{"id":"AZL-70427","summary":"CVE-2025-38232 affecting package kernel 5.15.200.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: fix race between nfsd registration and exports_proc\n\nAs of now nfsd calls create_proc_exports_entry() at start of init_nfsd\nand cleanup by remove_proc_entry() at last of exit_nfsd.\n\nWhich causes kernel OOPs if there is race between below 2 operations:\n(i) exportfs -r\n(ii) mount -t nfsd none /proc/fs/nfsd\n\nfor 5.4 kernel ARM64:\n\nCPU 1:\nel1_irq+0xbc/0x180\narch_counter_get_cntvct+0x14/0x18\nrunning_clock+0xc/0x18\npreempt_count_add+0x88/0x110\nprep_new_page+0xb0/0x220\nget_page_from_freelist+0x2d8/0x1778\n__alloc_pages_nodemask+0x15c/0xef0\n__vmalloc_node_range+0x28c/0x478\n__vmalloc_node_flags_caller+0x8c/0xb0\nkvmalloc_node+0x88/0xe0\nnfsd_init_net+0x6c/0x108 [nfsd]\nops_init+0x44/0x170\nregister_pernet_operations+0x114/0x270\nregister_pernet_subsys+0x34/0x50\ninit_nfsd+0xa8/0x718 [nfsd]\ndo_one_initcall+0x54/0x2e0\n\nCPU 2 :\nUnable to handle kernel NULL pointer dereference at virtual address 0000000000000010\n\nPC is at : exports_net_open+0x50/0x68 [nfsd]\n\nCall trace:\nexports_net_open+0x50/0x68 [nfsd]\nexports_proc_open+0x2c/0x38 [nfsd]\nproc_reg_open+0xb8/0x198\ndo_dentry_open+0x1c4/0x418\nvfs_open+0x38/0x48\npath_openat+0x28c/0xf18\ndo_filp_open+0x70/0xe8\ndo_sys_open+0x154/0x248\n\nSometimes it crashes at exports_net_open() and sometimes cache_seq_next_rcu().\n\nand same is happening on latest 6.14 kernel as well:\n\n[    0.000000] Linux version 6.14.0-rc5-next-20250304-dirty\n...\n[  285.455918] Unable to handle kernel paging request at virtual address 00001f4800001f48\n...\n[  285.464902] pc : cache_seq_next_rcu+0x78/0xa4\n...\n[  285.469695] Call trace:\n[  285.470083]  cache_seq_next_rcu+0x78/0xa4 (P)\n[  285.470488]  seq_read+0xe0/0x11c\n[  285.470675]  proc_reg_read+0x9c/0xf0\n[  285.470874]  vfs_read+0xc4/0x2fc\n[  285.471057]  ksys_read+0x6c/0xf4\n[  285.471231]  __arm64_sys_read+0x1c/0x28\n[  285.471428]  invoke_syscall+0x44/0x100\n[  285.471633]  el0_svc_common.constprop.0+0x40/0xe0\n[  285.471870]  do_el0_svc_compat+0x1c/0x34\n[  285.472073]  el0_svc_compat+0x2c/0x80\n[  285.472265]  el0t_32_sync_handler+0x90/0x140\n[  285.472473]  el0t_32_sync+0x19c/0x1a0\n[  285.472887] Code: f9400885 93407c23 937d7c27 11000421 (f86378a3)\n[  285.473422] ---[ end trace 0000000000000000 ]---\n\nIt reproduced simply with below script:\nwhile [ 1 ]\ndo\n/exportfs -r\ndone &\n\nwhile [ 1 ]\ndo\ninsmod /nfsd.ko\nmount -t nfsd none /proc/fs/nfsd\numount /proc/fs/nfsd\nrmmod nfsd\ndone &\n\nSo exporting interfaces to user space shall be done at last and\ncleanup at first place.\n\nWith change there is no Kernel OOPs.","modified":"2026-04-01T05:21:44.510276Z","published":"2025-07-04T14:15:32Z","upstream":["CVE-2025-38232"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38232"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"5.15.200.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-70427.json"}}],"schema_version":"1.7.5"}