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15641 CVE
| CVE | Vendors | Products | Updated | CVSS v3.1 |
|---|---|---|---|---|
| CVE-2024-36929 | 3 Debian, Linux, Redhat | 7 Debian Linux, Linux Kernel, Enterprise Linux and 4 more | 2026-01-22 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: net: core: reject skb_copy(_expand) for fraglist GSO skbs SKB_GSO_FRAGLIST skbs must not be linearized, otherwise they become invalid. Return NULL if such an skb is passed to skb_copy or skb_copy_expand, in order to prevent a crash on a potential later call to skb_gso_segment. | ||||
| CVE-2024-36919 | 3 Debian, Linux, Redhat | 3 Debian Linux, Linux Kernel, Enterprise Linux | 2026-01-22 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: scsi: bnx2fc: Remove spin_lock_bh while releasing resources after upload The session resources are used by FW and driver when session is offloaded, once session is uploaded these resources are not used. The lock is not required as these fields won't be used any longer. The offload and upload calls are sequential, hence lock is not required. This will suppress following BUG_ON(): [ 449.843143] ------------[ cut here ]------------ [ 449.848302] kernel BUG at mm/vmalloc.c:2727! [ 449.853072] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 449.858712] CPU: 5 PID: 1996 Comm: kworker/u24:2 Not tainted 5.14.0-118.el9.x86_64 #1 Rebooting. [ 449.867454] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.3.4 11/08/2016 [ 449.876966] Workqueue: fc_rport_eq fc_rport_work [libfc] [ 449.882910] RIP: 0010:vunmap+0x2e/0x30 [ 449.887098] Code: 00 65 8b 05 14 a2 f0 4a a9 00 ff ff 00 75 1b 55 48 89 fd e8 34 36 79 00 48 85 ed 74 0b 48 89 ef 31 f6 5d e9 14 fc ff ff 5d c3 <0f> 0b 0f 1f 44 00 00 41 57 41 56 49 89 ce 41 55 49 89 fd 41 54 41 [ 449.908054] RSP: 0018:ffffb83d878b3d68 EFLAGS: 00010206 [ 449.913887] RAX: 0000000080000201 RBX: ffff8f4355133550 RCX: 000000000d400005 [ 449.921843] RDX: 0000000000000001 RSI: 0000000000001000 RDI: ffffb83da53f5000 [ 449.929808] RBP: ffff8f4ac6675800 R08: ffffb83d878b3d30 R09: 00000000000efbdf [ 449.937774] R10: 0000000000000003 R11: ffff8f434573e000 R12: 0000000000001000 [ 449.945736] R13: 0000000000001000 R14: ffffb83da53f5000 R15: ffff8f43d4ea3ae0 [ 449.953701] FS: 0000000000000000(0000) GS:ffff8f529fc80000(0000) knlGS:0000000000000000 [ 449.962732] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 449.969138] CR2: 00007f8cf993e150 CR3: 0000000efbe10003 CR4: 00000000003706e0 [ 449.977102] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 449.985065] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 449.993028] Call Trace: [ 449.995756] __iommu_dma_free+0x96/0x100 [ 450.000139] bnx2fc_free_session_resc+0x67/0x240 [bnx2fc] [ 450.006171] bnx2fc_upload_session+0xce/0x100 [bnx2fc] [ 450.011910] bnx2fc_rport_event_handler+0x9f/0x240 [bnx2fc] [ 450.018136] fc_rport_work+0x103/0x5b0 [libfc] [ 450.023103] process_one_work+0x1e8/0x3c0 [ 450.027581] worker_thread+0x50/0x3b0 [ 450.031669] ? rescuer_thread+0x370/0x370 [ 450.036143] kthread+0x149/0x170 [ 450.039744] ? set_kthread_struct+0x40/0x40 [ 450.044411] ret_from_fork+0x22/0x30 [ 450.048404] Modules linked in: vfat msdos fat xfs nfs_layout_nfsv41_files rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver dm_service_time qedf qed crc8 bnx2fc libfcoe libfc scsi_transport_fc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp dcdbas rapl intel_cstate intel_uncore mei_me pcspkr mei ipmi_ssif lpc_ich ipmi_si fuse zram ext4 mbcache jbd2 loop nfsv3 nfs_acl nfs lockd grace fscache netfs irdma ice sd_mod t10_pi sg ib_uverbs ib_core 8021q garp mrp stp llc mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt mxm_wmi fb_sys_fops cec crct10dif_pclmul ahci crc32_pclmul bnx2x drm ghash_clmulni_intel libahci rfkill i40e libata megaraid_sas mdio wmi sunrpc lrw dm_crypt dm_round_robin dm_multipath dm_snapshot dm_bufio dm_mirror dm_region_hash dm_log dm_zero dm_mod linear raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx raid6_pq libcrc32c crc32c_intel raid1 raid0 iscsi_ibft squashfs be2iscsi bnx2i cnic uio cxgb4i cxgb4 tls [ 450.048497] libcxgbi libcxgb qla4xxx iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi edd ipmi_devintf ipmi_msghandler [ 450.159753] ---[ end trace 712de2c57c64abc8 ]--- | ||||
