Total
4165 CVE
| CVE | Vendors | Products | Updated | CVSS v3.1 |
|---|---|---|---|---|
| CVE-2024-36884 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Use the correct type in nvidia_smmu_context_fault() This was missed because of the function pointer indirection. nvidia_smmu_context_fault() is also installed as a irq function, and the 'void *' was changed to a struct arm_smmu_domain. Since the iommu_domain is embedded at a non-zero offset this causes nvidia_smmu_context_fault() to miscompute the offset. Fixup the types. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000120 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000107c9f000 [0000000000000120] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 1 PID: 47 Comm: kworker/u25:0 Not tainted 6.9.0-0.rc7.58.eln136.aarch64 #1 Hardware name: Unknown NVIDIA Jetson Orin NX/NVIDIA Jetson Orin NX, BIOS 3.1-32827747 03/19/2023 Workqueue: events_unbound deferred_probe_work_func pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : nvidia_smmu_context_fault+0x1c/0x158 lr : __free_irq+0x1d4/0x2e8 sp : ffff80008044b6f0 x29: ffff80008044b6f0 x28: ffff000080a60b18 x27: ffffd32b5172e970 x26: 0000000000000000 x25: ffff0000802f5aac x24: ffff0000802f5a30 x23: ffff0000802f5b60 x22: 0000000000000057 x21: 0000000000000000 x20: ffff0000802f5a00 x19: ffff000087d4cd80 x18: ffffffffffffffff x17: 6234362066666666 x16: 6630303078302d30 x15: ffff00008156d888 x14: 0000000000000000 x13: ffff0000801db910 x12: ffff00008156d6d0 x11: 0000000000000003 x10: ffff0000801db918 x9 : ffffd32b50f94d9c x8 : 1fffe0001032fda1 x7 : ffff00008197ed00 x6 : 000000000000000f x5 : 000000000000010e x4 : 000000000000010e x3 : 0000000000000000 x2 : ffffd32b51720cd8 x1 : ffff000087e6f700 x0 : 0000000000000057 Call trace: nvidia_smmu_context_fault+0x1c/0x158 __free_irq+0x1d4/0x2e8 free_irq+0x3c/0x80 devm_free_irq+0x64/0xa8 arm_smmu_domain_free+0xc4/0x158 iommu_domain_free+0x44/0xa0 iommu_deinit_device+0xd0/0xf8 __iommu_group_remove_device+0xcc/0xe0 iommu_bus_notifier+0x64/0xa8 notifier_call_chain+0x78/0x148 blocking_notifier_call_chain+0x4c/0x90 bus_notify+0x44/0x70 device_del+0x264/0x3e8 pci_remove_bus_device+0x84/0x120 pci_remove_root_bus+0x5c/0xc0 dw_pcie_host_deinit+0x38/0xe0 tegra_pcie_config_rp+0xc0/0x1f0 tegra_pcie_dw_probe+0x34c/0x700 platform_probe+0x70/0xe8 really_probe+0xc8/0x3a0 __driver_probe_device+0x84/0x160 driver_probe_device+0x44/0x130 __device_attach_driver+0xc4/0x170 bus_for_each_drv+0x90/0x100 __device_attach+0xa8/0x1c8 device_initial_probe+0x1c/0x30 bus_probe_device+0xb0/0xc0 deferred_probe_work_func+0xbc/0x120 process_one_work+0x194/0x490 worker_thread+0x284/0x3b0 kthread+0xf4/0x108 ret_from_fork+0x10/0x20 Code: a9b97bfd 910003fd a9025bf5 f85a0035 (b94122a1) | ||||
| CVE-2024-36489 | 2 Linux, Redhat | 6 Linux Kernel, Enterprise Linux, Rhel Aus and 3 more | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: tls: fix missing memory barrier in tls_init In tls_init(), a write memory barrier is missing, and store-store reordering may cause NULL dereference in tls_{setsockopt,getsockopt}. CPU0 CPU1 ----- ----- // In tls_init() // In tls_ctx_create() ctx = kzalloc() ctx->sk_proto = READ_ONCE(sk->sk_prot) -(1) // In update_sk_prot() WRITE_ONCE(sk->sk_prot, tls_prots) -(2) // In sock_common_setsockopt() READ_ONCE(sk->sk_prot)->setsockopt() // In tls_{setsockopt,getsockopt}() ctx->sk_proto->setsockopt() -(3) In the above scenario, when (1) and (2) are reordered, (3) can observe the NULL value of ctx->sk_proto, causing NULL dereference. To fix it, we rely on rcu_assign_pointer() which implies the release barrier semantic. By moving rcu_assign_pointer() after ctx->sk_proto is initialized, we can ensure that ctx->sk_proto are visible when changing sk->sk_prot. | ||||
