In the Linux kernel, the following vulnerability has been resolved: dccp: Fix memory leak in dccp_feat_change_recv If dccp_feat_push_confirm() fails after new value for SP feature was accepted without reconciliation ('entry == NULL' branch), memory allocated for that value with dccp_feat_clone_sp_val() is never freed. Here is the kmemleak stack for this: unreferenced object 0xffff88801d4ab488 (size 8): comm "syz-executor310", pid 1127, jiffies 4295085598 (age 41.666s) hex dump (first 8 bytes): 01 b4 4a 1d 80 88 ff ff ..J..... backtrace: [<00000000db7cabfe>] kmemdup+0x23/0x50 mm/util.c:128 [<0000000019b38405>] kmemdup include/linux/string.h:465 [inline] [<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:371 [inline] [<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:367 [inline] [<0000000019b38405>] dccp_feat_change_recv net/dccp/feat.c:1145 [inline] [<0000000019b38405>] dccp_feat_parse_options+0x1196/0x2180 net/dccp/feat.c:1416 [<00000000b1f6d94a>] dccp_parse_options+0xa2a/0x1260 net/dccp/options.c:125 [<0000000030d7b621>] dccp_rcv_state_process+0x197/0x13d0 net/dccp/input.c:650 [<000000001f74c72e>] dccp_v4_do_rcv+0xf9/0x1a0 net/dccp/ipv4.c:688 [<00000000a6c24128>] sk_backlog_rcv include/net/sock.h:1041 [inline] [<00000000a6c24128>] __release_sock+0x139/0x3b0 net/core/sock.c:2570 [<00000000cf1f3a53>] release_sock+0x54/0x1b0 net/core/sock.c:3111 [<000000008422fa23>] inet_wait_for_connect net/ipv4/af_inet.c:603 [inline] [<000000008422fa23>] __inet_stream_connect+0x5d0/0xf70 net/ipv4/af_inet.c:696 [<0000000015b6f64d>] inet_stream_connect+0x53/0xa0 net/ipv4/af_inet.c:735 [<0000000010122488>] __sys_connect_file+0x15c/0x1a0 net/socket.c:1865 [<00000000b4b70023>] __sys_connect+0x165/0x1a0 net/socket.c:1882 [<00000000f4cb3815>] __do_sys_connect net/socket.c:1892 [inline] [<00000000f4cb3815>] __se_sys_connect net/socket.c:1889 [inline] [<00000000f4cb3815>] __x64_sys_connect+0x6e/0xb0 net/socket.c:1889 [<00000000e7b1e839>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 [<0000000055e91434>] entry_SYSCALL_64_after_hwframe+0x67/0xd1 Clean up the allocated memory in case of dccp_feat_push_confirm() failure and bail out with an error reset code. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

In the Linux kernel, the following vulnerability has been resolved: fbdev: sh7760fb: Fix a possible memory leak in sh7760fb_alloc_mem() When information such as info->screen_base is not ready, calling sh7760fb_free_mem() does not release memory correctly. Call dma_free_coherent() instead.

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix qi_batch NULL pointer with nested parent domain The qi_batch is allocated when assigning cache tag for a domain. While for nested parent domain, it is missed. Hence, when trying to map pages to the nested parent, NULL dereference occurred. Also, there is potential memleak since there is no lock around domain->qi_batch allocation. To solve it, add a helper for qi_batch allocation, and call it in both the __cache_tag_assign_domain() and __cache_tag_assign_parent_domain(). BUG: kernel NULL pointer dereference, address: 0000000000000200 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8104795067 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 223 UID: 0 PID: 4357 Comm: qemu-system-x86 Not tainted 6.13.0-rc1-00028-g4b50c3c3b998-dirty #2632 Call Trace: ? __die+0x24/0x70 ? page_fault_oops+0x80/0x150 ? do_user_addr_fault+0x63/0x7b0 ? exc_page_fault+0x7c/0x220 ? asm_exc_page_fault+0x26/0x30 ? cache_tag_flush_range_np+0x13c/0x260 intel_iommu_iotlb_sync_map+0x1a/0x30 iommu_map+0x61/0xf0 batch_to_domain+0x188/0x250 iopt_area_fill_domains+0x125/0x320 ? rcu_is_watching+0x11/0x50 iopt_map_pages+0x63/0x100 iopt_map_common.isra.0+0xa7/0x190 iopt_map_user_pages+0x6a/0x80 iommufd_ioas_map+0xcd/0x1d0 iommufd_fops_ioctl+0x118/0x1c0 __x64_sys_ioctl+0x93/0xc0 do_syscall_64+0x71/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Several fixes to bpf_msg_pop_data Several fixes to bpf_msg_pop_data, 1. In sk_msg_shift_left, we should put_page 2. if (len == 0), return early is better 3. pop the entire sk_msg (last == msg->sg.size) should be supported 4. Fix for the value of variable "a" 5. In sk_msg_shift_left, after shifting, i has already pointed to the next element. Addtional sk_msg_iter_var_next may result in BUG.

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: pltfrm: Dellocate HBA during ufshcd_pltfrm_remove() This will ensure that the scsi host is cleaned up properly using scsi_host_dev_release(). Otherwise, it may lead to memory leaks.

In the Linux kernel, the following vulnerability has been resolved: PCI: Fix reset_method_store() memory leak In reset_method_store(), a string is allocated via kstrndup() and assigned to the local "options". options is then used in with strsep() to find spaces: while ((name = strsep(&options, " ")) != NULL) { If there are no remaining spaces, then options is set to NULL by strsep(), so the subsequent kfree(options) doesn't free the memory allocated via kstrndup(). Fix by using a separate tmp_options to iterate with strsep() so options is preserved.