| CVE-2023-41175 | 3 Fedoraproject, Libtiff, Redhat | 3 Fedora, Libtiff, Enterprise Linux | 2026-01-22 | 6.5 Medium |
| A vulnerability was found in libtiff due to multiple potential integer overflows in raw2tiff.c. This flaw allows remote attackers to cause a denial of service or possibly execute an arbitrary code via a crafted tiff image, which triggers a heap-based buffer overflow. | ||||
| CVE-2023-40745 | 4 Fedoraproject, Libtiff, Netapp and 1 more | 4 Fedora, Libtiff, Active Iq Unified Manager and 1 more | 2026-01-22 | 6.5 Medium |
| LibTIFF is vulnerable to an integer overflow. This flaw allows remote attackers to cause a denial of service (application crash) or possibly execute an arbitrary code via a crafted tiff image, which triggers a heap-based buffer overflow. | ||||
| CVE-2023-6277 | 3 Fedoraproject, Libtiff, Redhat | 3 Fedora, Libtiff, Enterprise Linux | 2026-01-22 | 6.5 Medium |
| An out-of-memory flaw was found in libtiff. Passing a crafted tiff file to TIFFOpen() API may allow a remote attacker to cause a denial of service via a craft input with size smaller than 379 KB. | ||||
| CVE-2023-3576 | 3 Fedoraproject, Libtiff, Redhat | 3 Fedora, Libtiff, Enterprise Linux | 2026-01-22 | 5.5 Medium |
| A memory leak flaw was found in Libtiff's tiffcrop utility. This issue occurs when tiffcrop operates on a TIFF image file, allowing an attacker to pass a crafted TIFF image file to tiffcrop utility, which causes this memory leak issue, resulting an application crash, eventually leading to a denial of service. | ||||
| CVE-2023-1393 | 3 Fedoraproject, Redhat, X.org | 7 Fedora, Enterprise Linux, Rhel Aus and 4 more | 2026-01-22 | 7.8 High |
| A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later. | ||||
| CVE-2025-8114 | 2 Libssh, Redhat | 3 Libssh, Enterprise Linux, Openshift | 2026-01-22 | 4.7 Medium |
| A flaw was found in libssh, a library that implements the SSH protocol. When calculating the session ID during the key exchange (KEX) process, an allocation failure in cryptographic functions may lead to a NULL pointer dereference. This issue can cause the client or server to crash. | ||||
| CVE-2023-47038 | 3 Fedoraproject, Perl, Redhat | 5 Fedora, Perl, Enterprise Linux and 2 more | 2026-01-22 | 7 High |
| A vulnerability was found in perl 5.30.0 through 5.38.0. This issue occurs when a crafted regular expression is compiled by perl, which can allow an attacker controlled byte buffer overflow in a heap allocated buffer. | ||||
| CVE-2022-49465 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2026-01-21 | 7.8 High |
| In the Linux kernel, the following vulnerability has been resolved: blk-throttle: Set BIO_THROTTLED when bio has been throttled 1.In current process, all bio will set the BIO_THROTTLED flag after __blk_throtl_bio(). 