Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: tcp: prevent concurrent execution of tcp_sk_exit_batch Its possible that two threads call tcp_sk_exit_batch() concurrently, once from the cleanup_net workqueue, once from a task that failed to clone a new netns. In the latter case, error unwinding calls the exit handlers in reverse order for the 'failed' netns. tcp_sk_exit_batch() calls tcp_twsk_purge(). Problem is that since commit b099ce2602d8 ("net: Batch inet_twsk_purge"), this function picks up twsk in any dying netns, not just the one passed in via exit_batch list. This means that the error unwind of setup_net() can "steal" and destroy timewait sockets belonging to the exiting netns. This allows the netns exit worker to proceed to call WARN_ON_ONCE(!refcount_dec_and_test(&net->ipv4.tcp_death_row.tw_refcount)); without the expected 1 -> 0 transition, which then splats. At same time, error unwind path that is also running inet_twsk_purge() will splat as well: WARNING: .. at lib/refcount.c:31 refcount_warn_saturate+0x1ed/0x210 ... refcount_dec include/linux/refcount.h:351 [inline] inet_twsk_kill+0x758/0x9c0 net/ipv4/inet_timewait_sock.c:70 inet_twsk_deschedule_put net/ipv4/inet_timewait_sock.c:221 inet_twsk_purge+0x725/0x890 net/ipv4/inet_timewait_sock.c:304 tcp_sk_exit_batch+0x1c/0x170 net/ipv4/tcp_ipv4.c:3522 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178 setup_net+0x714/0xb40 net/core/net_namespace.c:375 copy_net_ns+0x2f0/0x670 net/core/net_namespace.c:508 create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110 ... because refcount_dec() of tw_refcount unexpectedly dropped to 0. This doesn't seem like an actual bug (no tw sockets got lost and I don't see a use-after-free) but as erroneous trigger of debug check. Add a mutex to force strict ordering: the task that calls tcp_twsk_purge() blocks other task from doing final _dec_and_test before mutex-owner has removed all tw sockets of dying netns.Show less

In the Linux kernel, the following vulnerability has been resolved: bonding: fix xfrm real_dev null pointer dereference We shouldn't set real_dev to NULL because packets can be in transit and xfrm might call xdo_dev_offload_ok() in parallel. All callbacks assume real_dev is set. Example trace: kernel: BUG: unable to handle page fault for address: 0000000000001030 kernel: bond0: (slave eni0np1): making interface the new active one kernel: #PF: supervisor write access in kernel mode kernel: #PF: error_code(0x0002) - not-present page kernel: PGD 0 P4D 0 kernel: Oops: 0002 [#1] PREEMPT SMP kernel: CPU: 4 PID: 2237 Comm: ping Not tainted 6.7.7+ #12 kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014 kernel: RIP: 0010:nsim_ipsec_offload_ok+0xc/0x20 [netdevsim] kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: Code: e0 0f 0b 48 83 7f 38 00 74 de 0f 0b 48 8b 47 08 48 8b 37 48 8b 78 40 e9 b2 e5 9a d7 66 90 0f 1f 44 00 00 48 8b 86 80 02 00 00 <83> 80 30 10 00 00 01 b8 01 00 00 00 c3 0f 1f 80 00 00 00 00 0f 1f kernel: bond0: (slave eni0np1): making interface the new active one kernel: RSP: 0018:ffffabde81553b98 EFLAGS: 00010246 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: kernel: RAX: 0000000000000000 RBX: ffff9eb404e74900 RCX: ffff9eb403d97c60 kernel: RDX: ffffffffc090de10 RSI: ffff9eb404e74900 RDI: ffff9eb3c5de9e00 kernel: RBP: ffff9eb3c0a42000 R08: 0000000000000010 R09: 0000000000000014 kernel: R10: 7974203030303030 R11: 3030303030303030 R12: 0000000000000000 kernel: R13: ffff9eb3c5de9e00 R14: ffffabde81553cc8 R15: ffff9eb404c53000 kernel: FS: 00007f2a77a3ad00(0000) GS:ffff9eb43bd00000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000001030 CR3: 00000001122ab000 CR4: 0000000000350ef0 kernel: bond0: (slave eni0np1): making interface the new active one kernel: Call Trace: kernel: <TASK> kernel: ? __die+0x1f/0x60 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ? page_fault_oops+0x142/0x4c0 kernel: ? do_user_addr_fault+0x65/0x670 kernel: ? kvm_read_and_reset_apf_flags+0x3b/0x50 kernel: bond0: (slave eni0np1): making interface the new active one kernel: ? exc_page_fault+0x7b/0x180 kernel: ? asm_exc_page_fault+0x22/0x30 kernel: ? nsim_bpf_uninit+0x50/0x50 [netdevsim] kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ? nsim_ipsec_offload_ok+0xc/0x20 [netdevsim] kernel: bond0: (slave eni0np1): making interface the new active one kernel: bond_ipsec_offload_ok+0x7b/0x90 [bonding] kernel: xfrm_output+0x61/0x3b0 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ip_push_pending_frames+0x56/0x80Show less