In the Linux kernel, the following vulnerability has been resolved: wifi: rtlwifi: fix memory leaks and invalid access at probe error path Deinitialize at reverse order when probe fails. When init_sw_vars fails, rtl_deinit_core should not be called, specially now that it destroys the rtl_wq workqueue. And call rtl_pci_deinit and deinit_sw_vars, otherwise, memory will be leaked. Remove pci_set_drvdata call as it will already be cleaned up by the core driver code and could lead to memory leaks too. cf. commit 8d450935ae7f ("wireless: rtlwifi: remove unnecessary pci_set_drvdata()") and commit 3d86b93064c7 ("rtlwifi: Fix PCI probe error path orphaned memory").

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/gfx9: Add Cleaner Shader Deinitialization in gfx_v9_0 Module This commit addresses an omission in the previous patch related to the cleaner shader support for GFX9 hardware. Specifically, it adds the necessary deinitialization code for the cleaner shader in the gfx_v9_0_sw_fini function. The added line amdgpu_gfx_cleaner_shader_sw_fini(adev); ensures that any allocated resources for the cleaner shader are freed correctly, avoiding potential memory leaks and ensuring that the GPU state is clean for the next initialization sequence.

In the Linux kernel, the following vulnerability has been resolved: net: fix memory leak in tcp_conn_request() If inet_csk_reqsk_queue_hash_add() return false, tcp_conn_request() will return without free the dst memory, which allocated in af_ops->route_req. Here is the kmemleak stack: unreferenced object 0xffff8881198631c0 (size 240): comm "softirq", pid 0, jiffies 4299266571 (age 1802.392s) hex dump (first 32 bytes): 00 10 9b 03 81 88 ff ff 80 98 da bc ff ff ff ff ................ 81 55 18 bb ff ff ff ff 00 00 00 00 00 00 00 00 .U.............. backtrace: [<ffffffffb93e8d4c>] kmem_cache_alloc+0x60c/0xa80 [<ffffffffba11b4c5>] dst_alloc+0x55/0x250 [<ffffffffba227bf6>] rt_dst_alloc+0x46/0x1d0 [<ffffffffba23050a>] __mkroute_output+0x29a/0xa50 [<ffffffffba23456b>] ip_route_output_key_hash+0x10b/0x240 [<ffffffffba2346bd>] ip_route_output_flow+0x1d/0x90 [<ffffffffba254855>] inet_csk_route_req+0x2c5/0x500 [<ffffffffba26b331>] tcp_conn_request+0x691/0x12c0 [<ffffffffba27bd08>] tcp_rcv_state_process+0x3c8/0x11b0 [<ffffffffba2965c6>] tcp_v4_do_rcv+0x156/0x3b0 [<ffffffffba299c98>] tcp_v4_rcv+0x1cf8/0x1d80 [<ffffffffba239656>] ip_protocol_deliver_rcu+0xf6/0x360 [<ffffffffba2399a6>] ip_local_deliver_finish+0xe6/0x1e0 [<ffffffffba239b8e>] ip_local_deliver+0xee/0x360 [<ffffffffba239ead>] ip_rcv+0xad/0x2f0 [<ffffffffba110943>] __netif_receive_skb_one_core+0x123/0x140 Call dst_release() to free the dst memory when inet_csk_reqsk_queue_hash_add() return false in tcp_conn_request().

In the Linux kernel, the following vulnerability has been resolved: vfio/mlx5: Fix an unwind issue in mlx5vf_add_migration_pages() Fix an unwind issue in mlx5vf_add_migration_pages(). If a set of pages is allocated but fails to be added to the SG table, they need to be freed to prevent a memory leak. Any pages successfully added to the SG table will be freed as part of mlx5vf_free_data_buffer().

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: fix zcard and zqueue hot-unplug memleak Tests with kvm and a kmemdebug kernel showed, that on hot unplug the zcard and zqueue structs for the unplugged card or queue are not properly freed because of a mismatch with get/put for the embedded kref counter. This fix now adjusts the handling of the kref counters. With init the kref counter starts with 1. This initial value needs to drop to zero with the unregister of the card or queue to trigger the release and free the object.

In the Linux kernel, the following vulnerability has been resolved: sched/numa: fix memory leak due to the overwritten vma->numab_state [Problem Description] When running the hackbench program of LTP, the following memory leak is reported by kmemleak. # /opt/ltp/testcases/bin/hackbench 20 thread 1000 Running with 20*40 (== 800) tasks. # dmesg | grep kmemleak ... kmemleak: 480 new suspected memory leaks (see /sys/kernel/debug/kmemleak) kmemleak: 665 new suspected memory leaks (see /sys/kernel/debug/kmemleak) # cat /sys/kernel/debug/kmemleak unreferenced object 0xffff888cd8ca2c40 (size 64): comm "hackbench", pid 17142, jiffies 4299780315 hex dump (first 32 bytes): ac 74 49 00 01 00 00 00 4c 84 49 00 01 00 00 00 .tI.....L.I..... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc bff18fd4): [<ffffffff81419a89>] __kmalloc_cache_noprof+0x2f9/0x3f0 [<ffffffff8113f715>] task_numa_work+0x725/0xa00 [<ffffffff8110f878>] task_work_run+0x58/0x90 [<ffffffff81ddd9f8>] syscall_exit_to_user_mode+0x1c8/0x1e0 [<ffffffff81dd78d5>] do_syscall_64+0x85/0x150 [<ffffffff81e0012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e ... This issue can be consistently reproduced on three different servers: * a 448-core server * a 256-core server * a 192-core server [Root Cause] Since multiple threads are created by the hackbench program (along with the command argument 'thread'), a shared vma might be accessed by two or more cores simultaneously. When two or more cores observe that vma->numab_state is NULL at the same time, vma->numab_state will be overwritten. Although current code ensures that only one thread scans the VMAs in a single 'numa_scan_period', there might be a chance for another thread to enter in the next 'numa_scan_period' while we have not gotten till numab_state allocation [1]. Note that the command `/opt/ltp/testcases/bin/hackbench 50 process 1000` cannot the reproduce the issue. It is verified with 200+ test runs. [Solution] Use the cmpxchg atomic operation to ensure that only one thread executes the vma->numab_state assignment. [1] https://lore.kernel.org/lkml/1794be3c-358c-4cdc-a43d-a1f841d91ef7@amd.com/