| CVE-2024-36479 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: fpga: bridge: add owner module and take its refcount The current implementation of the fpga bridge assumes that the low-level module registers a driver for the parent device and uses its owner pointer to take the module's refcount. This approach is problematic since it can lead to a null pointer dereference while attempting to get the bridge if the parent device does not have a driver. To address this problem, add a module owner pointer to the fpga_bridge struct and use it to take the module's refcount. Modify the function for registering a bridge to take an additional owner module parameter and rename it to avoid conflicts. Use the old function name for a helper macro that automatically sets the module that registers the bridge as the owner. This ensures compatibility with existing low-level control modules and reduces the chances of registering a bridge without setting the owner. Also, update the documentation to keep it consistent with the new interface for registering an fpga bridge. Other changes: opportunistically move put_device() from __fpga_bridge_get() to fpga_bridge_get() and of_fpga_bridge_get() to improve code clarity since the bridge device is taken in these functions. | ||||
| CVE-2024-36478 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues' Writing 'power' and 'submit_queues' concurrently will trigger kernel panic: Test script: modprobe null_blk nr_devices=0 mkdir -p /sys/kernel/config/nullb/nullb0 while true; do echo 1 > submit_queues; echo 4 > submit_queues; done & while true; do echo 1 > power; echo 0 > power; done Test result: BUG: kernel NULL pointer dereference, address: 0000000000000148 Oops: 0000 [#1] PREEMPT SMP RIP: 0010:__lock_acquire+0x41d/0x28f0 Call Trace: <TASK> lock_acquire+0x121/0x450 down_write+0x5f/0x1d0 simple_recursive_removal+0x12f/0x5c0 blk_mq_debugfs_unregister_hctxs+0x7c/0x100 blk_mq_update_nr_hw_queues+0x4a3/0x720 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_submit_queues_store+0x79/0xf0 [null_blk] configfs_write_iter+0x119/0x1e0 vfs_write+0x326/0x730 ksys_write+0x74/0x150 This is because del_gendisk() can concurrent with blk_mq_update_nr_hw_queues(): nullb_device_power_store nullb_apply_submit_queues null_del_dev del_gendisk nullb_update_nr_hw_queues if (!dev->nullb) // still set while gendisk is deleted return 0 blk_mq_update_nr_hw_queues dev->nullb = NULL Fix this problem by resuing the global mutex to protect nullb_device_power_store() and nullb_update_nr_hw_queues() from configfs. | ||||
| CVE-2024-36476 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: RDMA/rtrs: Ensure 'ib_sge list' is accessible Move the declaration of the 'ib_sge list' variable outside the 'always_invalidate' block to ensure it remains accessible for use throughout the function. Previously, 'ib_sge list' was declared within the 'always_invalidate' block, limiting its accessibility, then caused a 'BUG: kernel NULL pointer dereference'[1]. ? __die_body.cold+0x19/0x27 ? page_fault_oops+0x15a/0x2d0 ? search_module_extables+0x19/0x60 ? search_bpf_extables+0x5f/0x80 ? exc_page_fault+0x7e/0x180 ? asm_exc_page_fault+0x26/0x30 ? memcpy_orig+0xd5/0x140 rxe_mr_copy+0x1c3/0x200 [rdma_rxe] ? rxe_pool_get_index+0x4b/0x80 [rdma_rxe] copy_data+0xa5/0x230 [rdma_rxe] rxe_requester+0xd9b/0xf70 [rdma_rxe] ? finish_task_switch.isra.0+0x99/0x2e0 rxe_sender+0x13/0x40 [rdma_rxe] do_task+0x68/0x1e0 [rdma_rxe] process_one_work+0x177/0x330 worker_thread+0x252/0x390 ? __pfx_worker_thread+0x10/0x10 This change ensures the variable is available for subsequent operations that require it. [1] https://lore.kernel.org/linux-rdma/[email protected]/ | ||||
