leading to a dereference when the lock is reacquired. This patch adds a null pointer check for port->port_tty after RX/TX submission, and removes the initial null pointer check in gs_start_io() since the caller must hold port_lock and guarantee non-null values for port_usb and port_tty. Fixes: ffd603f21423 ("usb: gadget: u_serial: Add null pointer check in gs_start_io") Cc: stable(a)vger.kernel.org Signed-off-by: Kuen-Han Tsai <khtsai(a)google.com> --- Explanation: CPU1: CPU2: gserial_connect() // lock gs_close() // await lock gs_start_rx() // unlock usb_ep_queue() gs_close() // lock, reset port_tty and unlock gs_start_rx() // lock tty_wakeup() // dereference Stack traces: [ 51.494375][ T278] ttyGS1: shutdown [ 51.494817][ T269] android_work: sent uevent USB_STATE=DISCONNECTED [ 52.115792][ T1508] usb: [dm_bind] generic ttyGS1: super speed IN/ep1in OUT/ep1out [ 52.516288][ T1026] android_work: sent uevent USB_STATE=CONNECTED [ 52.551667][ T1533] gserial_connect: start ttyGS1 [ 52.565634][ T1533] [khtsai] enter gs_start_io, ttyGS1, port->port.tty=0000000046bd4060 [ 52.565671][ T1533] [khtsai] gs_start_rx, unlock port ttyGS1 [ 52.591552][ T1533] [khtsai] gs_start_rx, lock port ttyGS1 [ 52.619901][ T1533] [khtsai] gs_start_rx, unlock port ttyGS1 [ 52.638659][ T1325] [khtsai] gs_close, lock port ttyGS1 [ 52.656842][ T1325] gs_close: ttyGS1 (0000000046bd4060,00000000be9750a5) ... [ 52.683005][ T1325] [khtsai] gs_close, clear ttyGS1 [ 52.683007][ T1325] gs_close: ttyGS1 (0000000046bd4060,00000000be9750a5) done! [ 52.708643][ T1325] [khtsai] gs_close, unlock port ttyGS1 [ 52.747592][ T1533] [khtsai] gs_start_rx, lock port ttyGS1 [ 52.747616][ T1533] [khtsai] gs_start_io, ttyGS1, going to call tty_wakeup(), port->port.tty=0000000000000000 [ 52.747629][ T1533] Unable to handle kernel NULL pointer dereference at virtual address 00000000000001f8 --- drivers/usb/gadget/function/u_serial.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index a92eb6d90976..2f1890c8f473 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -539,20 +539,16 @@ static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head, static int gs_start_io(struct gs_port *port) { struct list_head *head = &port->read_pool; - struct usb_ep *ep; + struct usb_ep *ep = port->port_usb->out; int status; unsigned started; - if (!port->port_usb || !port->port.tty) - return -EIO; - /* Allocate RX and TX I/O buffers. We can't easily do this much * earlier (with GFP_KERNEL) because the requests are coupled to * endpoints, as are the packet sizes we'll be using. Different * configurations may use different endpoints with a given port; * and high speed vs full speed changes packet sizes too. */ - ep = port->port_usb->out; status = gs_alloc_requests(ep, head, gs_read_complete, &port->read_allocated); if (status) @@ -569,12 +565,22 @@ static int gs_start_io(struct gs_port *port) port->n_read = 0; started = gs_start_rx(port); + /* + * The TTY may be set to NULL by gs_close() after gs_start_rx() or + * gs_start_tx() release locks for endpoint request submission. + */ + if (!port->port.tty) + goto out; + if (started) { gs_start_tx(port); /* Unblock any pending writes into our circular buffer, in case * we didn't in gs_start_tx() */ + if (!port->port.tty) + goto out; tty_wakeup(port->port.tty); } else { +out: gs_free_requests(ep, head, &port->read_allocated); gs_free_requests(port->port_usb->in, &port->write_pool, &port->write_allocated); -- 2.43.0.275.g3460e3d667-goog