In the Linux kernel, the following vulnerability has been resolved: virtiofs: fix memory leak in virtio_fs_probe() When accidentally passing twice the same tag to qemu, kmemleak ended up reporting a memory leak in virtiofs. Also, looking at the log I saw the following error (that's when I realised the duplicated tag): virtiofs: probe of virtio5 failed with error -17 Here's the kmemleak log for reference: unreferenced object 0xffff888103d47800 (size 1024): comm "systemd-udevd", pid 118, jiffies 4294893780 (age 18.340s) hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff 80 90 02 a0 ff ff ff ff ................ backtrace: [<000000000ebb87c1>] virtio_fs_probe+0x171/0x7ae [virtiofs] [<00000000f8aca419>] virtio_dev_probe+0x15f/0x210 [<000000004d6baf3c>] really_probe+0xea/0x430 [<00000000a6ceeac8>] device_driver_attach+0xa8/0xb0 [<00000000196f47a7>] __driver_attach+0x98/0x140 [<000000000b20601d>] bus_for_each_dev+0x7b/0xc0 [<00000000399c7b7f>] bus_add_driver+0x11b/0x1f0 [<0000000032b09ba7>] driver_register+0x8f/0xe0 [<00000000cdd55998>] 0xffffffffa002c013 [<000000000ea196a2>] do_one_initcall+0x64/0x2e0 [<0000000008f727ce>] do_init_module+0x5c/0x260 [<000000003cdedab6>] __do_sys_finit_module+0xb5/0x120 [<00000000ad2f48c6>] do_syscall_64+0x33/0x40 [<00000000809526b5>] entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix memory leak in fib6_rule_suppress The kernel leaks memory when a `fib` rule is present in IPv6 nftables firewall rules and a suppress_prefix rule is present in the IPv6 routing rules (used by certain tools such as wg-quick). In such scenarios, every incoming packet will leak an allocation in `ip6_dst_cache` slab cache. After some hours of `bpftrace`-ing and source code reading, I tracked down the issue to ca7a03c41753 ("ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule"). The problem with that change is that the generic `args->flags` always have `FIB_LOOKUP_NOREF` set[1][2] but the IPv6-specific flag `RT6_LOOKUP_F_DST_NOREF` might not be, leading to `fib6_rule_suppress` not decreasing the refcount when needed. How to reproduce: - Add the following nftables rule to a prerouting chain: meta nfproto ipv6 fib saddr . mark . iif oif missing drop This can be done with: sudo nft create table inet test sudo nft create chain inet test test_chain '{ type filter hook prerouting priority filter + 10; policy accept; }' sudo nft add rule inet test test_chain meta nfproto ipv6 fib saddr . mark . iif oif missing drop - Run: sudo ip -6 rule add table main suppress_prefixlength 0 - Watch `sudo slabtop -o | grep ip6_dst_cache` to see memory usage increase with every incoming ipv6 packet. This patch exposes the protocol-specific flags to the protocol specific `suppress` function, and check the protocol-specific `flags` argument for RT6_LOOKUP_F_DST_NOREF instead of the generic FIB_LOOKUP_NOREF when decreasing the refcount, like this. [1]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L71 [2]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L99

In the Linux kernel, the following vulnerability has been resolved: net: rds: fix memory leak in rds_recvmsg Syzbot reported memory leak in rds. The problem was in unputted refcount in case of error. int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int msg_flags) { ... if (!rds_next_incoming(rs, &inc)) { ... } After this "if" inc refcount incremented and if (rds_cmsg_recv(inc, msg, rs)) { ret = -EFAULT; goto out; } ... out: return ret; } in case of rds_cmsg_recv() fail the refcount won't be decremented. And it's easy to see from ftrace log, that rds_inc_addref() don't have rds_inc_put() pair in rds_recvmsg() after rds_cmsg_recv() 1) | rds_recvmsg() { 1) 3.721 us | rds_inc_addref(); 1) 3.853 us | rds_message_inc_copy_to_user(); 1) + 10.395 us | rds_cmsg_recv(); 1) + 34.260 us | }

In the Linux kernel, the following vulnerability has been resolved: octeontx2-af: Fix a memleak bug in rvu_mbox_init() In rvu_mbox_init(), mbox_regions is not freed or passed out under the switch-default region, which could lead to a memory leak. Fix this bug by changing 'return err' to 'goto free_regions'. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_OCTEONTX2_AF=y show no new warnings, and our static analyzer no longer warns about this code.

