April 2025 - Linux-stable-mirror

FAILED: patch "[PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-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-6.6.y git checkout FETCH_HEAD git cherry-pick -x f1fb088d9cecde5c3066d8ff8846789667519b7d # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042805-occupier-decibel-a03d@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From f1fb088d9cecde5c3066d8ff8846789667519b7d Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Fri, 4 Apr 2025 12:38:19 -0700 Subject: [PATCH] KVM: x86: Take irqfds.lock when adding/deleting IRQ bypass producer Take irqfds.lock when adding/deleting an IRQ bypass producer to ensure irqfd->producer isn't modified while kvm_irq_routing_update() is running. The only lock held when a producer is added/removed is irqbypass's mutex. Fixes: 872768800652 ("KVM: x86: select IRQ_BYPASS_MANAGER") Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-ID: <20250404193923.1413163-5-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 9c98b77b7dc1..a6829a370e6a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13561,15 +13561,22 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, { struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; int ret; - irqfd->producer = prod; kvm_arch_start_assignment(irqfd->kvm); + + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = prod; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 1); if (ret) kvm_arch_end_assignment(irqfd->kvm); + spin_unlock_irq(&kvm->irqfds.lock); + + return ret; } @@ -13579,9 +13586,9 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, int ret; struct kvm_kernel_irqfd *irqfd = container_of(cons, struct kvm_kernel_irqfd, consumer); + struct kvm *kvm = irqfd->kvm; WARN_ON(irqfd->producer != prod); - irqfd->producer = NULL; /* * When producer of consumer is unregistered, we change back to @@ -13589,12 +13596,18 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, * when the irq is masked/disabled or the consumer side (KVM * int this case doesn't want to receive the interrupts. */ + spin_lock_irq(&kvm->irqfds.lock); + irqfd->producer = NULL; + ret = kvm_x86_call(pi_update_irte)(irqfd->kvm, prod->irq, irqfd->gsi, 0); if (ret) printk(KERN_INFO "irq bypass consumer (token %p) unregistration" " fails: %d\n", irqfd->consumer.token, ret); + spin_unlock_irq(&kvm->irqfds.lock); + + kvm_arch_end_assignment(irqfd->kvm); }