2.If bio needs to be throttled, it will start the timer and stop submit bio directly. Bio will submit in blk_throtl_dispatch_work_fn() when the timer expires.But in the current process, if bio is throttled. The BIO_THROTTLED will be set to bio after timer start. If the bio has been completed, it may cause use-after-free blow. BUG: KASAN: use-after-free in blk_throtl_bio+0x12f0/0x2c70 Read of size 2 at addr ffff88801b8902d4 by task fio/26380 dump_stack+0x9b/0xce print_address_description.constprop.6+0x3e/0x60 kasan_report.cold.9+0x22/0x3a blk_throtl_bio+0x12f0/0x2c70 submit_bio_checks+0x701/0x1550 submit_bio_noacct+0x83/0xc80 submit_bio+0xa7/0x330 mpage_readahead+0x380/0x500 read_pages+0x1c1/0xbf0 page_cache_ra_unbounded+0x471/0x6f0 do_page_cache_ra+0xda/0x110 ondemand_readahead+0x442/0xae0 page_cache_async_ra+0x210/0x300 generic_file_buffered_read+0x4d9/0x2130 generic_file_read_iter+0x315/0x490 blkdev_read_iter+0x113/0x1b0 aio_read+0x2ad/0x450 io_submit_one+0xc8e/0x1d60 __se_sys_io_submit+0x125/0x350 do_syscall_64+0x2d/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Allocated by task 26380: kasan_save_stack+0x19/0x40 __kasan_kmalloc.constprop.2+0xc1/0xd0 kmem_cache_alloc+0x146/0x440 mempool_alloc+0x125/0x2f0 bio_alloc_bioset+0x353/0x590 mpage_alloc+0x3b/0x240 do_mpage_readpage+0xddf/0x1ef0 mpage_readahead+0x264/0x500 read_pages+0x1c1/0xbf0 page_cache_ra_unbounded+0x471/0x6f0 do_page_cache_ra+0xda/0x110 ondemand_readahead+0x442/0xae0 page_cache_async_ra+0x210/0x300 generic_file_buffered_read+0x4d9/0x2130 generic_file_read_iter+0x315/0x490 blkdev_read_iter+0x113/0x1b0 aio_read+0x2ad/0x450 io_submit_one+0xc8e/0x1d60 __se_sys_io_submit+0x125/0x350 do_syscall_64+0x2d/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 0: kasan_save_stack+0x19/0x40 kasan_set_track+0x1c/0x30 kasan_set_free_info+0x1b/0x30 __kasan_slab_free+0x111/0x160 kmem_cache_free+0x94/0x460 mempool_free+0xd6/0x320 bio_free+0xe0/0x130 bio_put+0xab/0xe0 bio_endio+0x3a6/0x5d0 blk_update_request+0x590/0x1370 scsi_end_request+0x7d/0x400 scsi_io_completion+0x1aa/0xe50 scsi_softirq_done+0x11b/0x240 blk_mq_complete_request+0xd4/0x120 scsi_mq_done+0xf0/0x200 virtscsi_vq_done+0xbc/0x150 vring_interrupt+0x179/0x390 __handle_irq_event_percpu+0xf7/0x490 handle_irq_event_percpu+0x7b/0x160 handle_irq_event+0xcc/0x170 handle_edge_irq+0x215/0xb20 common_interrupt+0x60/0x120 asm_common_interrupt+0x1e/0x40 Fix this by move BIO_THROTTLED set into the queue_lock. | ||||
| CVE-2025-4478 | 2 Freerdp, Redhat | 2 Freerdp, Enterprise Linux | 2026-01-21 | 6.5 Medium |
| A flaw was found in the FreeRDP used by Anaconda's remote install feature, where a crafted RDP packet could trigger a segmentation fault. This issue causes the service to crash and remain defunct, resulting in a denial of service. It occurs pre-boot and is likely due to a NULL pointer dereference. Rebooting is required to recover the system. | ||||
| CVE-2020-10188 | 7 Arista, Debian, Fedoraproject and 4 more | 10 Eos, Debian Linux, Fedora and 7 more | 2026-01-21 | 9.8 Critical |
| utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions. | ||||
| CVE-2024-49968 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2026-01-19 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: ext4: filesystems without casefold feature cannot be mounted with siphash When mounting the ext4 filesystem, if the default hash version is set to DX_HASH_SIPHASH but the casefold feature is not set, exit the mounting. | ||||
| CVE-2024-40928 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2026-01-19 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: net: ethtool: fix the error condition in ethtool_get_phy_stats_ethtool() Clang static checker (scan-build) warning: net/ethtool/ioctl.c:line 2233, column 2 Called function pointer is null (null dereference). Return '-EOPNOTSUPP' when 'ops->get_ethtool_phy_stats' is NULL to fix this typo error. | ||||
| CVE-2024-36927 | 2 Linux, Redhat | 3 Linux Kernel, Enterprise Linux, Rhel Eus | 2026-01-19 | 4.7 Medium |