5 months, 1 week

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FAILED: patch "[PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072323-trident-unturned-7999@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: b321c31c9b7b ("KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption") 0c2f9acf6ae7 ("KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded") 8681f7175901 ("KVM: arm64: PMU: Restore the host's PMUSERENR_EL0") 009d6dc87a56 ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM") 711432770f78 ("perf: pmuv3: Abstract PMU version checks") df29ddf4f04b ("arm64: perf: Abstract system register accesses away") 7755cec63ade ("arm64: perf: Move PMUv3 driver to drivers/perf") cc91b9481605 ("arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI") 4151bb636acf ("KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHE") bb0cca240a16 ("Merge branch kvm-arm64/single-step-async-exception into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <maz(a)kernel.org> Date: Thu, 13 Jul 2023 08:06:57 +0100 Subject: [PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption Xiang reports that VMs occasionally fail to boot on GICv4.1 systems when running a preemptible kernel, as it is possible that a vCPU is blocked without requesting a doorbell interrupt. The issue is that any preemption that occurs between vgic_v4_put() and schedule() on the block path will mark the vPE as nonresident and *not* request a doorbell irq. This occurs because when the vcpu thread is resumed on its way to block, vcpu_load() will make the vPE resident again. Once the vcpu actually blocks, we don't request a doorbell anymore, and the vcpu won't be woken up on interrupt delivery. Fix it by tracking that we're entering WFI, and key the doorbell request on that flag. This allows us not to make the vPE resident when going through a preempt/schedule cycle, meaning we don't lose any state. Cc: stable(a)vger.kernel.org Fixes: 8e01d9a396e6 ("KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put") Reported-by: Xiang Chen <chenxiang66(a)hisilicon.com> Suggested-by: Zenghui Yu <yuzenghui(a)huawei.com> Tested-by: Xiang Chen <chenxiang66(a)hisilicon.com> Co-developed-by: Oliver Upton <oliver.upton(a)linux.dev> Signed-off-by: Marc Zyngier <maz(a)kernel.org> Acked-by: Zenghui Yu <yuzenghui(a)huawei.com> Link: https://lore.kernel.org/r/20230713070657.3873244-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8b6096753740..d3dd05bbfe23 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -727,6 +727,8 @@ struct kvm_vcpu_arch { #define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5)) /* PMUSERENR for the guest EL0 is on physical CPU */ #define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6)) +/* WFI instruction trapped */ +#define IN_WFI __vcpu_single_flag(sflags, BIT(7)) /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a402ea5511f3..72dc53a75d1c 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -718,13 +718,15 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) */ preempt_disable(); kvm_vgic_vmcr_sync(vcpu); - vgic_v4_put(vcpu, true); + vcpu_set_flag(vcpu, IN_WFI); + vgic_v4_put(vcpu); preempt_enable(); kvm_vcpu_halt(vcpu); vcpu_clear_flag(vcpu, IN_WFIT); preempt_disable(); + vcpu_clear_flag(vcpu, IN_WFI); vgic_v4_load(vcpu); preempt_enable(); } @@ -792,7 +794,7 @@ static int check_vcpu_requests(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { /* The distributor enable bits were changed */ preempt_disable(); - vgic_v4_put(vcpu, false); + vgic_v4_put(vcpu); vgic_v4_load(vcpu); preempt_enable(); } diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index c3b8e132d599..3dfc8b84e03e 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -749,7 +749,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu) { struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3; - WARN_ON(vgic_v4_put(vcpu, false)); + WARN_ON(vgic_v4_put(vcpu)); vgic_v3_vmcr_sync(vcpu); diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c index c1c28fe680ba..339a55194b2c 100644 --- a/arch/arm64/kvm/vgic/vgic-v4.c +++ b/arch/arm64/kvm/vgic/vgic-v4.c @@ -336,14 +336,14 @@ void vgic_v4_teardown(struct kvm *kvm) its_vm->vpes = NULL; } -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db) +int vgic_v4_put(struct kvm_vcpu *vcpu) { struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe; if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident) return 0; - return its_make_vpe_non_resident(vpe, need_db); + return its_make_vpe_non_resident(vpe, !!vcpu_get_flag(vcpu, IN_WFI)); } int vgic_v4_load(struct kvm_vcpu *vcpu) @@ -354,6 +354,9 @@ int vgic_v4_load(struct kvm_vcpu *vcpu) if (!vgic_supports_direct_msis(vcpu->kvm) || vpe->resident) return 0; + if (vcpu_get_flag(vcpu, IN_WFI)) + return 0; + /* * Before making the VPE resident, make sure the redistributor * corresponding to our current CPU expects us here. See the diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 402b545959af..5b27f94d4fad 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -431,7 +431,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq, int vgic_v4_load(struct kvm_vcpu *vcpu); void vgic_v4_commit(struct kvm_vcpu *vcpu); -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db); +int vgic_v4_put(struct kvm_vcpu *vcpu); /* CPU HP callbacks */ void kvm_vgic_cpu_up(void);