2 months, 1 week

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FAILED: patch "[PATCH] KVM: x86: Reset IRTE to host control if *new* route isn't" 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>. 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-5.4.y git checkout FETCH_HEAD git cherry-pick -x 9bcac97dc42d2f4da8229d18feb0fe2b1ce523a2 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042851-tasting-pushup-f190@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 9bcac97dc42d2f4da8229d18feb0fe2b1ce523a2 Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Fri, 4 Apr 2025 12:38:17 -0700 Subject: [PATCH] KVM: x86: Reset IRTE to host control if *new* route isn't postable Restore an IRTE back to host control (remapped or posted MSI mode) if the *new* GSI route prevents posting the IRQ directly to a vCPU, regardless of the GSI routing type. Updating the IRTE if and only if the new GSI is an MSI results in KVM leaving an IRTE posting to a vCPU. The dangling IRTE can result in interrupts being incorrectly delivered to the guest, and in the worst case scenario can result in use-after-free, e.g. if the VM is torn down, but the underlying host IRQ isn't freed. Fixes: efc644048ecd ("KVM: x86: Update IRTE for posted-interrupts") Fixes: 411b44ba80ab ("svm: Implements update_pi_irte hook to setup posted interrupt") Cc: stable(a)vger.kernel.org Signed-off-by: Sean Christopherson <seanjc(a)google.com> Message-ID: <20250404193923.1413163-3-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index a961e6e67050..8e09f6ae98fd 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -896,6 +896,7 @@ int avic_pi_update_irte(struct kvm *kvm, unsigned int host_irq, { struct kvm_kernel_irq_routing_entry *e; struct kvm_irq_routing_table *irq_rt; + bool enable_remapped_mode = true; int idx, ret = 0; if (!kvm_arch_has_assigned_device(kvm) || !kvm_arch_has_irq_bypass()) @@ -932,6 +933,8 @@ int avic_pi_update_irte(struct kvm *kvm, unsigned int host_irq, kvm_vcpu_apicv_active(&svm->vcpu)) { struct amd_iommu_pi_data pi; + enable_remapped_mode = false; + /* Try to enable guest_mode in IRTE */ pi.base = __sme_set(page_to_phys(svm->avic_backing_page) & AVIC_HPA_MASK); @@ -950,33 +953,6 @@ int avic_pi_update_irte(struct kvm *kvm, unsigned int host_irq, */ if (!ret && pi.is_guest_mode) svm_ir_list_add(svm, &pi); - } else { - /* Use legacy mode in IRTE */ - struct amd_iommu_pi_data pi; - - /** - * Here, pi is used to: - * - Tell IOMMU to use legacy mode for this interrupt. - * - Retrieve ga_tag of prior interrupt remapping data. - */ - pi.prev_ga_tag = 0; - pi.is_guest_mode = false; - ret = irq_set_vcpu_affinity(host_irq, &pi); - - /** - * Check if the posted interrupt was previously - * setup with the guest_mode by checking if the ga_tag - * was cached. If so, we need to clean up the per-vcpu - * ir_list. - */ - if (!ret && pi.prev_ga_tag) { - int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag); - struct kvm_vcpu *vcpu; - - vcpu = kvm_get_vcpu_by_id(kvm, id); - if (vcpu) - svm_ir_list_del(to_svm(vcpu), &pi); - } } if (!ret && svm) { @@ -992,6 +968,34 @@ int avic_pi_update_irte(struct kvm *kvm, unsigned int host_irq, } ret = 0; + if (enable_remapped_mode) { + /* Use legacy mode in IRTE */ + struct amd_iommu_pi_data pi; + + /** + * Here, pi is used to: + * - Tell IOMMU to use legacy mode for this interrupt. + * - Retrieve ga_tag of prior interrupt remapping data. + */ + pi.prev_ga_tag = 0; + pi.is_guest_mode = false; + ret = irq_set_vcpu_affinity(host_irq, &pi); + + /** + * Check if the posted interrupt was previously + * setup with the guest_mode by checking if the ga_tag + * was cached. If so, we need to clean up the per-vcpu + * ir_list. + */ + if (!ret && pi.prev_ga_tag) { + int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag); + struct kvm_vcpu *vcpu; + + vcpu = kvm_get_vcpu_by_id(kvm, id); + if (vcpu) + svm_ir_list_del(to_svm(vcpu), &pi); + } + } out: srcu_read_unlock(&kvm->irq_srcu, idx); return ret; diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c index 51116fe69a50..d70e5b90087d 100644 --- a/arch/x86/kvm/vmx/posted_intr.c +++ b/arch/x86/kvm/vmx/posted_intr.c @@ -297,6 +297,7 @@ int vmx_pi_update_irte(struct kvm *kvm, unsigned int host_irq, { struct kvm_kernel_irq_routing_entry *e; struct kvm_irq_routing_table *irq_rt; + bool enable_remapped_mode = true; struct kvm_lapic_irq irq; struct kvm_vcpu *vcpu; struct vcpu_data vcpu_info; @@ -335,21 +336,8 @@ int vmx_pi_update_irte(struct kvm *kvm, unsigned int host_irq, kvm_set_msi_irq(kvm, e, &irq); if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu) || - !kvm_irq_is_postable(&irq)) { - /* - * Make sure the IRTE is in remapped mode if - * we don't handle it in posted mode. - */ - ret = irq_set_vcpu_affinity(host_irq, NULL); - if (ret < 0) { - printk(KERN_INFO - "failed to back to remapped mode, irq: %u\n", - host_irq); - goto out; - } - + !kvm_irq_is_postable(&irq)) continue; - } vcpu_info.pi_desc_addr = __pa(vcpu_to_pi_desc(vcpu)); vcpu_info.vector = irq.vector; @@ -357,11 +345,12 @@ int vmx_pi_update_irte(struct kvm *kvm, unsigned int host_irq, trace_kvm_pi_irte_update(host_irq, vcpu->vcpu_id, e->gsi, vcpu_info.vector, vcpu_info.pi_desc_addr, set); - if (set) - ret = irq_set_vcpu_affinity(host_irq, &vcpu_info); - else - ret = irq_set_vcpu_affinity(host_irq, NULL); + if (!set) + continue; + enable_remapped_mode = false; + + ret = irq_set_vcpu_affinity(host_irq, &vcpu_info); if (ret < 0) { printk(KERN_INFO "%s: failed to update PI IRTE\n", __func__); @@ -369,6 +358,9 @@ int vmx_pi_update_irte(struct kvm *kvm, unsigned int host_irq, } } + if (enable_remapped_mode) + ret = irq_set_vcpu_affinity(host_irq, NULL); + ret = 0; out: srcu_read_unlock(&kvm->irq_srcu, idx);