| CVE-2024-36281 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Use mlx5_ipsec_rx_status_destroy to correctly delete status rules rx_create no longer allocates a modify_hdr instance that needs to be cleaned up. The mlx5_modify_header_dealloc call will lead to a NULL pointer dereference. A leak in the rules also previously occurred since there are now two rules populated related to status. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 109907067 P4D 109907067 PUD 116890067 PMD 0 Oops: 0000 [#1] SMP CPU: 1 PID: 484 Comm: ip Not tainted 6.9.0-rc2-rrameshbabu+ #254 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Arch Linux 1.16.3-1-1 04/01/2014 RIP: 0010:mlx5_modify_header_dealloc+0xd/0x70 <snip> Call Trace: <TASK> ? show_regs+0x60/0x70 ? __die+0x24/0x70 ? page_fault_oops+0x15f/0x430 ? free_to_partial_list.constprop.0+0x79/0x150 ? do_user_addr_fault+0x2c9/0x5c0 ? exc_page_fault+0x63/0x110 ? asm_exc_page_fault+0x27/0x30 ? mlx5_modify_header_dealloc+0xd/0x70 rx_create+0x374/0x590 rx_add_rule+0x3ad/0x500 ? rx_add_rule+0x3ad/0x500 ? mlx5_cmd_exec+0x2c/0x40 ? mlx5_create_ipsec_obj+0xd6/0x200 mlx5e_accel_ipsec_fs_add_rule+0x31/0xf0 mlx5e_xfrm_add_state+0x426/0xc00 <snip> | ||||
| CVE-2024-36270 | 2 Linux, Redhat | 6 Linux Kernel, Enterprise Linux, Rhel Aus and 3 more | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: netfilter: tproxy: bail out if IP has been disabled on the device syzbot reports: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] [..] RIP: 0010:nf_tproxy_laddr4+0xb7/0x340 net/ipv4/netfilter/nf_tproxy_ipv4.c:62 Call Trace: nft_tproxy_eval_v4 net/netfilter/nft_tproxy.c:56 [inline] nft_tproxy_eval+0xa9a/0x1a00 net/netfilter/nft_tproxy.c:168 __in_dev_get_rcu() can return NULL, so check for this. | ||||
| CVE-2024-36023 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: Julia Lawall reported this null pointer dereference, this should fix it. | ||||
| CVE-2024-36014 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: drm/arm/malidp: fix a possible null pointer dereference In malidp_mw_connector_reset, new memory is allocated with kzalloc, but no check is performed. In order to prevent null pointer dereferencing, ensure that mw_state is checked before calling __drm_atomic_helper_connector_reset. | ||||
| CVE-2024-36010 | 1 Redhat | 2 Enterprise Linux, Rhel Eus | 2025-05-04 | 4.4 Medium |
| In the Linux kernel, the following vulnerability has been resolved: igb: Fix string truncation warnings in igb_set_fw_version Commit 1978d3ead82c ("intel: fix string truncation warnings") fixes '-Wformat-truncation=' warnings in igb_main.c by using kasprintf. drivers/net/ethernet/intel/igb/igb_main.c:3092:53: warning：‘%d’ directive output may be truncated writing between 1 and 5 bytes into a region of size between 1 and 13 [-Wformat-truncation=] 3092 | "%d.%d, 0x%08x, %d.%d.%d", | ^~ drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note：directive argument in the range [0, 65535] 3092 | "%d.%d, 0x%08x, %d.%d.%d", | ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note：directive argument in the range [0, 65535] drivers/net/ethernet/intel/igb/igb_main.c:3090:25: note：‘snprintf’ output between 23 and 43 bytes into a destination of size 32 kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Fix this warning by using a larger space for adapter->fw_version, and then fall back and continue to use snprintf. | ||||