5 months, 3 weeks

4
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[PATCH 6.1.y v2 0/6] BPF selftests fixes for 6.1 branch

by Eduard Zingerman

Recently Luiz Capitulino reported BPF test failure for kernel version 6.1.36 (see [7]). The following test_verifier test failed: "precise: ST insn causing spi > allocated_stack". After back-port of the following upstream commit: ecdf985d7615 ("bpf: track immediate values written to stack by BPF_ST instruction") Investigation in [8] shows that test failure is not a bug, but a difference in BPF verifier behavior between upstream, where commits [1,2,3] by Andrii Nakryiko are present, and 6.1.36, where these commits are absent. Both Luiz and Greg suggested back-porting [1,2,3] from upstream to avoid divergences. Commits [1,2,3] break test_progs selftest "align/packet variable offset", commit [4] fixes this selftest. I did some additional testing using the following compiler versions: - Kernel compilation - gcc version 11.3.0 - BPF tests compilation - clang version 16.0.6 - clang version 17.0.0 (fa46feb31481) And identified a few more failing BPF selftests: - Tests failing with LLVM 16: - test_verifier: - precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3]) - test_progs: - sk_assign (fixed by [6]) - Tests failing with LLVM 17: - test_verifier: - precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3]) - test_progs: - fexit_bpf2bpf/func_replace_verify (fixed by [5]) - fexit_bpf2bpf/func_replace_return_code (fixed by [5]) - sk_assign (fixed by [6]) Commits [4,5,6] only apply to BPF selftests and don't change verifier behavior. After applying all of the listed commits I have test_verifier, test_progs, test_progs-no_alu32 and test_maps passing on my x86 setup, both for LLVM 16 and LLVM 17. Upstream commits in chronological order: [1] be2ef8161572 ("bpf: allow precision tracking for programs with subprogs") [2] f63181b6ae79 ("bpf: stop setting precise in current state") [3] 7a830b53c17b ("bpf: aggressively forget precise markings during state checkpointing") [4] 4f999b767769 ("selftests/bpf: make test_align selftest more robust") [5] 63d78b7e8ca2 ("selftests/bpf: Workaround verification failure for fexit_bpf2bpf/func_replace_return_code") [6] 7ce878ca81bc ("selftests/bpf: Fix sk_assign on s390x") Links: [7] https://lore.kernel.org/stable/935c4751-d368-df29-33a6-9f4fcae720fa@amazon.… [8] https://lore.kernel.org/stable/c9b10a8a551edafdfec855fbd35757c6238ad258.cam… Changelog: V1 -> V2: added missing signed-off-by tags V1: https://lore.kernel.org/stable/20230722004514.767618-1-eddyz87@gmail.com/ Reported-by: Luiz Capitulino <luizcap(a)amazon.com> Andrii Nakryiko (4): bpf: allow precision tracking for programs with subprogs bpf: stop setting precise in current state bpf: aggressively forget precise markings during state checkpointing selftests/bpf: make test_align selftest more robust Ilya Leoshkevich (1): selftests/bpf: Fix sk_assign on s390x Yonghong Song (1): selftests/bpf: Workaround verification failure for fexit_bpf2bpf/func_replace_return_code kernel/bpf/verifier.c | 202 ++++++++++++++++-- .../testing/selftests/bpf/prog_tests/align.c | 38 ++-- .../selftests/bpf/prog_tests/sk_assign.c | 25 ++- .../selftests/bpf/progs/connect4_prog.c | 2 +- .../selftests/bpf/progs/test_sk_assign.c | 11 + .../bpf/progs/test_sk_assign_libbpf.c | 3 + 6 files changed, 247 insertions(+), 34 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_sk_assign_libbpf.c -- 2.41.0