2 months, 1 week

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FAILED: patch "[PATCH] xen-netfront: handle NULL returned by" 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 cc3628dcd851ddd8d418bf0c897024b4621ddc92 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025042858-guacamole-ozone-ac80@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From cc3628dcd851ddd8d418bf0c897024b4621ddc92 Mon Sep 17 00:00:00 2001 From: Alexey Nepomnyashih <sdl(a)nppct.ru> Date: Thu, 17 Apr 2025 12:21:17 +0000 Subject: [PATCH] xen-netfront: handle NULL returned by xdp_convert_buff_to_frame() The function xdp_convert_buff_to_frame() may return NULL if it fails to correctly convert the XDP buffer into an XDP frame due to memory constraints, internal errors, or invalid data. Failing to check for NULL may lead to a NULL pointer dereference if the result is used later in processing, potentially causing crashes, data corruption, or undefined behavior. On XDP redirect failure, the associated page must be released explicitly if it was previously retained via get_page(). Failing to do so may result in a memory leak, as the pages reference count is not decremented. Cc: stable(a)vger.kernel.org # v5.9+ Fixes: 6c5aa6fc4def ("xen networking: add basic XDP support for xen-netfront") Signed-off-by: Alexey Nepomnyashih <sdl(a)nppct.ru> Link: https://patch.msgid.link/20250417122118.1009824-1-sdl@nppct.ru Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index fc52d5c4c69b..5091e1fa4a0d 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -985,20 +985,27 @@ static u32 xennet_run_xdp(struct netfront_queue *queue, struct page *pdata, act = bpf_prog_run_xdp(prog, xdp); switch (act) { case XDP_TX: - get_page(pdata); xdpf = xdp_convert_buff_to_frame(xdp); - err = xennet_xdp_xmit(queue->info->netdev, 1, &xdpf, 0); - if (unlikely(!err)) - xdp_return_frame_rx_napi(xdpf); - else if (unlikely(err < 0)) + if (unlikely(!xdpf)) { trace_xdp_exception(queue->info->netdev, prog, act); + break; + } + get_page(pdata); + err = xennet_xdp_xmit(queue->info->netdev, 1, &xdpf, 0); + if (unlikely(err <= 0)) { + if (err < 0) + trace_xdp_exception(queue->info->netdev, prog, act); + xdp_return_frame_rx_napi(xdpf); + } break; case XDP_REDIRECT: get_page(pdata); err = xdp_do_redirect(queue->info->netdev, xdp, prog); *need_xdp_flush = true; - if (unlikely(err)) + if (unlikely(err)) { trace_xdp_exception(queue->info->netdev, prog, act); + xdp_return_buff(xdp); + } break; case XDP_PASS: case XDP_DROP:

2 months, 1 week

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GCC 15 and stable kernels

by Chris Clayton

Hi Greg, I've built the four stable kernels that were released on 25 April. I found that to successfully build with GCC-15, each of them required backports of one or both of two upstream commits. Those commits are: Title Commit Author nonstring 9d7a0577c9db35c4cc52db90bc415ea248446472 Linus gnu11 b3bee1e7c3f2b1b77182302c7b2131c804175870 Alexey Dobriyan 6.14.4 and 6.12.25 required only nonstring. 6.6.87 required only gnu11, 6.1.35 required both. Additionally, chasing down why my new Bluetooth mouse doesn't work, I also had cause to build 5.15.180 and found that it needed gnull. I have TO dash out now, but I could send you a zip archive of the patches later today, if that would help. Chris

2 months, 1 week

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Re: FW: Wireless speed regression issue with >6.12.12/6.13.x + firmware update for mediatek MT7925

by Mingyen Hsieh (謝明諺)

Hi, Thanks for reporting this issue. We will conduct testing again. And it is already known that the patch added in 6.12.13 does have some issues, but we have also submitted new patches to fix. Currently, these patches are in the maintainer’s tree. It should soon be included in 6.14 and then ported Back to 6.12.x and 6.13.x. Perhaps you can test the driver from here: https://github.com/nbd168/wireless and apply this patch: https://patchwork.kernel.org/project/linux-wireless/patch/20250317011724.33… Thanks Best Regards, Yen.

2 months, 1 week

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[PATCH 6.6.y] x86/pvh: Call C code via the kernel virtual mapping

by Jason Andryuk

From: Ard Biesheuvel <ardb(a)kernel.org> [ Upstream commit e8fbc0d9cab6c1ee6403f42c0991b0c1d5dbc092 ] Calling C code via a different mapping than it was linked at is problematic, because the compiler assumes that RIP-relative and absolute symbol references are interchangeable. GCC in particular may use RIP-relative per-CPU variable references even when not using -fpic. So call xen_prepare_pvh() via its kernel virtual mapping on x86_64, so that those RIP-relative references produce the correct values. This matches the pre-existing behavior for i386, which also invokes xen_prepare_pvh() via the kernel virtual mapping before invoking startup_32 with paging disabled again. Fixes: 7243b93345f7 ("xen/pvh: Bootstrap PVH guest") Tested-by: Jason Andryuk <jason.andryuk(a)amd.com> Reviewed-by: Jason Andryuk <jason.andryuk(a)amd.com> Signed-off-by: Ard Biesheuvel <ardb(a)kernel.org> Message-ID: <20241009160438.3884381-8-ardb+git(a)google.com> Signed-off-by: Juergen Gross <jgross(a)suse.com> [ Stable context update ] Signed-off-by: Jason Andryuk <jason.andryuk(a)amd.com> --- Stable backport for 6.6. This was added to 6.1, 5.15, and 5.10, but it is also needed for 6.6. Direct cherry-pick needed context fixups, which are made here. This upstream commit was previously included in stable, but with the pre-req of b464b461d27d ("x86/pvh: Set phys_base when calling xen_prepare_pvh()"). Both were subsequently reverted as b464b461d27d caused regressions. This backport, e8fbc0d9cab6, in isolation is correct. This fixes a regression introduced by the backport of upstream commit b4845bb6383821a9516ce30af3a27dc873e37fd4 ("x86/xen: add central hypercall functions") b4845bb63838 adds a comparison between rip-relative xen_hypercall_amd() and kernel virtual address of xen_hypercall_amd() to determine whether to use the AMD or Intel variant. When running from the identity mapped address, the comparison always fail. The leads to calling xen_hypercall_intel(), even on AMD processors, which faults and halts boot. This affects PVH dom0 - domU doesn't seem to be affected. This patch performs the rip-relative mapping from the kernel virtual mapping, so the values can be properly compared. --- arch/x86/platform/pvh/head.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S index c4365a05ab83..fc46b4dfbd74 100644 --- a/arch/x86/platform/pvh/head.S +++ b/arch/x86/platform/pvh/head.S @@ -100,7 +100,12 @@ SYM_CODE_START_LOCAL(pvh_start_xen) xor %edx, %edx wrmsr - call xen_prepare_pvh + /* Call xen_prepare_pvh() via the kernel virtual mapping */ + leaq xen_prepare_pvh(%rip), %rax + subq phys_base(%rip), %rax + addq $__START_KERNEL_map, %rax + ANNOTATE_RETPOLINE_SAFE + call *%rax /* startup_64 expects boot_params in %rsi. */ mov $_pa(pvh_bootparams), %rsi -- 2.49.0