In the Linux kernel, the following vulnerability has been resolved: NFC: nci: fix memory leak in nci_allocate_device nfcmrvl_disconnect fails to free the hci_dev field in struct nci_dev. Fix this by freeing hci_dev in nci_free_device. BUG: memory leak unreferenced object 0xffff888111ea6800 (size 1024): comm "kworker/1:0", pid 19, jiffies 4294942308 (age 13.580s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 60 fd 0c 81 88 ff ff .........`...... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000004bc25d43>] kmalloc include/linux/slab.h:552 [inline] [<000000004bc25d43>] kzalloc include/linux/slab.h:682 [inline] [<000000004bc25d43>] nci_hci_allocate+0x21/0xd0 net/nfc/nci/hci.c:784 [<00000000c59cff92>] nci_allocate_device net/nfc/nci/core.c:1170 [inline] [<00000000c59cff92>] nci_allocate_device+0x10b/0x160 net/nfc/nci/core.c:1132 [<00000000006e0a8e>] nfcmrvl_nci_register_dev+0x10a/0x1c0 drivers/nfc/nfcmrvl/main.c:153 [<000000004da1b57e>] nfcmrvl_probe+0x223/0x290 drivers/nfc/nfcmrvl/usb.c:345 [<00000000d506aed9>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396 [<00000000bc632c92>] really_probe+0x159/0x4a0 drivers/base/dd.c:554 [<00000000f5009125>] driver_probe_device+0x84/0x100 drivers/base/dd.c:740 [<000000000ce658ca>] __device_attach_driver+0xee/0x110 drivers/base/dd.c:846 [<000000007067d05f>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:431 [<00000000f8e13372>] __device_attach+0x122/0x250 drivers/base/dd.c:914 [<000000009cf68860>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:491 [<00000000359c965a>] device_add+0x5be/0xc30 drivers/base/core.c:3109 [<00000000086e4bd3>] usb_set_configuration+0x9d9/0xb90 drivers/usb/core/message.c:2164 [<00000000ca036872>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238 [<00000000d40d36f6>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293 [<00000000bc632c92>] really_probe+0x159/0x4a0 drivers/base/dd.c:554

In the Linux kernel, the following vulnerability has been resolved: libbpf: Fix memory leak in strset Free struct strset itself, not just its internal parts.

In the Linux kernel, the following vulnerability has been resolved: net: hamradio: fix memory leak in mkiss_close My local syzbot instance hit memory leak in mkiss_open()[1]. The problem was in missing free_netdev() in mkiss_close(). In mkiss_open() netdevice is allocated and then registered, but in mkiss_close() netdevice was only unregistered, but not freed. Fail log: BUG: memory leak unreferenced object 0xffff8880281ba000 (size 4096): comm "syz-executor.1", pid 11443, jiffies 4295046091 (age 17.660s) hex dump (first 32 bytes): 61 78 30 00 00 00 00 00 00 00 00 00 00 00 00 00 ax0............. 00 27 fa 2a 80 88 ff ff 00 00 00 00 00 00 00 00 .'.*............ backtrace: [<ffffffff81a27201>] kvmalloc_node+0x61/0xf0 [<ffffffff8706e7e8>] alloc_netdev_mqs+0x98/0xe80 [<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1] [<ffffffff842355db>] tty_ldisc_open+0x9b/0x110 [<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670 [<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440 [<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200 [<ffffffff8911263a>] do_syscall_64+0x3a/0xb0 [<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae BUG: memory leak unreferenced object 0xffff8880141a9a00 (size 96): comm "syz-executor.1", pid 11443, jiffies 4295046091 (age 17.660s) hex dump (first 32 bytes): e8 a2 1b 28 80 88 ff ff e8 a2 1b 28 80 88 ff ff ...(.......(.... 98 92 9c aa b0 40 02 00 00 00 00 00 00 00 00 00 .....@.......... backtrace: [<ffffffff8709f68b>] __hw_addr_create_ex+0x5b/0x310 [<ffffffff8709fb38>] __hw_addr_add_ex+0x1f8/0x2b0 [<ffffffff870a0c7b>] dev_addr_init+0x10b/0x1f0 [<ffffffff8706e88b>] alloc_netdev_mqs+0x13b/0xe80 [<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1] [<ffffffff842355db>] tty_ldisc_open+0x9b/0x110 [<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670 [<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440 [<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200 [<ffffffff8911263a>] do_syscall_64+0x3a/0xb0 [<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae BUG: memory leak unreferenced object 0xffff8880219bfc00 (size 512): comm "syz-executor.1", pid 11443, jiffies 4295046091 (age 17.660s) hex dump (first 32 bytes): 00 a0 1b 28 80 88 ff ff 80 8f b1 8d ff ff ff ff ...(............ 80 8f b1 8d ff ff ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81a27201>] kvmalloc_node+0x61/0xf0 [<ffffffff8706eec7>] alloc_netdev_mqs+0x777/0xe80 [<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1] [<ffffffff842355db>] tty_ldisc_open+0x9b/0x110 [<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670 [<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440 [<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200 [<ffffffff8911263a>] do_syscall_64+0x3a/0xb0 [<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae BUG: memory leak unreferenced object 0xffff888029b2b200 (size 256): comm "syz-executor.1", pid 11443, jiffies 4295046091 (age 17.660s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81a27201>] kvmalloc_node+0x61/0xf0 [<ffffffff8706f062>] alloc_netdev_mqs+0x912/0xe80 [<ffffffff84e64192>] mkiss_open+0xb2/0x6f0 [1] [<ffffffff842355db>] tty_ldisc_open+0x9b/0x110 [<ffffffff84236488>] tty_set_ldisc+0x2e8/0x670 [<ffffffff8421f7f3>] tty_ioctl+0xda3/0x1440 [<ffffffff81c9f273>] __x64_sys_ioctl+0x193/0x200 [<ffffffff8911263a>] do_syscall_64+0x3a/0xb0 [<ffffffff89200068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: netfilter: nftables: Fix a memleak from userdata error path in new objects Release object name if userdata allocation fails.

In the Linux kernel, the following vulnerability has been resolved: rpcrdma: Always release the rpcrdma_device's xa_array Dai pointed out that the xa_init_flags() in rpcrdma_add_one() needs to have a matching xa_destroy() in rpcrdma_remove_one() to release underlying memory that the xarray might have accrued during operation.

In the Linux kernel, the following vulnerability has been resolved: scsi: pm80xx: Fix memory leak during rmmod Driver failed to release all memory allocated. This would lead to memory leak during driver removal. Properly free memory when the module is removed.