5 months, 3 weeks

4
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FAILED: patch "[PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072324-aviation-delirious-b27d@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: b321c31c9b7b ("KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption") 0c2f9acf6ae7 ("KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded") 8681f7175901 ("KVM: arm64: PMU: Restore the host's PMUSERENR_EL0") 009d6dc87a56 ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM") 711432770f78 ("perf: pmuv3: Abstract PMU version checks") df29ddf4f04b ("arm64: perf: Abstract system register accesses away") 7755cec63ade ("arm64: perf: Move PMUv3 driver to drivers/perf") cc91b9481605 ("arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI") 4151bb636acf ("KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHE") bb0cca240a16 ("Merge branch kvm-arm64/single-step-async-exception into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <maz(a)kernel.org> Date: Thu, 13 Jul 2023 08:06:57 +0100 Subject: [PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption Xiang reports that VMs occasionally fail to boot on GICv4.1 systems when running a preemptible kernel, as it is possible that a vCPU is blocked without requesting a doorbell interrupt. The issue is that any preemption that occurs between vgic_v4_put() and schedule() on the block path will mark the vPE as nonresident and *not* request a doorbell irq. This occurs because when the vcpu thread is resumed on its way to block, vcpu_load() will make the vPE resident again. Once the vcpu actually blocks, we don't request a doorbell anymore, and the vcpu won't be woken up on interrupt delivery. Fix it by tracking that we're entering WFI, and key the doorbell request on that flag. This allows us not to make the vPE resident when going through a preempt/schedule cycle, meaning we don't lose any state. Cc: stable(a)vger.kernel.org Fixes: 8e01d9a396e6 ("KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put") Reported-by: Xiang Chen <chenxiang66(a)hisilicon.com> Suggested-by: Zenghui Yu <yuzenghui(a)huawei.com> Tested-by: Xiang Chen <chenxiang66(a)hisilicon.com> Co-developed-by: Oliver Upton <oliver.upton(a)linux.dev> Signed-off-by: Marc Zyngier <maz(a)kernel.org> Acked-by: Zenghui Yu <yuzenghui(a)huawei.com> Link: https://lore.kernel.org/r/20230713070657.3873244-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8b6096753740..d3dd05bbfe23 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -727,6 +727,8 @@ struct kvm_vcpu_arch { #define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5)) /* PMUSERENR for the guest EL0 is on physical CPU */ #define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6)) +/* WFI instruction trapped */ +#define IN_WFI __vcpu_single_flag(sflags, BIT(7)) /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a402ea5511f3..72dc53a75d1c 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -718,13 +718,15 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) */ preempt_disable(); kvm_vgic_vmcr_sync(vcpu); - vgic_v4_put(vcpu, true); + vcpu_set_flag(vcpu, IN_WFI); + vgic_v4_put(vcpu); preempt_enable(); kvm_vcpu_halt(vcpu); vcpu_clear_flag(vcpu, IN_WFIT); preempt_disable(); + vcpu_clear_flag(vcpu, IN_WFI); vgic_v4_load(vcpu); preempt_enable(); } @@ -792,7 +794,7 @@ static int check_vcpu_requests(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { /* The distributor enable bits were changed */ preempt_disable(); - vgic_v4_put(vcpu, false); + vgic_v4_put(vcpu); vgic_v4_load(vcpu); preempt_enable(); } diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index c3b8e132d599..3dfc8b84e03e 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -749,7 +749,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu) { struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3; - WARN_ON(vgic_v4_put(vcpu, false)); + WARN_ON(vgic_v4_put(vcpu)); vgic_v3_vmcr_sync(vcpu); diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c index c1c28fe680ba..339a55194b2c 100644 --- a/arch/arm64/kvm/vgic/vgic-v4.c +++ b/arch/arm64/kvm/vgic/vgic-v4.c @@ -336,14 +336,14 @@ void vgic_v4_teardown(struct kvm *kvm) its_vm->vpes = NULL; } -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db) +int vgic_v4_put(struct kvm_vcpu *vcpu) { struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe; if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident) return 0; - return its_make_vpe_non_resident(vpe, need_db); + return its_make_vpe_non_resident(vpe, !!vcpu_get_flag(vcpu, IN_WFI)); } int vgic_v4_load(struct kvm_vcpu *vcpu) @@ -354,6 +354,9 @@ int vgic_v4_load(struct kvm_vcpu *vcpu) if (!vgic_supports_direct_msis(vcpu->kvm) || vpe->resident) return 0; + if (vcpu_get_flag(vcpu, IN_WFI)) + return 0; + /* * Before making the VPE resident, make sure the redistributor * corresponding to our current CPU expects us here. See the diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 402b545959af..5b27f94d4fad 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -431,7 +431,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq, int vgic_v4_load(struct kvm_vcpu *vcpu); void vgic_v4_commit(struct kvm_vcpu *vcpu); -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db); +int vgic_v4_put(struct kvm_vcpu *vcpu); /* CPU HP callbacks */ void kvm_vgic_cpu_up(void);