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mv88e6xxx: Fix out-of-bound access If an ATU violation was caused by a CPU Load operation, the SPID could be larger than DSA_MAX_PORTS (the size of mv88e6xxx_chip.ports[] array).Show less

In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent UAF in ip6_send_skb() syzbot reported an UAF in ip6_send_skb() [1] After ip6_local_out() has returned, we no longer can safely dereference rt, unless we hold rcu_read_lock(). A similar issue has been fixed in commit a688caa34beb ("ipv6: take rcu lock in rawv6_send_hdrinc()") Another potential issue in ip6_finish_output2() is handled in a separate patch. [1] BUG: KASAN: slab-use-after-free in ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 Read of size 8 at addr ffff88806dde4858 by task syz.1.380/6530 CPU: 1 UID: 0 PID: 6530 Comm: syz.1.380 Not tainted 6.11.0-rc3-syzkaller-00306-gdf6cbc62cc9b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588 rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 do_iter_readv_writev+0x60a/0x890 vfs_writev+0x37c/0xbb0 fs/read_write.c:971 do_writev+0x1b1/0x350 fs/read_write.c:1018 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f936bf79e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f936cd7f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f936c115f80 RCX: 00007f936bf79e79 RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 00007f936bfe7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f936c115f80 R15: 00007fff2860a7a8 </TASK> Allocated by task 6530: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 dst_alloc+0x12b/0x190 net/core/dst.c:89 ip6_blackhole_route+0x59/0x340 net/ipv6/route.c:2670 make_blackhole net/xfrm/xfrm_policy.c:3120 [inline] xfrm_lookup_route+0xd1/0x1c0 net/xfrm/xfrm_policy.c:3313 ip6_dst_lookup_flow+0x13e/0x180 net/ipv6/ip6_output.c:1257 rawv6_sendmsg+0x1283/0x23c0 net/ipv6/raw.c:898 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 45: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 dst_destroy+0x2ac/0x460 net/core/dst.c:124 rcu_do_batch kernel/rcu/tree.c:2569 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree. ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix possible UAF in ip6_finish_output2() If skb_expand_head() returns NULL, skb has been freed and associated dst/idev could also have been freed. We need to hold rcu_read_lock() to make sure the dst and associated idev are alive.Show less

In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent possible UAF in ip6_xmit() If skb_expand_head() returns NULL, skb has been freed and the associated dst/idev could also have been freed. We must use rcu_read_lock() to prevent a possible UAF.Show less