| In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix uninit-value access in __ip_make_skb() KMSAN reported uninit-value access in __ip_make_skb() [1]. __ip_make_skb() tests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a race condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL while __ip_make_skb() is running, the function will access icmphdr in the skb even if it is not included. This causes the issue reported by KMSAN. Check FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL on the socket. Also, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These are union in struct flowi4 and are implicitly initialized by flowi4_init_output(), but we should not rely on specific union layout. Initialize these explicitly in raw_sendmsg(). [1] BUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 ip_finish_skb include/net/ip.h:243 [inline] ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit was created at: slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1318 [inline] __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365 raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014 | ||||
| CVE-2024-36903 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2026-01-19 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: ipv6: Fix potential uninit-value access in __ip6_make_skb() As it was done in commit fc1092f51567 ("ipv4: Fix uninit-value access in __ip_make_skb()") for IPv4, check FLOWI_FLAG_KNOWN_NH on fl6->flowi6_flags instead of testing HDRINCL on the socket to avoid a race condition which causes uninit-value access. | ||||
| CVE-2024-39500 | 2 Linux, Redhat | 2 Linux Kernel, Enterprise Linux | 2026-01-19 | 4.7 Medium |
| In the Linux kernel, the following vulnerability has been resolved: sock_map: avoid race between sock_map_close and sk_psock_put sk_psock_get will return NULL if the refcount of psock has gone to 0, which will happen when the last call of sk_psock_put is done. However, sk_psock_drop may not have finished yet, so the close callback will still point to sock_map_close despite psock being NULL. This can be reproduced with a thread deleting an element from the sock map, while the second one creates a socket, adds it to the map and closes it. That will trigger the WARN_ON_ONCE: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 7220 at net/core/sock_map.c:1701 sock_map_close+0x2a2/0x2d0 net/core/sock_map.c:1701 Modules linked in: CPU: 1 PID: 7220 Comm: syz-executor380 Not tainted 6.9.0-syzkaller-07726-g3c999d1ae3c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:sock_map_close+0x2a2/0x2d0 net/core/sock_map.c:1701 Code: df e8 92 29 88 f8 48 8b 1b 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 79 29 88 f8 4c 8b 23 eb 89 e8 4f 15 23 f8 90 <0f> 0b 90 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d e9 13 26 3d 02 RSP: 0018:ffffc9000441fda8 EFLAGS: 00010293 RAX: ffffffff89731ae1 RBX: ffffffff94b87540 RCX: ffff888029470000 RDX: 0000000000000000 RSI: ffffffff8bcab5c0 RDI: ffffffff8c1faba0 RBP: 0000000000000000 R08: ffffffff92f9b61f R09: 1ffffffff25f36c3 R10: dffffc0000000000 R11: fffffbfff25f36c4 R12: ffffffff89731840 R13: ffff88804b587000 R14: ffff88804b587000 R15: ffffffff89731870 FS: 000055555e080380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000207d4000 CR4: 0000000000350ef0 Call Trace: <TASK> unix_release+0x87/0xc0 net/unix/af_unix.c:1048 __sock_release net/socket.c:659 [inline] sock_close+0xbe/0x240 net/socket.c:1421 __fput+0x42b/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb37d618070 Code: 00 00 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d4 e8 10 2c 00 00 80 3d 31 f0 07 00 00 74 17 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c RSP: 002b:00007ffcd4a525d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fb37d618070 RDX: 0000000000000010 RSI: 00000000200001c0 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000100000000 R09: 0000000100000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Use sk_psock, which will only check that the pointer is not been set to NULL yet, which should only happen after the callbacks are restored. If, then, a reference can still be gotten, we may call sk_psock_stop and cancel psock->work. As suggested by Paolo Abeni, reorder the condition so the control flow is less convoluted. After that change, the reproducer does not trigger the WARN_ON_ONCE anymore. | ||||