In the Linux kernel, the following vulnerability has been resolved: iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove When ACPI type is ACPI_SMO8500, the data->dready_trig will not be set, the memory allocated by iio_triggered_buffer_setup() will not be freed, and cause memory leak as follows: unreferenced object 0xffff888009551400 (size 512): comm "i2c-SMO8500-125", pid 911, jiffies 4294911787 (age 83.852s) hex dump (first 32 bytes): 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 20 e2 e5 c0 ff ff ff ff ........ ....... backtrace: [<0000000041ce75ee>] kmem_cache_alloc_trace+0x16d/0x360 [<000000000aeb17b0>] iio_kfifo_allocate+0x41/0x130 [kfifo_buf] [<000000004b40c1f5>] iio_triggered_buffer_setup_ext+0x2c/0x210 [industrialio_triggered_buffer] [<000000004375b15f>] kxcjk1013_probe+0x10c3/0x1d81 [kxcjk_1013] Fix it by remove data->dready_trig condition in probe and remove.

In the Linux kernel, the following vulnerability has been resolved: nfp: Fix memory leak in nfp_cpp_area_cache_add() In line 800 (#1), nfp_cpp_area_alloc() allocates and initializes a CPP area structure. But in line 807 (#2), when the cache is allocated failed, this CPP area structure is not freed, which will result in memory leak. We can fix it by freeing the CPP area when the cache is allocated failed (#2). 792 int nfp_cpp_area_cache_add(struct nfp_cpp *cpp, size_t size) 793 { 794 struct nfp_cpp_area_cache *cache; 795 struct nfp_cpp_area *area; 800 area = nfp_cpp_area_alloc(cpp, NFP_CPP_ID(7, NFP_CPP_ACTION_RW, 0), 801 0, size); // #1: allocates and initializes 802 if (!area) 803 return -ENOMEM; 805 cache = kzalloc(sizeof(*cache), GFP_KERNEL); 806 if (!cache) 807 return -ENOMEM; // #2: missing free 817 return 0; 818 }

In the Linux kernel, the following vulnerability has been resolved: virtio/vsock: Fix accept_queue memory leak As the final stages of socket destruction may be delayed, it is possible that virtio_transport_recv_listen() will be called after the accept_queue has been flushed, but before the SOCK_DONE flag has been set. As a result, sockets enqueued after the flush would remain unremoved, leading to a memory leak. vsock_release __vsock_release lock virtio_transport_release virtio_transport_close schedule_delayed_work(close_work) sk_shutdown = SHUTDOWN_MASK (!) flush accept_queue release virtio_transport_recv_pkt vsock_find_bound_socket lock if flag(SOCK_DONE) return virtio_transport_recv_listen child = vsock_create_connected (!) vsock_enqueue_accept(child) release close_work lock virtio_transport_do_close set_flag(SOCK_DONE) virtio_transport_remove_sock vsock_remove_sock vsock_remove_bound release Introduce a sk_shutdown check to disallow vsock_enqueue_accept() during socket destruction. unreferenced object 0xffff888109e3f800 (size 2040): comm "kworker/5:2", pid 371, jiffies 4294940105 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 28 00 0b 40 00 00 00 00 00 00 00 00 00 00 00 00 (..@............ backtrace (crc 9e5f4e84): [<ffffffff81418ff1>] kmem_cache_alloc_noprof+0x2c1/0x360 [<ffffffff81d27aa0>] sk_prot_alloc+0x30/0x120 [<ffffffff81d2b54c>] sk_alloc+0x2c/0x4b0 [<ffffffff81fe049a>] __vsock_create.constprop.0+0x2a/0x310 [<ffffffff81fe6d6c>] virtio_transport_recv_pkt+0x4dc/0x9a0 [<ffffffff81fe745d>] vsock_loopback_work+0xfd/0x140 [<ffffffff810fc6ac>] process_one_work+0x20c/0x570 [<ffffffff810fce3f>] worker_thread+0x1bf/0x3a0 [<ffffffff811070dd>] kthread+0xdd/0x110 [<ffffffff81044fdd>] ret_from_fork+0x2d/0x50 [<ffffffff8100785a>] ret_from_fork_asm+0x1a/0x30

In the Linux kernel, the following vulnerability has been resolved: ipc: fix memleak if msg_init_ns failed in create_ipc_ns Percpu memory allocation may failed during create_ipc_ns however this fail is not handled properly since ipc sysctls and mq sysctls is not released properly. Fix this by release these two resource when failure. Here is the kmemleak stack when percpu failed: unreferenced object 0xffff88819de2a600 (size 512): comm "shmem_2nstest", pid 120711, jiffies 4300542254 hex dump (first 32 bytes): 60 aa 9d 84 ff ff ff ff fc 18 48 b2 84 88 ff ff `.........H..... 04 00 00 00 a4 01 00 00 20 e4 56 81 ff ff ff ff ........ .V..... backtrace (crc be7cba35): [<ffffffff81b43f83>] __kmalloc_node_track_caller_noprof+0x333/0x420 [<ffffffff81a52e56>] kmemdup_noprof+0x26/0x50 [<ffffffff821b2f37>] setup_mq_sysctls+0x57/0x1d0 [<ffffffff821b29cc>] copy_ipcs+0x29c/0x3b0 [<ffffffff815d6a10>] create_new_namespaces+0x1d0/0x920 [<ffffffff815d7449>] copy_namespaces+0x2e9/0x3e0 [<ffffffff815458f3>] copy_process+0x29f3/0x7ff0 [<ffffffff8154b080>] kernel_clone+0xc0/0x650 [<ffffffff8154b6b1>] __do_sys_clone+0xa1/0xe0 [<ffffffff843df8ff>] do_syscall_64+0xbf/0x1c0 [<ffffffff846000b0>] entry_SYSCALL_64_after_hwframe+0x4b/0x53

In the Linux kernel, the following vulnerability has been resolved: mt76: mt7615: fix tx skb dma unmap The first pointer in the txp needs to be unmapped as well, otherwise it will leak DMA mapping entries

In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in ext4_mb_init_backend on error path. Fix a memory leak discovered by syzbot when a file system is corrupted with an illegally large s_log_groups_per_flex.