| CVE-2024-36008 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: ipv4: check for NULL idev in ip_route_use_hint() syzbot was able to trigger a NULL deref in fib_validate_source() in an old tree [1]. It appears the bug exists in latest trees. All calls to __in_dev_get_rcu() must be checked for a NULL result. [1] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 2 PID: 3257 Comm: syz-executor.3 Not tainted 5.10.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:fib_validate_source+0xbf/0x15a0 net/ipv4/fib_frontend.c:425 Code: 18 f2 f2 f2 f2 42 c7 44 20 23 f3 f3 f3 f3 48 89 44 24 78 42 c6 44 20 27 f3 e8 5d 88 48 fc 4c 89 e8 48 c1 e8 03 48 89 44 24 18 <42> 80 3c 20 00 74 08 4c 89 ef e8 d2 15 98 fc 48 89 5c 24 10 41 bf RSP: 0018:ffffc900015fee40 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88800f7a4000 RCX: ffff88800f4f90c0 RDX: 0000000000000000 RSI: 0000000004001eac RDI: ffff8880160c64c0 RBP: ffffc900015ff060 R08: 0000000000000000 R09: ffff88800f7a4000 R10: 0000000000000002 R11: ffff88800f4f90c0 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88800f7a4000 FS: 00007f938acfe6c0(0000) GS:ffff888058c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f938acddd58 CR3: 000000001248e000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip_route_use_hint+0x410/0x9b0 net/ipv4/route.c:2231 ip_rcv_finish_core+0x2c4/0x1a30 net/ipv4/ip_input.c:327 ip_list_rcv_finish net/ipv4/ip_input.c:612 [inline] ip_sublist_rcv+0x3ed/0xe50 net/ipv4/ip_input.c:638 ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:673 __netif_receive_skb_list_ptype net/core/dev.c:5572 [inline] __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5620 __netif_receive_skb_list net/core/dev.c:5672 [inline] netif_receive_skb_list_internal+0x9f9/0xdc0 net/core/dev.c:5764 netif_receive_skb_list+0x55/0x3e0 net/core/dev.c:5816 xdp_recv_frames net/bpf/test_run.c:257 [inline] xdp_test_run_batch net/bpf/test_run.c:335 [inline] bpf_test_run_xdp_live+0x1818/0x1d00 net/bpf/test_run.c:363 bpf_prog_test_run_xdp+0x81f/0x1170 net/bpf/test_run.c:1376 bpf_prog_test_run+0x349/0x3c0 kernel/bpf/syscall.c:3736 __sys_bpf+0x45c/0x710 kernel/bpf/syscall.c:5115 __do_sys_bpf kernel/bpf/syscall.c:5201 [inline] __se_sys_bpf kernel/bpf/syscall.c:5199 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5199 | ||||
| CVE-2024-35985 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref. This turned out to be due to entity_eligible() returning falsely negative because of a s64 multiplcation overflow. Specifically, reweight_eevdf() computes the vlag without considering the limit placed upon vlag as update_entity_lag() does, and then the scaling multiplication (remember that weight is 20bit fixed point) can overflow. This then leads to the new vruntime being weird which then causes the above entity_eligible() to go side-ways and claim nothing is eligible. Thus limit the range of vlag accordingly. All this was quite rare, but fatal when it does happen. | ||||
| CVE-2024-35984 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: i2c: smbus: fix NULL function pointer dereference Baruch reported an OOPS when using the designware controller as target only. Target-only modes break the assumption of one transfer function always being available. Fix this by always checking the pointer in __i2c_transfer. [wsa: dropped the simplification in core-smbus to avoid theoretical regressions] | ||||
| CVE-2024-35977 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 4.7 Medium |
| In the Linux kernel, the following vulnerability has been resolved: platform/chrome: cros_ec_uart: properly fix race condition The cros_ec_uart_probe() function calls devm_serdev_device_open() before it calls serdev_device_set_client_ops(). This can trigger a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> ... ? ttyport_receive_buf A simplified version of crashing code is as follows: static inline size_t serdev_controller_receive_buf(struct serdev_controller *ctrl, const u8 *data, size_t count) { struct serdev_device *serdev = ctrl->serdev; if (!serdev || !serdev->ops->receive_buf) // CRASH! return 0; return serdev->ops->receive_buf(serdev, data, count); } It assumes that if SERPORT_ACTIVE is set and serdev exists, serdev->ops will also exist. This conflicts with the existing cros_ec_uart_probe() logic, as it first calls devm_serdev_device_open() (which sets SERPORT_ACTIVE), and only later sets serdev->ops via serdev_device_set_client_ops(). Commit 01f95d42b8f4 ("platform/chrome: cros_ec_uart: fix race condition") attempted to fix a similar race condition, but while doing so, made the window of error for this race condition to happen much wider. Attempt to fix the race condition again, making sure we fully setup before calling devm_serdev_device_open(). | ||||
