ghsa-6r3f-6qj7-7p6v
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix potential deadlock when reconnecting channels
Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order and prevent the following deadlock from happening
====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc3-build2+ #1301 Tainted: G S W
cifsd/6055 is trying to acquire lock: ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200
but task is already holding lock: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}: validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_setup_session+0x81/0x4b0 cifs_get_smb_ses+0x771/0x900 cifs_mount_get_session+0x7e/0x170 cifs_mount+0x92/0x2d0 cifs_smb3_do_mount+0x161/0x460 smb3_get_tree+0x55/0x90 vfs_get_tree+0x46/0x180 do_new_mount+0x1b0/0x2e0 path_mount+0x6ee/0x740 do_mount+0x98/0xe0 __do_sys_mount+0x148/0x180 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (&ret_buf->ses_lock){+.+.}-{3:3}: validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_match_super+0x101/0x320 sget+0xab/0x270 cifs_smb3_do_mount+0x1e0/0x460 smb3_get_tree+0x55/0x90 vfs_get_tree+0x46/0x180 do_new_mount+0x1b0/0x2e0 path_mount+0x6ee/0x740 do_mount+0x98/0xe0 __do_sys_mount+0x148/0x180 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}: check_noncircular+0x95/0xc0 check_prev_add+0x115/0x2f0 validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_signal_cifsd_for_reconnect+0x134/0x200 __cifs_reconnect+0x8f/0x500 cifs_handle_standard+0x112/0x280 cifs_demultiplex_thread+0x64d/0xbc0 kthread+0x2f7/0x310 ret_from_fork+0x2a/0x230 ret_from_fork_asm+0x1a/0x30
other info that might help us debug this:
Chain exists of: &tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ret_buf->chan_lock); lock(&ret_buf->ses_lock); lock(&ret_buf->chan_lock); lock(&tcp_ses->srv_lock);
*** DEADLOCK ***
3 locks held by cifsd/6055: #0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200 #1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200 #2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200
{ "affected": [], "aliases": [ "CVE-2025-38244" ], "database_specific": { "cwe_ids": [], "github_reviewed": false, "github_reviewed_at": null, "nvd_published_at": "2025-07-09T11:15:26Z", "severity": null }, "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix potential deadlock when reconnecting channels\n\nFix cifs_signal_cifsd_for_reconnect() to take the correct lock order\nand prevent the following deadlock from happening\n\n======================================================\nWARNING: possible circular locking dependency detected\n6.16.0-rc3-build2+ #1301 Tainted: G S W\n------------------------------------------------------\ncifsd/6055 is trying to acquire lock:\nffff88810ad56038 (\u0026tcp_ses-\u003esrv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200\n\nbut task is already holding lock:\nffff888119c64330 (\u0026ret_buf-\u003echan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200\n\nwhich lock already depends on the new lock.\n\nthe existing dependency chain (in reverse order) is:\n\n-\u003e #2 (\u0026ret_buf-\u003echan_lock){+.+.}-{3:3}:\n validate_chain+0x1cf/0x270\n __lock_acquire+0x60e/0x780\n lock_acquire.part.0+0xb4/0x1f0\n _raw_spin_lock+0x2f/0x40\n cifs_setup_session+0x81/0x4b0\n cifs_get_smb_ses+0x771/0x900\n cifs_mount_get_session+0x7e/0x170\n cifs_mount+0x92/0x2d0\n cifs_smb3_do_mount+0x161/0x460\n smb3_get_tree+0x55/0x90\n vfs_get_tree+0x46/0x180\n do_new_mount+0x1b0/0x2e0\n path_mount+0x6ee/0x740\n do_mount+0x98/0xe0\n __do_sys_mount+0x148/0x180\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\n-\u003e #1 (\u0026ret_buf-\u003eses_lock){+.+.}-{3:3}:\n validate_chain+0x1cf/0x270\n __lock_acquire+0x60e/0x780\n lock_acquire.part.0+0xb4/0x1f0\n _raw_spin_lock+0x2f/0x40\n cifs_match_super+0x101/0x320\n sget+0xab/0x270\n cifs_smb3_do_mount+0x1e0/0x460\n smb3_get_tree+0x55/0x90\n vfs_get_tree+0x46/0x180\n do_new_mount+0x1b0/0x2e0\n path_mount+0x6ee/0x740\n do_mount+0x98/0xe0\n __do_sys_mount+0x148/0x180\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\n-\u003e #0 (\u0026tcp_ses-\u003esrv_lock){+.+.}-{3:3}:\n check_noncircular+0x95/0xc0\n check_prev_add+0x115/0x2f0\n validate_chain+0x1cf/0x270\n __lock_acquire+0x60e/0x780\n lock_acquire.part.0+0xb4/0x1f0\n _raw_spin_lock+0x2f/0x40\n cifs_signal_cifsd_for_reconnect+0x134/0x200\n __cifs_reconnect+0x8f/0x500\n cifs_handle_standard+0x112/0x280\n cifs_demultiplex_thread+0x64d/0xbc0\n kthread+0x2f7/0x310\n ret_from_fork+0x2a/0x230\n ret_from_fork_asm+0x1a/0x30\n\nother info that might help us debug this:\n\nChain exists of:\n \u0026tcp_ses-\u003esrv_lock --\u003e \u0026ret_buf-\u003eses_lock --\u003e \u0026ret_buf-\u003echan_lock\n\n Possible unsafe locking scenario:\n\n CPU0 CPU1\n ---- ----\n lock(\u0026ret_buf-\u003echan_lock);\n lock(\u0026ret_buf-\u003eses_lock);\n lock(\u0026ret_buf-\u003echan_lock);\n lock(\u0026tcp_ses-\u003esrv_lock);\n\n *** DEADLOCK ***\n\n3 locks held by cifsd/6055:\n #0: ffffffff857de398 (\u0026cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200\n #1: ffff888119c64060 (\u0026ret_buf-\u003eses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200\n #2: ffff888119c64330 (\u0026ret_buf-\u003echan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200", "id": "GHSA-6r3f-6qj7-7p6v", "modified": "2025-07-09T12:31:34Z", "published": "2025-07-09T12:31:34Z", "references": [ { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-38244" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/711741f94ac3cf9f4e3aa73aa171e76d188c0819" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/7f3ead8ebc0ef65b6c89a13912b4e80218425629" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/c82c7041258d96e3286f6790ab700e4edd3cc9e3" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/fe035dc78aa6ca8f862857d45beaf7a0e03206ca" } ], "schema_version": "1.4.0", "severity": [] }
Sightings
Author | Source | Type | Date |
---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.