In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix double DMA unmapping for XDP_REDIRECT Remove the dma_unmap_page_attrs() call in the driver's XDP_REDIRECT code path. This should have been removed when we let the page pool handle the DMA mapping. This bug causes the warning: WARNING: CPU: 7 PID: 59 at drivers/iommu/dma-iommu.c:1198 iommu_dma_unmap_page+0xd5/0x100 CPU: 7 PID: 59 Comm: ksoftirqd/7 Tainted: G W 6.8.0-1010-gcp #11-Ubuntu Hardware name: Dell Inc. PowerEdge R7525/0PYVT1, BIOS 2.15.2 04/02/2024 RIP: 0010:iommu_dma_unmap_page+0xd5/0x100 Code: 89 ee 48 89 df e8 cb f2 69 ff 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d 31 c0 31 d2 31 c9 31 f6 31 ff 45 31 c0 e9 ab 17 71 00 <0f> 0b 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d 31 c0 31 d2 31 c9 RSP: 0018:ffffab1fc0597a48 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff99ff838280c8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffab1fc0597a78 R08: 0000000000000002 R09: ffffab1fc0597c1c R10: ffffab1fc0597cd3 R11: ffff99ffe375acd8 R12: 00000000e65b9000 R13: 0000000000000050 R14: 0000000000001000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff9a06efb80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000565c34c37210 CR3: 00000005c7e3e000 CR4: 0000000000350ef0 ? show_regs+0x6d/0x80 ? __warn+0x89/0x150 ? iommu_dma_unmap_page+0xd5/0x100 ? report_bug+0x16a/0x190 ? handle_bug+0x51/0xa0 ? exc_invalid_op+0x18/0x80 ? iommu_dma_unmap_page+0xd5/0x100 ? iommu_dma_unmap_page+0x35/0x100 dma_unmap_page_attrs+0x55/0x220 ? bpf_prog_4d7e87c0d30db711_xdp_dispatcher+0x64/0x9f bnxt_rx_xdp+0x237/0x520 [bnxt_en] bnxt_rx_pkt+0x640/0xdd0 [bnxt_en] __bnxt_poll_work+0x1a1/0x3d0 [bnxt_en] bnxt_poll+0xaa/0x1e0 [bnxt_en] __napi_poll+0x33/0x1e0 net_rx_action+0x18a/0x2f0Show less

In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: validate vlan header Ensure there is sufficient room to access the protocol field of the VLAN header, validate it once before the flowtable lookup. ===================================================== BUG: KMSAN: uninit-value in nf_flow_offload_inet_hook+0x45a/0x5f0 net/netfilter/nf_flow_table_inet.c:32 nf_flow_offload_inet_hook+0x45a/0x5f0 net/netfilter/nf_flow_table_inet.c:32 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline] nf_ingress net/core/dev.c:5440 [inline]Show less

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: cleanup FB if dpu_format_populate_layout fails If the dpu_format_populate_layout() fails, then FB is prepared, but not cleaned up. This ends up leaking the pin_count on the GEM object and causes a splat during DRM file closure: msm_obj->pin_count WARNING: CPU: 2 PID: 569 at drivers/gpu/drm/msm/msm_gem.c:121 update_lru_locked+0xc4/0xcc [...] Call trace: update_lru_locked+0xc4/0xcc put_pages+0xac/0x100 msm_gem_free_object+0x138/0x180 drm_gem_object_free+0x1c/0x30 drm_gem_object_handle_put_unlocked+0x108/0x10c drm_gem_object_release_handle+0x58/0x70 idr_for_each+0x68/0xec drm_gem_release+0x28/0x40 drm_file_free+0x174/0x234 drm_release+0xb0/0x160 __fput+0xc0/0x2c8 __fput_sync+0x50/0x5c __arm64_sys_close+0x38/0x7c invoke_syscall+0x48/0x118 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x4c/0x120 el0t_64_sync_handler+0x100/0x12c el0t_64_sync+0x190/0x194 irq event stamp: 129818 hardirqs last enabled at (129817): [<ffffa5f6d953fcc0>] console_unlock+0x118/0x124 hardirqs last disabled at (129818): [<ffffa5f6da7dcf04>] el1_dbg+0x24/0x8c softirqs last enabled at (129808): [<ffffa5f6d94afc18>] handle_softirqs+0x4c8/0x4e8 softirqs last disabled at (129785): [<ffffa5f6d94105e4>] __do_softirq+0x14/0x20 Patchwork: https://patchwork.freedesktop.org/patch/600714/Show less

