cbcvebase.
CVE-2025-21886
published 2025-03-27

CVE-2025-21886: In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix implicit ODP hang on parent deregistration Fix the…

PriorityP418medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.19%
9.0th percentile
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix implicit ODP hang on parent deregistration Fix the destroy_unused_implicit_child_mr() to prevent hanging during parent deregistration as of below [1]. Upon entering destroy_unused_implicit_child_mr(), the reference count for the implicit MR parent is incremented using: refcount_inc_not_zero(). A corresponding decrement must be performed if free_implicit_child_mr_work() is not called. The code has been updated to properly manage the reference count that was incremented. [1] INFO: task python3:2157 blocked for more than 120 seconds. Not tainted 6.12.0-rc7+ #1633 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:python3 state:D stack:0 pid:2157 tgid:2157 ppid:1685 flags:0x00000000 Call Trace: __schedule+0x420/0xd30 schedule+0x47/0x130 __mlx5_ib_dereg_mr+0x379/0x5d0 [mlx5_ib] ? __pfx_autoremove_wake_function+0x10/0x10 ib_dereg_mr_user+0x5f/0x120 [ib_core] ? lock_release+0xc6/0x280 destroy_hw_idr_uobject+0x1d/0x60 [ib_uverbs] uverbs_destroy_uobject+0x58/0x1d0 [ib_uverbs] uobj_destroy+0x3f/0x70 [ib_uverbs] ib_uverbs_cmd_verbs+0x3e4/0xbb0 [ib_uverbs] ? __pfx_uverbs_destroy_def_handler+0x10/0x10 [ib_uverbs] ? lock_acquire+0xc1/0x2f0 ? ib_uverbs_ioctl+0xcb/0x170 [ib_uverbs] ? ib_uverbs_ioctl+0x116/0x170 [ib_uverbs] ? lock_release+0xc6/0x280 ib_uverbs_ioctl+0xe7/0x170 [ib_uverbs] ? ib_uverbs_ioctl+0xcb/0x170 [ib_uverbs] __x64_sys_ioctl+0x1b0/0xa70 ? kmem_cache_free+0x221/0x400 do_syscall_64+0x6b/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f20f21f017b RSP: 002b:00007ffcfc4a77c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffcfc4a78d8 RCX: 00007f20f21f017b RDX: 00007ffcfc4a78c0 RSI: 00000000c0181b01 RDI: 0000000000000003 RBP: 00007ffcfc4a78a0 R08: 000056147d125190 R09: 00007f20f1f14c60 R10: 0000000000000001 R11: 0000000000000246 R12: 00007ffcfc4a7890 R13: 000000000000001c R14: 000056147d100fc0 R15: 00007f20e365c9d0

Affected

15 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.19-1 (forky)linux 6.12.19-1 (forky)
linuxlinux>= 6.12.13 < 6.12.186.12.18
linuxlinux>= 6.13.2 < 6.13.66.13.6
linuxlinux>= 7cc8f681f6d4ae4478ae0f60485fc768f2b450da < cb96ae783e7249e8e5a50c22952c0bb2983133dfcb96ae783e7249e8e5a50c22952c0bb2983133df
linuxlinux>= d3d930411ce390e532470194296658a960887773 < 3d8c6f26893d55fab218ad086719de1fc9bb86ba3d8c6f26893d55fab218ad086719de1fc9bb86ba
linuxlinux>= edfb65dbb9ffd3102f3ff4dd21316158e56f1976 < a095ede2daca49d15e74d66d014883f2fa8bb924a095ede2daca49d15e74d66d014883f2fa8bb924
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 6.12.13 < 6.12.186.12.18
linuxlinux_kernel>= 6.13.2 < 6.13.66.13.6
msrccbl2_xorg-x11-server_1.20.10-12_on_cbl_mariner_2.0
msrccbl2_xorg-x11-server_1.20.10-15_on_cbl_mariner_2.0
msrccbl_mariner_2.0_arm
msrccbl_mariner_2.0_x64

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_msrc7.8HIGH
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
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