5 months, 3 weeks

4
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FAILED: patch "[PATCH] iommu/dma: Trace bounce buffer usage when mapping buffers" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x a63c357b9fd56ad5fe64616f5b22835252c6a76a # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024012226-unmanned-marshy-5819@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: a63c357b9fd5 ("iommu/dma: Trace bounce buffer usage when mapping buffers") f316ba0a8814 ("dma-iommu: Check that swiotlb is active before trying to use it") a17e3026bc4d ("iommu: Move flush queue data into iommu_dma_cookie") f7f07484542f ("iommu/iova: Move flush queue code to iommu-dma") ea4d71bb5e3f ("iommu/iova: Consolidate flush queue code") 87f60cc65d24 ("iommu/vt-d: Use put_pages_list") 649ad9835a37 ("iommu/iova: Squash flush_cb abstraction") d5c383f2c98a ("iommu/iova: Squash entry_dtor abstraction") d7061627d701 ("iommu/iova: Fix race between FQ timeout and teardown") 2e727bffbe93 ("iommu/dma: Check CONFIG_SWIOTLB more broadly") 9b49bbc2c4df ("iommu/dma: Fold _swiotlb helpers into callers") ee9d4097cc14 ("iommu/dma: Skip extra sync during unmap w/swiotlb") 06e620345d54 ("iommu/dma: Fix arch_sync_dma for map") 08ae5d4a1ae9 ("iommu/dma: Fix sync_sg with swiotlb") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From a63c357b9fd56ad5fe64616f5b22835252c6a76a Mon Sep 17 00:00:00 2001 From: "Isaac J. Manjarres" <isaacmanjarres(a)google.com> Date: Fri, 8 Dec 2023 15:41:40 -0800 Subject: [PATCH] iommu/dma: Trace bounce buffer usage when mapping buffers When commit 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers") was introduced, it did not add the logic for tracing the bounce buffer usage from iommu_dma_map_page(). All of the users of swiotlb_tbl_map_single() trace their bounce buffer usage, except iommu_dma_map_page(). This makes it difficult to track SWIOTLB usage from that function. Thus, trace bounce buffer usage from iommu_dma_map_page(). Fixes: 82612d66d51d ("iommu: Allow the dma-iommu api to use bounce buffers") Cc: stable(a)vger.kernel.org # v5.15+ Cc: Tom Murphy <murphyt7(a)tcd.ie> Cc: Lu Baolu <baolu.lu(a)linux.intel.com> Cc: Saravana Kannan <saravanak(a)google.com> Signed-off-by: Isaac J. Manjarres <isaacmanjarres(a)google.com> Link: https://lore.kernel.org/r/20231208234141.2356157-1-isaacmanjarres@google.com Signed-off-by: Joerg Roedel <jroedel(a)suse.de> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 85163a83df2f..037fcf826407 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -29,6 +29,7 @@ #include <linux/spinlock.h> #include <linux/swiotlb.h> #include <linux/vmalloc.h> +#include <trace/events/swiotlb.h> #include "dma-iommu.h" @@ -1156,6 +1157,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, return DMA_MAPPING_ERROR; } + trace_swiotlb_bounced(dev, phys, size); + aligned_size = iova_align(iovad, size); phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size, iova_mask(iovad), dir, attrs);

6 months, 1 week

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[PATCH MANUALSEL 4.19 1/2] KVM: x86: Handle SRCU initialization failure during page track init

by Sasha Levin

From: Haimin Zhang <tcs_kernel(a)tencent.com> [ Upstream commit eb7511bf9182292ef1df1082d23039e856d1ddfb ] Check the return of init_srcu_struct(), which can fail due to OOM, when initializing the page track mechanism. Lack of checking leads to a NULL pointer deref found by a modified syzkaller. Reported-by: TCS Robot <tcs_robot(a)tencent.com> Signed-off-by: Haimin Zhang <tcs_kernel(a)tencent.com> Message-Id: <1630636626-12262-1-git-send-email-tcs_kernel(a)tencent.com> [Move the call towards the beginning of kvm_arch_init_vm. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- arch/x86/include/asm/kvm_page_track.h | 2 +- arch/x86/kvm/page_track.c | 4 ++-- arch/x86/kvm/x86.c | 7 ++++++- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/kvm_page_track.h b/arch/x86/include/asm/kvm_page_track.h index 172f9749dbb2..5986bd4aacd6 100644 --- a/arch/x86/include/asm/kvm_page_track.h +++ b/arch/x86/include/asm/kvm_page_track.h @@ -46,7 +46,7 @@ struct kvm_page_track_notifier_node { struct kvm_page_track_notifier_node *node); }; -void kvm_page_track_init(struct kvm *kvm); +int kvm_page_track_init(struct kvm *kvm); void kvm_page_track_cleanup(struct kvm *kvm); void kvm_page_track_free_memslot(struct kvm_memory_slot *free, diff --git a/arch/x86/kvm/page_track.c b/arch/x86/kvm/page_track.c index 3052a59a3065..1f6b0d9b0c85 100644 --- a/arch/x86/kvm/page_track.c +++ b/arch/x86/kvm/page_track.c @@ -169,13 +169,13 @@ void kvm_page_track_cleanup(struct kvm *kvm) cleanup_srcu_struct(&head->track_srcu); } -void kvm_page_track_init(struct kvm *kvm) +int kvm_page_track_init(struct kvm *kvm) { struct kvm_page_track_notifier_head *head; head = &kvm->arch.track_notifier_head; - init_srcu_struct(&head->track_srcu); INIT_HLIST_HEAD(&head->track_notifier_list); + return init_srcu_struct(&head->track_srcu); } /* diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 417abc9ba1ad..70cb18f89029 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9039,9 +9039,15 @@ void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { + int ret; + if (type) return -EINVAL; + ret = kvm_page_track_init(kvm); + if (ret) + return ret; + INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list); INIT_LIST_HEAD(&kvm->arch.active_mmu_pages); INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages); @@ -9068,7 +9074,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); kvm_hv_init_vm(kvm); - kvm_page_track_init(kvm); kvm_mmu_init_vm(kvm); if (kvm_x86_ops->vm_init) -- 2.33.0