In the Linux kernel, the following vulnerability has been resolved: mm/damon/tests/sysfs-kunit.h: fix memory leak in damon_sysfs_test_add_targets() The sysfs_target->regions allocated in damon_sysfs_regions_alloc() is not freed in damon_sysfs_test_add_targets(), which cause the following memory leak, free it to fix it. unreferenced object 0xffffff80c2a8db80 (size 96): comm "kunit_try_catch", pid 187, jiffies 4294894363 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<0000000001e3714d>] kmemleak_alloc+0x34/0x40 [<000000008e6835c1>] __kmalloc_cache_noprof+0x26c/0x2f4 [<000000001286d9f8>] damon_sysfs_test_add_targets+0x1cc/0x738 [<0000000032ef8f77>] kunit_try_run_case+0x13c/0x3ac [<00000000f3edea23>] kunit_generic_run_threadfn_adapter+0x80/0xec [<00000000adf936cf>] kthread+0x2e8/0x374 [<0000000041bb1628>] ret_from_fork+0x10/0x20

In the Linux kernel, the following vulnerability has been resolved: RDMA/bnxt_re: Fix a possible memory leak In bnxt_re_setup_chip_ctx() when bnxt_qplib_map_db_bar() fails driver is not freeing the memory allocated for "rdev->chip_ctx".

In the Linux kernel, the following vulnerability has been resolved: exfat: fix memory leak in exfat_load_bitmap() If the first directory entry in the root directory is not a bitmap directory entry, 'bh' will not be released and reassigned, which will cause a memory leak.

In the Linux kernel, the following vulnerability has been resolved: zram: free secondary algorithms names We need to kfree() secondary algorithms names when reset zram device that had multi-streams, otherwise we leak memory. [senozhatsky@chromium.org: kfree(NULL) is legal]

In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak vcpu_put is not called if the user copy fails. This can result in preempt notifier corruption and crashes, among other issues.

In the Linux kernel, the following vulnerability has been resolved: drm/tests: hdmi: Fix memory leaks in drm_display_mode_from_cea_vic() modprobe drm_hdmi_state_helper_test and then rmmod it, the following memory leak occurs. The `mode` allocated in drm_mode_duplicate() called by drm_display_mode_from_cea_vic() is not freed, which cause the memory leak: unreferenced object 0xffffff80ccd18100 (size 128): comm "kunit_try_catch", pid 1851, jiffies 4295059695 hex dump (first 32 bytes): 57 62 00 00 80 02 90 02 f0 02 20 03 00 00 e0 01 Wb........ ..... ea 01 ec 01 0d 02 00 00 0a 00 00 00 00 00 00 00 ................ backtrace (crc c2f1aa95): [<000000000f10b11b>] kmemleak_alloc+0x34/0x40 [<000000001cd4cf73>] __kmalloc_cache_noprof+0x26c/0x2f4 [<00000000f1f3cffa>] drm_mode_duplicate+0x44/0x19c [<000000008cbeef13>] drm_display_mode_from_cea_vic+0x88/0x98 [<0000000019daaacf>] 0xffffffedc11ae69c [<000000000aad0f85>] kunit_try_run_case+0x13c/0x3ac [<00000000a9210bac>] kunit_generic_run_threadfn_adapter+0x80/0xec [<000000000a0b2e9e>] kthread+0x2e8/0x374 [<00000000bd668858>] ret_from_fork+0x10/0x20 ...... Free `mode` by using drm_kunit_display_mode_from_cea_vic() to fix it.