2 months, 1 week

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[PATCH] drm/amdgpu: check a user-provided number of BOs in list

by Alex Deucher

From: Denis Arefev <arefev(a)swemel.ru> The user can set any value to the variable ‘bo_number’, via the ioctl command DRM_IOCTL_AMDGPU_BO_LIST. This will affect the arithmetic expression ‘in->bo_number * in->bo_info_size’, which is prone to overflow. Add a valid value check. Found by Linux Verification Center (linuxtesting.org) with SVACE. v2: drop 0 check as a BO list of 0 is valid (Alex) Fixes: 964d0fbf6301 ("drm/amdgpu: Allow to create BO lists in CS ioctl v3") Cc: stable(a)vger.kernel.org Reviewed-by: Christian König <christian.koenig(a)amd.com> Signed-off-by: Denis Arefev <arefev(a)swemel.ru> Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c index 702f6610d0243..81875df6295bb 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c @@ -189,6 +189,9 @@ int amdgpu_bo_create_list_entry_array(struct drm_amdgpu_bo_list_in *in, struct drm_amdgpu_bo_list_entry *info; int r; + if (in->bo_number > USHRT_MAX) + return -EINVAL; + info = kvmalloc_array(in->bo_number, info_size, GFP_KERNEL); if (!info) return -ENOMEM; -- 2.49.0

2 months, 1 week

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[PATCH 2/2] fbdev: Fix fb_ser_var to prevent null-ptr-deref in fb_videomode_to_var

by Murad Masimov

If fb_add_videomode() in fb_set_var() fails to allocate memory for fb_videomode, later it may lead to a null-ptr dereference in fb_videomode_to_var(), as the fb_info is registered while not having the mode in modelist that is expected to be there, i.e. the one that is described in fb_info->var. ================================================================ general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901 Call Trace: display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929 fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071 resize_screen drivers/tty/vt/vt.c:1176 [inline] vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263 fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720 fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776 do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128 fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 ================================================================ The reason is that fb_info->var is being modified in fb_set_var(), and then fb_videomode_to_var() is called. If it fails to add the mode to fb_info->modelist, fb_set_var() returns error, but does not restore the old value of fb_info->var. Restore fb_info->var on fail the same way it is done earlier in the function. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable(a)vger.kernel.org Signed-off-by: Murad Masimov <m.masimov(a)mt-integration.ru> --- drivers/video/fbdev/core/fbmem.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index e1557d80768f..eca2498f2436 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -328,8 +328,10 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var) !list_empty(&info->modelist)) ret = fb_add_videomode(&mode, &info->modelist); - if (ret) + if (ret) { + info->var = old_var; return ret; + } event.info = info; event.data = &mode; -- 2.39.2