6 months, 2 weeks

4
4
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FAILED: patch "[PATCH] KVM: x86: Clear "has_error_code", not "error_code", for RM" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 6c41468c7c12d74843bb414fc00307ea8a6318c3 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041135-yippee-shabby-b9ad@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: 6c41468c7c12 ("KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection") d4963e319f1f ("KVM: x86: Make kvm_queued_exception a properly named, visible struct") 6ad75c5c99f7 ("KVM: x86: Rename kvm_x86_ops.queue_exception to inject_exception") 5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)") 8d178f460772 ("KVM: nVMX: Treat General Detect #DB (DR7.GD=1) as fault-like") eba9799b5a6e ("KVM: VMX: Drop bits 31:16 when shoving exception error code into VMCS") a61d7c5432ac ("KVM: x86: Trace re-injected exceptions") 6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction") 3741aec4c38f ("KVM: SVM: Stuff next_rip on emulated INT3 injection if NRIPS is supported") cd9e6da8048c ("KVM: SVM: Unwind "speculative" RIP advancement if INTn injection "fails"") 00f08d99dd7d ("KVM: nSVM: Sync next_rip field from vmcb12 to vmcb02") 9bd1f0efa859 ("KVM: nVMX: Clear IDT vectoring on nested VM-Exit for double/triple fault") c3634d25fbee ("KVM: nVMX: Leave most VM-Exit info fields unmodified on failed VM-Entry") 1d5a1b5860ed ("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running") db663af4a001 ("kvm: x86: SVM: use vmcb* instead of svm->vmcb where it makes sense") b9f3973ab3a8 ("KVM: x86: nSVM: implement nested VMLOAD/VMSAVE") 23e5092b6e2a ("KVM: SVM: Rename hook implementations to conform to kvm_x86_ops' names") e27bc0440ebd ("KVM: x86: Rename kvm_x86_ops pointers to align w/ preferred vendor names") 068f7ea61895 ("KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch") e1779c2714c3 ("KVM: x86: nSVM: fix potential NULL derefernce on nested migration") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 6c41468c7c12d74843bb414fc00307ea8a6318c3 Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Wed, 22 Mar 2023 07:32:59 -0700 Subject: [PATCH] KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection When injecting an exception into a vCPU in Real Mode, suppress the error code by clearing the flag that tracks whether the error code is valid, not by clearing the error code itself. The "typo" was introduced by recent fix for SVM's funky Paged Real Mode. Opportunistically hoist the logic above the tracepoint so that the trace is coherent with respect to what is actually injected (this was also the behavior prior to the buggy commit). Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.") Cc: stable(a)vger.kernel.org Cc: Maxim Levitsky <mlevitsk(a)redhat.com> Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-Id: <20230322143300.2209476-2-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 45017576ad5e..7d6f98b7635f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9908,13 +9908,20 @@ int kvm_check_nested_events(struct kvm_vcpu *vcpu) static void kvm_inject_exception(struct kvm_vcpu *vcpu) { + /* + * Suppress the error code if the vCPU is in Real Mode, as Real Mode + * exceptions don't report error codes. The presence of an error code + * is carried with the exception and only stripped when the exception + * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do + * report an error code despite the CPU being in Real Mode. + */ + vcpu->arch.exception.has_error_code &= is_protmode(vcpu); + trace_kvm_inj_exception(vcpu->arch.exception.vector, vcpu->arch.exception.has_error_code, vcpu->arch.exception.error_code, vcpu->arch.exception.injected); - if (vcpu->arch.exception.error_code && !is_protmode(vcpu)) - vcpu->arch.exception.error_code = false; static_call(kvm_x86_inject_exception)(vcpu); }