In the Linux kernel, the following vulnerability has been resolved: workqueue: Fix UBSAN 'subtraction overflow' error in shift_and_mask() UBSAN reports the following 'subtraction overflow' error when booting in a virtual machine on Android: | Internal error: UBSAN: integer subtraction overflow: 00000000f2005515 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.10.0-00006-g3cbe9e5abd46-dirty #4 | Hardware name: linux,dummy-virt (DT) | pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : cancel_delayed_work+0x34/0x44 | lr : cancel_delayed_work+0x2c/0x44 | sp : ffff80008002ba60 | x29: ffff80008002ba60 x28: 0000000000000000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: 0000000000000000 x22: 0000000000000000 x21: ffff1f65014cd3c0 | x20: ffffc0e84c9d0da0 x19: ffffc0e84cab3558 x18: ffff800080009058 | x17: 00000000247ee1f8 x16: 00000000247ee1f8 x15: 00000000bdcb279d | x14: 0000000000000001 x13: 0000000000000075 x12: 00000a0000000000 | x11: ffff1f6501499018 x10: 00984901651fffff x9 : ffff5e7cc35af000 | x8 : 0000000000000001 x7 : 3d4d455453595342 x6 : 000000004e514553 | x5 : ffff1f6501499265 x4 : ffff1f650ff60b10 x3 : 0000000000000620 | x2 : ffff80008002ba78 x1 : 0000000000000000 x0 : 0000000000000000 | Call trace: | cancel_delayed_work+0x34/0x44 | deferred_probe_extend_timeout+0x20/0x70 | driver_register+0xa8/0x110 | __platform_driver_register+0x28/0x3c | syscon_init+0x24/0x38 | do_one_initcall+0xe4/0x338 | do_initcall_level+0xac/0x178 | do_initcalls+0x5c/0xa0 | do_basic_setup+0x20/0x30 | kernel_init_freeable+0x8c/0xf8 | kernel_init+0x28/0x1b4 | ret_from_fork+0x10/0x20 | Code: f9000fbf 97fffa2f 39400268 37100048 (d42aa2a0) | ---[ end trace 0000000000000000 ]--- | Kernel panic - not syncing: UBSAN: integer subtraction overflow: Fatal exception This is due to shift_and_mask() using a signed immediate to construct the mask and being called with a shift of 31 (WORK_OFFQ_POOL_SHIFT) so that it ends up decrementing from INT_MIN. Use an unsigned constant '1U' to generate the mask in shift_and_mask().Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix opregion leak Being part o the display, ideally the setup and cleanup would be done by display itself. However this is a bigger refactor that needs to be done on both i915 and xe. For now, just fix the leak: unreferenced object 0xffff8881a0300008 (size 192): comm "modprobe", pid 4354, jiffies 4295647021 hex dump (first 32 bytes): 00 00 87 27 81 88 ff ff 18 80 9b 00 00 c9 ff ff ...'............ 18 81 9b 00 00 c9 ff ff 00 00 00 00 00 00 00 00 ................ backtrace (crc 99260e31): [<ffffffff823ce65b>] kmemleak_alloc+0x4b/0x80 [<ffffffff81493be2>] kmalloc_trace_noprof+0x312/0x3d0 [<ffffffffa1345679>] intel_opregion_setup+0x89/0x700 [xe] [<ffffffffa125bfaf>] xe_display_init_noirq+0x2f/0x90 [xe] [<ffffffffa1199ec3>] xe_device_probe+0x7a3/0xbf0 [xe] [<ffffffffa11f3713>] xe_pci_probe+0x333/0x5b0 [xe] [<ffffffff81af6be8>] local_pci_probe+0x48/0xb0 [<ffffffff81af8778>] pci_device_probe+0xc8/0x280 [<ffffffff81d09048>] really_probe+0xf8/0x390 [<ffffffff81d0937a>] __driver_probe_device+0x8a/0x170 [<ffffffff81d09503>] driver_probe_device+0x23/0xb0 [<ffffffff81d097b7>] __driver_attach+0xc7/0x190 [<ffffffff81d0628d>] bus_for_each_dev+0x7d/0xd0 [<ffffffff81d0851e>] driver_attach+0x1e/0x30 [<ffffffff81d07ac7>] bus_add_driver+0x117/0x250 (cherry picked from commit 6f4e43a2f771b737d991142ec4f6d4b7ff31fbb4)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix missing workqueue destroy in xe_gt_pagefault On driver reload we never free up the memory for the pagefault and access counter workqueues. Add those destroy calls here. (cherry picked from commit 7586fc52b14e0b8edd0d1f8a434e0de2078b7b2b)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Free job before xe_exec_queue_put Free job depends on job->vm being valid, the last xe_exec_queue_put can destroy the VM. Prevent UAF by freeing job before xe_exec_queue_put. (cherry picked from commit 32a42c93b74c8ca6d0915ea3eba21bceff53042f)Show less