| CVE-2024-35960 | 3 Debian, Linux, Redhat | 7 Debian Linux, Linux Kernel, Enterprise Linux and 4 more | 2025-05-04 | 9.1 Critical |
| In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Properly link new fs rules into the tree Previously, add_rule_fg would only add newly created rules from the handle into the tree when they had a refcount of 1. On the other hand, create_flow_handle tries hard to find and reference already existing identical rules instead of creating new ones. These two behaviors can result in a situation where create_flow_handle 1) creates a new rule and references it, then 2) in a subsequent step during the same handle creation references it again, resulting in a rule with a refcount of 2 that is not linked into the tree, will have a NULL parent and root and will result in a crash when the flow group is deleted because del_sw_hw_rule, invoked on rule deletion, assumes node->parent is != NULL. This happened in the wild, due to another bug related to incorrect handling of duplicate pkt_reformat ids, which lead to the code in create_flow_handle incorrectly referencing a just-added rule in the same flow handle, resulting in the problem described above. Full details are at [1]. This patch changes add_rule_fg to add new rules without parents into the tree, properly initializing them and avoiding the crash. This makes it more consistent with how rules are added to an FTE in create_flow_handle. | ||||
| CVE-2024-35946 | 2 Linux, Redhat | 3 Linux Kernel, Enterprise Linux, Rhel Eus | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: fix null pointer access when abort scan During cancel scan we might use vif that weren't scanning. Fix this by using the actual scanning vif. | ||||
| CVE-2024-35940 | 2 Debian, Linux | 2 Debian Linux, Linux Kernel | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: pstore/zone: Add a null pointer check to the psz_kmsg_read kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity. | ||||
| CVE-2024-35933 | 3 Debian, Linux, Redhat | 3 Debian Linux, Linux Kernel, Enterprise Linux | 2025-05-04 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btintel: Fix null ptr deref in btintel_read_version If hci_cmd_sync_complete() is triggered and skb is NULL, then hdev->req_skb is NULL, which will cause this issue. | ||||
| CVE-2024-35919 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 7 High |
| In the Linux kernel, the following vulnerability has been resolved: media: mediatek: vcodec: adding lock to protect encoder context list Add a lock for the ctx_list, to avoid accessing a NULL pointer within the 'vpu_enc_ipi_handler' function when the ctx_list has been deleted due to an unexpected behavior on the SCP IP block. | ||||
| CVE-2024-35916 | 1 Linux | 1 Linux Kernel | 2025-05-04 | 5.3 Medium |
| In the Linux kernel, the following vulnerability has been resolved: dma-buf: Fix NULL pointer dereference in sanitycheck() If due to a memory allocation failure mock_chain() returns NULL, it is passed to dma_fence_enable_sw_signaling() resulting in NULL pointer dereference there. Call dma_fence_enable_sw_signaling() only if mock_chain() succeeds. Found by Linux Verification Center (linuxtesting.org) with SVACE. | ||||