7 months

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FAILED: patch "[PATCH] ext4: fix bug_on in __es_tree_search" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From d36f6ed761b53933b0b4126486c10d3da7751e7f Mon Sep 17 00:00:00 2001 From: Baokun Li <libaokun1(a)huawei.com> Date: Wed, 18 May 2022 20:08:16 +0800 Subject: [PATCH] ext4: fix bug_on in __es_tree_search Hulk Robot reported a BUG_ON: ================================================================== kernel BUG at fs/ext4/extents_status.c:199! [...] RIP: 0010:ext4_es_end fs/ext4/extents_status.c:199 [inline] RIP: 0010:__es_tree_search+0x1e0/0x260 fs/ext4/extents_status.c:217 [...] Call Trace: ext4_es_cache_extent+0x109/0x340 fs/ext4/extents_status.c:766 ext4_cache_extents+0x239/0x2e0 fs/ext4/extents.c:561 ext4_find_extent+0x6b7/0xa20 fs/ext4/extents.c:964 ext4_ext_map_blocks+0x16b/0x4b70 fs/ext4/extents.c:4384 ext4_map_blocks+0xe26/0x19f0 fs/ext4/inode.c:567 ext4_getblk+0x320/0x4c0 fs/ext4/inode.c:980 ext4_bread+0x2d/0x170 fs/ext4/inode.c:1031 ext4_quota_read+0x248/0x320 fs/ext4/super.c:6257 v2_read_header+0x78/0x110 fs/quota/quota_v2.c:63 v2_check_quota_file+0x76/0x230 fs/quota/quota_v2.c:82 vfs_load_quota_inode+0x5d1/0x1530 fs/quota/dquot.c:2368 dquot_enable+0x28a/0x330 fs/quota/dquot.c:2490 ext4_quota_enable fs/ext4/super.c:6137 [inline] ext4_enable_quotas+0x5d7/0x960 fs/ext4/super.c:6163 ext4_fill_super+0xa7c9/0xdc00 fs/ext4/super.c:4754 mount_bdev+0x2e9/0x3b0 fs/super.c:1158 mount_fs+0x4b/0x1e4 fs/super.c:1261 [...] ================================================================== Above issue may happen as follows: ------------------------------------- ext4_fill_super ext4_enable_quotas ext4_quota_enable ext4_iget __ext4_iget ext4_ext_check_inode ext4_ext_check __ext4_ext_check ext4_valid_extent_entries Check for overlapping extents does't take effect dquot_enable vfs_load_quota_inode v2_check_quota_file v2_read_header ext4_quota_read ext4_bread ext4_getblk ext4_map_blocks ext4_ext_map_blocks ext4_find_extent ext4_cache_extents ext4_es_cache_extent ext4_es_cache_extent __es_tree_search ext4_es_end BUG_ON(es->es_lblk + es->es_len < es->es_lblk) The error ext4 extents is as follows: 0af3 0300 0400 0000 00000000 extent_header 00000000 0100 0000 12000000 extent1 00000000 0100 0000 18000000 extent2 02000000 0400 0000 14000000 extent3 In the ext4_valid_extent_entries function, if prev is 0, no error is returned even if lblock<=prev. This was intended to skip the check on the first extent, but in the error image above, prev=0+1-1=0 when checking the second extent, so even though lblock<=prev, the function does not return an error. As a result, bug_ON occurs in __es_tree_search and the system panics. To solve this problem, we only need to check that: 1. The lblock of the first extent is not less than 0. 2. The lblock of the next extent is not less than the next block of the previous extent. The same applies to extent_idx. Cc: stable(a)kernel.org Fixes: 5946d089379a ("ext4: check for overlapping extents in ext4_valid_extent_entries()") Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Baokun Li <libaokun1(a)huawei.com> Reviewed-by: Jan Kara <jack(a)suse.cz> Link: https://lore.kernel.org/r/20220518120816.1541863-1-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 474479ce76e0..c148bb97b527 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -372,7 +372,7 @@ static int ext4_valid_extent_entries(struct inode *inode, { unsigned short entries; ext4_lblk_t lblock = 0; - ext4_lblk_t prev = 0; + ext4_lblk_t cur = 0; if (eh->eh_entries == 0) return 1; @@ -396,11 +396,11 @@ static int ext4_valid_extent_entries(struct inode *inode, /* Check for overlapping extents */ lblock = le32_to_cpu(ext->ee_block); - if ((lblock <= prev) && prev) { + if (lblock < cur) { *pblk = ext4_ext_pblock(ext); return 0; } - prev = lblock + ext4_ext_get_actual_len(ext) - 1; + cur = lblock + ext4_ext_get_actual_len(ext); ext++; entries--; } @@ -420,13 +420,13 @@ static int ext4_valid_extent_entries(struct inode *inode, /* Check for overlapping index extents */ lblock = le32_to_cpu(ext_idx->ei_block); - if ((lblock <= prev) && prev) { + if (lblock < cur) { *pblk = ext4_idx_pblock(ext_idx); return 0; } ext_idx++; entries--; - prev = lblock; + cur = lblock + 1; } } return 1;