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Validate TA binary size Add TA binary size validation to avoid OOB write. (cherry picked from commit c0a04e3570d72aaf090962156ad085e37c62e442)Show less

In the Linux kernel, the following vulnerability has been resolved: ata: pata_macio: Fix DMA table overflow Kolbjørn and Jonáš reported that their 32-bit PowerMacs were crashing in pata-macio since commit 09fe2bfa6b83 ("ata: pata_macio: Fix max_segment_size with PAGE_SIZE == 64K"). For example: kernel BUG at drivers/ata/pata_macio.c:544! Oops: Exception in kernel mode, sig: 5 [#1] BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 DEBUG_PAGEALLOC PowerMac ... NIP pata_macio_qc_prep+0xf4/0x190 LR pata_macio_qc_prep+0xfc/0x190 Call Trace: 0xc1421660 (unreliable) ata_qc_issue+0x14c/0x2d4 __ata_scsi_queuecmd+0x200/0x53c ata_scsi_queuecmd+0x50/0xe0 scsi_queue_rq+0x788/0xb1c __blk_mq_issue_directly+0x58/0xf4 blk_mq_plug_issue_direct+0x8c/0x1b4 blk_mq_flush_plug_list.part.0+0x584/0x5e0 __blk_flush_plug+0xf8/0x194 __submit_bio+0x1b8/0x2e0 submit_bio_noacct_nocheck+0x230/0x304 btrfs_work_helper+0x200/0x338 process_one_work+0x1a8/0x338 worker_thread+0x364/0x4c0 kthread+0x100/0x104 start_kernel_thread+0x10/0x14 That commit increased max_segment_size to 64KB, with the justification that the SCSI core was already using that size when PAGE_SIZE == 64KB, and that there was existing logic to split over-sized requests. However with a sufficiently large request, the splitting logic causes each sg to be split into two commands in the DMA table, leading to overflow of the DMA table, triggering the BUG_ON(). With default settings the bug doesn't trigger, because the request size is limited by max_sectors_kb == 1280, however max_sectors_kb can be increased, and apparently some distros do that by default using udev rules. Fix the bug for 4KB kernels by reverting to the old max_segment_size. For 64KB kernels the sg_tablesize needs to be halved, to allow for the possibility that each sg will be split into two.Show less