In the Linux kernel, the following vulnerability has been resolved: mlxsw: spectrum_ipip: Fix memory leak when changing remote IPv6 address The device stores IPv6 addresses that are used for encapsulation in linear memory that is managed by the driver. Changing the remote address of an ip6gre net device never worked properly, but since cited commit the following reproducer [1] would result in a warning [2] and a memory leak [3]. The problem is that the new remote address is never added by the driver to its hash table (and therefore the device) and the old address is never removed from it. Fix by programming the new address when the configuration of the ip6gre net device changes and removing the old one. If the address did not change, then the above would result in increasing the reference count of the address and then decreasing it. [1] # ip link add name bla up type ip6gre local 2001:db8:1::1 remote 2001:db8:2::1 tos inherit ttl inherit # ip link set dev bla type ip6gre remote 2001:db8:3::1 # ip link del dev bla # devlink dev reload pci/0000:01:00.0 [2] WARNING: CPU: 0 PID: 1682 at drivers/net/ethernet/mellanox/mlxsw/spectrum.c:3002 mlxsw_sp_ipv6_addr_put+0x140/0x1d0 Modules linked in: CPU: 0 UID: 0 PID: 1682 Comm: ip Not tainted 6.12.0-rc3-custom-g86b5b55bc835 #151 Hardware name: Nvidia SN5600/VMOD0013, BIOS 5.13 05/31/2023 RIP: 0010:mlxsw_sp_ipv6_addr_put+0x140/0x1d0 [...] Call Trace: <TASK> mlxsw_sp_router_netdevice_event+0x55f/0x1240 notifier_call_chain+0x5a/0xd0 call_netdevice_notifiers_info+0x39/0x90 unregister_netdevice_many_notify+0x63e/0x9d0 rtnl_dellink+0x16b/0x3a0 rtnetlink_rcv_msg+0x142/0x3f0 netlink_rcv_skb+0x50/0x100 netlink_unicast+0x242/0x390 netlink_sendmsg+0x1de/0x420 ____sys_sendmsg+0x2bd/0x320 ___sys_sendmsg+0x9a/0xe0 __sys_sendmsg+0x7a/0xd0 do_syscall_64+0x9e/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f [3] unreferenced object 0xffff898081f597a0 (size 32): comm "ip", pid 1626, jiffies 4294719324 hex dump (first 32 bytes): 20 01 0d b8 00 02 00 00 00 00 00 00 00 00 00 01 ............... 21 49 61 83 80 89 ff ff 00 00 00 00 01 00 00 00 !Ia............. backtrace (crc fd9be911): [<00000000df89c55d>] __kmalloc_cache_noprof+0x1da/0x260 [<00000000ff2a1ddb>] mlxsw_sp_ipv6_addr_kvdl_index_get+0x281/0x340 [<000000009ddd445d>] mlxsw_sp_router_netdevice_event+0x47b/0x1240 [<00000000743e7757>] notifier_call_chain+0x5a/0xd0 [<000000007c7b9e13>] call_netdevice_notifiers_info+0x39/0x90 [<000000002509645d>] register_netdevice+0x5f7/0x7a0 [<00000000c2e7d2a9>] ip6gre_newlink_common.isra.0+0x65/0x130 [<0000000087cd6d8d>] ip6gre_newlink+0x72/0x120 [<000000004df7c7cc>] rtnl_newlink+0x471/0xa20 [<0000000057ed632a>] rtnetlink_rcv_msg+0x142/0x3f0 [<0000000032e0d5b5>] netlink_rcv_skb+0x50/0x100 [<00000000908bca63>] netlink_unicast+0x242/0x390 [<00000000cdbe1c87>] netlink_sendmsg+0x1de/0x420 [<0000000011db153e>] ____sys_sendmsg+0x2bd/0x320 [<000000003b6d53eb>] ___sys_sendmsg+0x9a/0xe0 [<00000000cae27c62>] __sys_sendmsg+0x7a/0xd0

In the Linux kernel, the following vulnerability has been resolved: drm/connector: hdmi: Fix memory leak in drm_display_mode_from_cea_vic() modprobe drm_connector_test and then rmmod drm_connector_test, the following memory leak occurs. The `mode` allocated in drm_mode_duplicate() called by drm_display_mode_from_cea_vic() is not freed, which cause the memory leak: unreferenced object 0xffffff80cb0ee400 (size 128): comm "kunit_try_catch", pid 1948, jiffies 4294950339 hex dump (first 32 bytes): 14 44 02 00 80 07 d8 07 04 08 98 08 00 00 38 04 .D............8. 3c 04 41 04 65 04 00 00 05 00 00 00 00 00 00 00 <.A.e........... backtrace (crc 90e9585c): [<00000000ec42e3d7>] kmemleak_alloc+0x34/0x40 [<00000000d0ef055a>] __kmalloc_cache_noprof+0x26c/0x2f4 [<00000000c2062161>] drm_mode_duplicate+0x44/0x19c [<00000000f96c74aa>] drm_display_mode_from_cea_vic+0x88/0x98 [<00000000d8f2c8b4>] 0xffffffdc982a4868 [<000000005d164dbc>] kunit_try_run_case+0x13c/0x3ac [<000000006fb23398>] kunit_generic_run_threadfn_adapter+0x80/0xec [<000000006ea56ca0>] kthread+0x2e8/0x374 [<000000000676063f>] ret_from_fork+0x10/0x20 ...... Free `mode` by using drm_kunit_display_mode_from_cea_vic() to fix it.

In the Linux kernel, the following vulnerability has been resolved: mt76: mt7915: fix memleak when mt7915_unregister_device() mt7915_tx_token_put() should get call before mt76_free_pending_txwi().

In the Linux kernel, the following vulnerability has been resolved: platform/x86: intel_pmc_core: fix memleak on registration failure In case device registration fails during module initialisation, the platform device structure needs to be freed using platform_device_put() to properly free all resources (e.g. the device name).

In the Linux kernel, the following vulnerability has been resolved: ptp: Fix possible memory leak in ptp_clock_register() I got memory leak as follows when doing fault injection test: unreferenced object 0xffff88800906c618 (size 8): comm "i2c-idt82p33931", pid 4421, jiffies 4294948083 (age 13.188s) hex dump (first 8 bytes): 70 74 70 30 00 00 00 00 ptp0.... backtrace: [<00000000312ed458>] __kmalloc_track_caller+0x19f/0x3a0 [<0000000079f6e2ff>] kvasprintf+0xb5/0x150 [<0000000026aae54f>] kvasprintf_const+0x60/0x190 [<00000000f323a5f7>] kobject_set_name_vargs+0x56/0x150 [<000000004e35abdd>] dev_set_name+0xc0/0x100 [<00000000f20cfe25>] ptp_clock_register+0x9f4/0xd30 [ptp] [<000000008bb9f0de>] idt82p33_probe.cold+0x8b6/0x1561 [ptp_idt82p33] When posix_clock_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used to give up the device reference, then the name will be freed in kobject_cleanup() and other memory will be freed in ptp_clock_release().