2 months, 1 week

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[PATCH 1/2] fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var

by Murad Masimov

If fb_add_videomode() in do_register_framebuffer() fails to allocate memory for fb_videomode, it will later lead to a null-ptr dereference in fb_videomode_to_var(), as the fb_info is registered while not having the mode in modelist that is expected to be there, i.e. the one that is described in fb_info->var. ================================================================ general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901 Call Trace: display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929 fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071 resize_screen drivers/tty/vt/vt.c:1176 [inline] vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263 fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720 fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776 do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128 fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 ================================================================ Even though fbcon_init() checks beforehand if fb_match_mode() in var_to_display() fails, it can not prevent the panic because fbcon_init() does not return error code. Considering this and the comment in the code about fb_match_mode() returning NULL - "This should not happen" - it is better to prevent registering the fb_info if its mode was not set successfully. Also move fb_add_videomode() closer to the beginning of do_register_framebuffer() to avoid having to do the cleanup on fail. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable(a)vger.kernel.org Signed-off-by: Murad Masimov <m.masimov(a)mt-integration.ru> --- drivers/video/fbdev/core/fbmem.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 3c568cff2913..e1557d80768f 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -388,7 +388,7 @@ static int fb_check_foreignness(struct fb_info *fi) static int do_register_framebuffer(struct fb_info *fb_info) { - int i; + int i, err = 0; struct fb_videomode mode; if (fb_check_foreignness(fb_info)) @@ -397,10 +397,18 @@ static int do_register_framebuffer(struct fb_info *fb_info) if (num_registered_fb == FB_MAX) return -ENXIO; - num_registered_fb++; for (i = 0 ; i < FB_MAX; i++) if (!registered_fb[i]) break; + + if (!fb_info->modelist.prev || !fb_info->modelist.next) + INIT_LIST_HEAD(&fb_info->modelist); + + fb_var_to_videomode(&mode, &fb_info->var); + err = fb_add_videomode(&mode, &fb_info->modelist); + if (err < 0) + return err; + fb_info->node = i; refcount_set(&fb_info->count, 1); mutex_init(&fb_info->lock); @@ -426,16 +434,12 @@ static int do_register_framebuffer(struct fb_info *fb_info) if (bitmap_empty(fb_info->pixmap.blit_y, FB_MAX_BLIT_HEIGHT)) bitmap_fill(fb_info->pixmap.blit_y, FB_MAX_BLIT_HEIGHT); - if (!fb_info->modelist.prev || !fb_info->modelist.next) - INIT_LIST_HEAD(&fb_info->modelist); - if (fb_info->skip_vt_switch) pm_vt_switch_required(fb_info->device, false); else pm_vt_switch_required(fb_info->device, true); - fb_var_to_videomode(&mode, &fb_info->var); - fb_add_videomode(&mode, &fb_info->modelist); + num_registered_fb++; registered_fb[i] = fb_info; #ifdef CONFIG_GUMSTIX_AM200EPD -- 2.39.2

2 months, 1 week

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[PATCH v2] drm/amdgpu: check a user-provided number of BOs in list

by Denis Arefev

The user can set any value to the variable ‘bo_number’, via the ioctl command DRM_IOCTL_AMDGPU_BO_LIST. This will affect the arithmetic expression ‘in->bo_number * in->bo_info_size’, which is prone to overflow. Add a valid value check. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 964d0fbf6301 ("drm/amdgpu: Allow to create BO lists in CS ioctl v3") Cc: stable(a)vger.kernel.org Signed-off-by: Denis Arefev <arefev(a)swemel.ru> --- V1 -> V2: Set a reasonable limit 'USHRT_MAX' for 'bo_number' it as Christian König <christian.koenig(a)amd.com> suggested drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c index 702f6610d024..85f7ee1e085d 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c @@ -189,6 +189,9 @@ int amdgpu_bo_create_list_entry_array(struct drm_amdgpu_bo_list_in *in, struct drm_amdgpu_bo_list_entry *info; int r; + if (!in->bo_number || in->bo_number > USHRT_MAX) + return -EINVAL; + info = kvmalloc_array(in->bo_number, info_size, GFP_KERNEL); if (!info) return -ENOMEM; -- 2.43.0

2 months, 1 week

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