In the Linux kernel, the following vulnerability has been resolved: cgroup/cpuset: fix panic caused by partcmd_update We find a bug as below: BUG: unable to handle page fault for address: 00000003 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 3 PID: 358 Comm: bash Tainted: G W I 6.6.0-10893-g60d6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/4 RIP: 0010:partition_sched_domains_locked+0x483/0x600 Code: 01 48 85 d2 74 0d 48 83 05 29 3f f8 03 01 f3 48 0f bc c2 89 c0 48 9 RSP: 0018:ffffc90000fdbc58 EFLAGS: 00000202 RAX: 0000000100000003 RBX: ffff888100b3dfa0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000002fe80 RBP: ffff888100b3dfb0 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc90000fdbcb0 R11: 0000000000000004 R12: 0000000000000002 R13: ffff888100a92b48 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f44a5425740(0000) GS:ffff888237d80000(0000) knlGS:0000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100030973 CR3: 000000010722c000 CR4: 00000000000006e0 Call Trace: <TASK> ? show_regs+0x8c/0xa0 ? __die_body+0x23/0xa0 ? __die+0x3a/0x50 ? page_fault_oops+0x1d2/0x5c0 ? partition_sched_domains_locked+0x483/0x600 ? search_module_extables+0x2a/0xb0 ? search_exception_tables+0x67/0x90 ? kernelmode_fixup_or_oops+0x144/0x1b0 ? __bad_area_nosemaphore+0x211/0x360 ? up_read+0x3b/0x50 ? bad_area_nosemaphore+0x1a/0x30 ? exc_page_fault+0x890/0xd90 ? __lock_acquire.constprop.0+0x24f/0x8d0 ? __lock_acquire.constprop.0+0x24f/0x8d0 ? asm_exc_page_fault+0x26/0x30 ? partition_sched_domains_locked+0x483/0x600 ? partition_sched_domains_locked+0xf0/0x600 rebuild_sched_domains_locked+0x806/0xdc0 update_partition_sd_lb+0x118/0x130 cpuset_write_resmask+0xffc/0x1420 cgroup_file_write+0xb2/0x290 kernfs_fop_write_iter+0x194/0x290 new_sync_write+0xeb/0x160 vfs_write+0x16f/0x1d0 ksys_write+0x81/0x180 __x64_sys_write+0x21/0x30 x64_sys_call+0x2f25/0x4630 do_syscall_64+0x44/0xb0 entry_SYSCALL_64_after_hwframe+0x78/0xe2 RIP: 0033:0x7f44a553c887 It can be reproduced with cammands: cd /sys/fs/cgroup/ mkdir test cd test/ echo +cpuset > ../cgroup.subtree_control echo root > cpuset.cpus.partition cat /sys/fs/cgroup/cpuset.cpus.effective 0-3 echo 0-3 > cpuset.cpus // taking away all cpus from root This issue is caused by the incorrect rebuilding of scheduling domains. In this scenario, test/cpuset.cpus.partition should be an invalid root and should not trigger the rebuilding of scheduling domains. When calling update_parent_effective_cpumask with partcmd_update, if newmask is not null, it should recheck newmask whether there are cpus is available for parect/cs that has tasks.Show less

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: avoid possible UaF when selecting endp select_local_address() and select_signal_address() both select an endpoint entry from the list inside an RCU protected section, but return a reference to it, to be read later on. If the entry is dereferenced after the RCU unlock, reading info could cause a Use-after-Free. A simple solution is to copy the required info while inside the RCU protected section to avoid any risk of UaF later. The address ID might need to be modified later to handle the ID0 case later, so a copy seems OK to deal with.Show less

In the Linux kernel, the following vulnerability has been resolved: mm, slub: do not call do_slab_free for kfence object In 782f8906f805 the freeing of kfence objects was moved from deep inside do_slab_free to the wrapper functions outside. This is a nice change, but unfortunately it missed one spot in __kmem_cache_free_bulk. This results in a crash like this: BUG skbuff_head_cache (Tainted: G S B E ): Padding overwritten. 0xffff88907fea0f00-0xffff88907fea0fff @offset=3840 slab_err (mm/slub.c:1129) free_to_partial_list (mm/slub.c:? mm/slub.c:4036) slab_pad_check (mm/slub.c:864 mm/slub.c:1290) check_slab (mm/slub.c:?) free_to_partial_list (mm/slub.c:3171 mm/slub.c:4036) kmem_cache_alloc_bulk (mm/slub.c:? mm/slub.c:4495 mm/slub.c:4586 mm/slub.c:4635) napi_build_skb (net/core/skbuff.c:348 net/core/skbuff.c:527 net/core/skbuff.c:549) All the other callers to do_slab_free appear to be ok. Add a kfence_free check in __kmem_cache_free_bulk to avoid the crash.Show less

In the Linux kernel, the following vulnerability has been resolved: net: dsa: bcm_sf2: Fix a possible memory leak in bcm_sf2_mdio_register() bcm_sf2_mdio_register() calls of_phy_find_device() and then phy_device_remove() in a loop to remove existing PHY devices. of_phy_find_device() eventually calls bus_find_device(), which calls get_device() on the returned struct device * to increment the refcount. The current implementation does not decrement the refcount, which causes memory leak. This commit adds the missing phy_device_free() call to decrement the refcount via put_device() to balance the refcount.Show less