In the Linux kernel, the following vulnerability has been resolved: net: fec: fix the potential memory leak in fec_enet_init() If the memory allocated for cbd_base is failed, it should free the memory allocated for the queues, otherwise it causes memory leak. And if the memory allocated for the queues is failed, it can return error directly.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix memory leak in mlx5_core_destroy_cq() error path Prior to this patch in case mlx5_core_destroy_cq() failed it returns without completing all destroy operations and that leads to memory leak. Instead, complete the destroy flow before return error. Also move mlx5_debug_cq_remove() to the beginning of mlx5_core_destroy_cq() to be symmetrical with mlx5_core_create_cq(). kmemleak complains on: unreferenced object 0xc000000038625100 (size 64): comm "ethtool", pid 28301, jiffies 4298062946 (age 785.380s) hex dump (first 32 bytes): 60 01 48 94 00 00 00 c0 b8 05 34 c3 00 00 00 c0 `.H.......4..... 02 00 00 00 00 00 00 00 00 db 7d c1 00 00 00 c0 ..........}..... backtrace: [<000000009e8643cb>] add_res_tree+0xd0/0x270 [mlx5_core] [<00000000e7cb8e6c>] mlx5_debug_cq_add+0x5c/0xc0 [mlx5_core] [<000000002a12918f>] mlx5_core_create_cq+0x1d0/0x2d0 [mlx5_core] [<00000000cef0a696>] mlx5e_create_cq+0x210/0x3f0 [mlx5_core] [<000000009c642c26>] mlx5e_open_cq+0xb4/0x130 [mlx5_core] [<0000000058dfa578>] mlx5e_ptp_open+0x7f4/0xe10 [mlx5_core] [<0000000081839561>] mlx5e_open_channels+0x9cc/0x13e0 [mlx5_core] [<0000000009cf05d4>] mlx5e_switch_priv_channels+0xa4/0x230 [mlx5_core] [<0000000042bbedd8>] mlx5e_safe_switch_params+0x14c/0x300 [mlx5_core] [<0000000004bc9db8>] set_pflag_tx_port_ts+0x9c/0x160 [mlx5_core] [<00000000a0553443>] mlx5e_set_priv_flags+0xd0/0x1b0 [mlx5_core] [<00000000a8f3d84b>] ethnl_set_privflags+0x234/0x2d0 [<00000000fd27f27c>] genl_family_rcv_msg_doit+0x108/0x1d0 [<00000000f495e2bb>] genl_family_rcv_msg+0xe4/0x1f0 [<00000000646c5c2c>] genl_rcv_msg+0x78/0x120 [<00000000d53e384e>] netlink_rcv_skb+0x74/0x1a0

In the Linux kernel, the following vulnerability has been resolved: NFC: st21nfca: Fix memory leak in device probe and remove 'phy->pending_skb' is alloced when device probe, but forgot to free in the error handling path and remove path, this cause memory leak as follows: unreferenced object 0xffff88800bc06800 (size 512): comm "8", pid 11775, jiffies 4295159829 (age 9.032s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000d66c09ce>] __kmalloc_node_track_caller+0x1ed/0x450 [<00000000c93382b3>] kmalloc_reserve+0x37/0xd0 [<000000005fea522c>] __alloc_skb+0x124/0x380 [<0000000019f29f9a>] st21nfca_hci_i2c_probe+0x170/0x8f2 Fix it by freeing 'pending_skb' in error and remove.

In the Linux kernel, the following vulnerability has been resolved: crypto: sun8i-ss - Fix memory leak of pad It appears there are several failure return paths that don't seem to be free'ing pad. Fix these. Addresses-Coverity: ("Resource leak")

In the Linux kernel, the following vulnerability has been resolved: bpf, s390: Fix potential memory leak about jit_data Make sure to free jit_data through kfree() in the error path.

In the Linux kernel, the following vulnerability has been resolved: iwlwifi: Fix memory leaks in error handling path Should an error occur (invalid TLV len or memory allocation failure), the memory already allocated in 'reduce_power_data' should be freed before returning, otherwise it is leaking.

mwifiex_tm_cmd in drivers/net/wireless/marvell/mwifiex/cfg80211.c in the Linux kernel before 5.1.6 has some error-handling cases that did not free allocated hostcmd memory, aka CID-003b686ace82. This will cause a memory leak and denial of service.

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: fix a potential ttm->sg memory leak Memory is allocated for ttm->sg by kmalloc in kfd_mem_dmamap_userptr, but isn't freed by kfree in kfd_mem_dmaunmap_userptr. Free it!

In the Linux kernel, the following vulnerability has been resolved: hugetlb, userfaultfd: fix reservation restore on userfaultfd error Currently in the is_continue case in hugetlb_mcopy_atomic_pte(), if we bail out using "goto out_release_unlock;" in the cases where idx >= size, or !huge_pte_none(), the code will detect that new_pagecache_page == false, and so call restore_reserve_on_error(). In this case I see restore_reserve_on_error() delete the reservation, and the following call to remove_inode_hugepages() will increment h->resv_hugepages causing a 100% reproducible leak. We should treat the is_continue case similar to adding a page into the pagecache and set new_pagecache_page to true, to indicate that there is no reservation to restore on the error path, and we need not call restore_reserve_on_error(). Rename new_pagecache_page to page_in_pagecache to make that clear.

In the Linux kernel, the following vulnerability has been resolved: media: staging/intel-ipu3: Fix memory leak in imu_fmt We are losing the reference to an allocated memory if try. Change the order of the check to avoid that.

In the Linux kernel, the following vulnerability has been resolved: ext4: fix memory leak in ext4_fill_super Buffer head references must be released before calling kill_bdev(); otherwise the buffer head (and its page referenced by b_data) will not be freed by kill_bdev, and subsequently that bh will be leaked. If blocksizes differ, sb_set_blocksize() will kill current buffers and page cache by using kill_bdev(). And then super block will be reread again but using correct blocksize this time. sb_set_blocksize() didn't fully free superblock page and buffer head, and being busy, they were not freed and instead leaked. This can easily be reproduced by calling an infinite loop of: systemctl start <ext4_on_lvm>.mount, and systemctl stop <ext4_on_lvm>.mount ... since systemd creates a cgroup for each slice which it mounts, and the bh leak get amplified by a dying memory cgroup that also never gets freed, and memory consumption is much more easily noticed.