7 months, 2 weeks

2
1
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[PATCH 1/2] SELinux: Fix lsm_get_self_attr()

by Mickaël Salaün

selinux_lsm_getattr() may not initialize the value's pointer in some case. As for proc_pid_attr_read(), initialize this pointer to NULL in selinux_getselfattr() to avoid an UAF in the kfree() call. Cc: Casey Schaufler <casey(a)schaufler-ca.com> Cc: Paul Moore <paul(a)paul-moore.com> Cc: stable(a)vger.kernel.org Fixes: 762c934317e6 ("SELinux: Add selfattr hooks") Signed-off-by: Mickaël Salaün <mic(a)digikod.net> --- security/selinux/hooks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a6bf90ace84c..338b023a8c3e 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6559,7 +6559,7 @@ static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx, size_t *size, u32 flags) { int rc; - char *val; + char *val = NULL; int val_len; val_len = selinux_lsm_getattr(attr, current, &val); -- 2.43.0

7 months, 2 weeks

3
16
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FAILED: patch "[PATCH] KVM: x86: Clear "has_error_code", not "error_code", for RM" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 6c41468c7c12d74843bb414fc00307ea8a6318c3 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041134-curvature-campsite-e51b@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: 6c41468c7c12 ("KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection") d4963e319f1f ("KVM: x86: Make kvm_queued_exception a properly named, visible struct") 6ad75c5c99f7 ("KVM: x86: Rename kvm_x86_ops.queue_exception to inject_exception") 5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)") 8d178f460772 ("KVM: nVMX: Treat General Detect #DB (DR7.GD=1) as fault-like") eba9799b5a6e ("KVM: VMX: Drop bits 31:16 when shoving exception error code into VMCS") a61d7c5432ac ("KVM: x86: Trace re-injected exceptions") 6ef88d6e36c2 ("KVM: SVM: Re-inject INT3/INTO instead of retrying the instruction") 3741aec4c38f ("KVM: SVM: Stuff next_rip on emulated INT3 injection if NRIPS is supported") cd9e6da8048c ("KVM: SVM: Unwind "speculative" RIP advancement if INTn injection "fails"") 00f08d99dd7d ("KVM: nSVM: Sync next_rip field from vmcb12 to vmcb02") 9bd1f0efa859 ("KVM: nVMX: Clear IDT vectoring on nested VM-Exit for double/triple fault") c3634d25fbee ("KVM: nVMX: Leave most VM-Exit info fields unmodified on failed VM-Entry") 1d5a1b5860ed ("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running") db663af4a001 ("kvm: x86: SVM: use vmcb* instead of svm->vmcb where it makes sense") b9f3973ab3a8 ("KVM: x86: nSVM: implement nested VMLOAD/VMSAVE") 23e5092b6e2a ("KVM: SVM: Rename hook implementations to conform to kvm_x86_ops' names") e27bc0440ebd ("KVM: x86: Rename kvm_x86_ops pointers to align w/ preferred vendor names") 068f7ea61895 ("KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch") e1779c2714c3 ("KVM: x86: nSVM: fix potential NULL derefernce on nested migration") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 6c41468c7c12d74843bb414fc00307ea8a6318c3 Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Wed, 22 Mar 2023 07:32:59 -0700 Subject: [PATCH] KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection When injecting an exception into a vCPU in Real Mode, suppress the error code by clearing the flag that tracks whether the error code is valid, not by clearing the error code itself. The "typo" was introduced by recent fix for SVM's funky Paged Real Mode. Opportunistically hoist the logic above the tracepoint so that the trace is coherent with respect to what is actually injected (this was also the behavior prior to the buggy commit). Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.") Cc: stable(a)vger.kernel.org Cc: Maxim Levitsky <mlevitsk(a)redhat.com> Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-Id: <20230322143300.2209476-2-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 45017576ad5e..7d6f98b7635f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9908,13 +9908,20 @@ int kvm_check_nested_events(struct kvm_vcpu *vcpu) static void kvm_inject_exception(struct kvm_vcpu *vcpu) { + /* + * Suppress the error code if the vCPU is in Real Mode, as Real Mode + * exceptions don't report error codes. The presence of an error code + * is carried with the exception and only stripped when the exception + * is injected as intercepted #PF VM-Exits for AMD's Paged Real Mode do + * report an error code despite the CPU being in Real Mode. + */ + vcpu->arch.exception.has_error_code &= is_protmode(vcpu); + trace_kvm_inj_exception(vcpu->arch.exception.vector, vcpu->arch.exception.has_error_code, vcpu->arch.exception.error_code, vcpu->arch.exception.injected); - if (vcpu->arch.exception.error_code && !is_protmode(vcpu)) - vcpu->arch.exception.error_code = false; static_call(kvm_x86_inject_exception)(vcpu); }

7 months, 2 weeks

3
2
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