| CVE-2025-46397 | 2 Fig2dev Project, Redhat | 3 Fig2dev, Enterprise Linux, Rhel Eus | 2026-01-19 | 7.8 High |
| A flaw was found in xfig. This vulnerability allows possible code execution via local input manipulation via bezier_spline function. | ||||
| CVE-2024-41073 | 3 Debian, Linux, Redhat | 3 Debian Linux, Linux Kernel, Enterprise Linux | 2026-01-14 | 7.8 High |
| In the Linux kernel, the following vulnerability has been resolved: nvme: avoid double free special payload If a discard request needs to be retried, and that retry may fail before a new special payload is added, a double free will result. Clear the RQF_SPECIAL_LOAD when the request is cleaned. | ||||
| CVE-2024-56644 | 3 Debian, Linux, Redhat | 3 Debian Linux, Linux Kernel, Enterprise Linux | 2026-01-12 | 5.5 Medium |
| In the Linux kernel, the following vulnerability has been resolved: net/ipv6: release expired exception dst cached in socket Dst objects get leaked in ip6_negative_advice() when this function is executed for an expired IPv6 route located in the exception table. There are several conditions that must be fulfilled for the leak to occur: * an ICMPv6 packet indicating a change of the MTU for the path is received, resulting in an exception dst being created * a TCP connection that uses the exception dst for routing packets must start timing out so that TCP begins retransmissions * after the exception dst expires, the FIB6 garbage collector must not run before TCP executes ip6_negative_advice() for the expired exception dst When TCP executes ip6_negative_advice() for an exception dst that has expired and if no other socket holds a reference to the exception dst, the refcount of the exception dst is 2, which corresponds to the increment made by dst_init() and the increment made by the TCP socket for which the connection is timing out. The refcount made by the socket is never released. The refcount of the dst is decremented in sk_dst_reset() but that decrement is counteracted by a dst_hold() intentionally placed just before the sk_dst_reset() in ip6_negative_advice(). After ip6_negative_advice() has finished, there is no other object tied to the dst. The socket lost its reference stored in sk_dst_cache and the dst is no longer in the exception table. The exception dst becomes a leaked object. As a result of this dst leak, an unbalanced refcount is reported for the loopback device of a net namespace being destroyed under kernels that do not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"): unregister_netdevice: waiting for lo to become free. Usage count = 2 Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The patch that introduced the dst_hold() in ip6_negative_advice() was 92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22 merely refactored the code with regards to the dst refcount so the issue was present even before 92f1655aa2b22. The bug was introduced in 54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually expired.") where the expired cached route is deleted and the sk_dst_cache member of the socket is set to NULL by calling dst_negative_advice() but the refcount belonging to the socket is left unbalanced. The IPv4 version - ipv4_negative_advice() - is not affected by this bug. When the TCP connection times out ipv4_negative_advice() merely resets the sk_dst_cache of the socket while decrementing the refcount of the exception dst. | ||||