Description
In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix possible memleak when register 'hctx' failed There's issue as follows when do fault injection test: unreferenced object 0xffff888132a9f400 (size 512): comm "insmod", pid 308021, jiffies 4324277909 (age 509.733s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 08 f4 a9 32 81 88 ff ff ...........2.... 08 f4 a9 32 81 88 ff ff 00 00 00 00 00 00 00 00 ...2............ backtrace: [<00000000e8952bb4>] kmalloc_node_trace+0x22/0xa0 [<00000000f9980e0f>] blk_mq_alloc_and_init_hctx+0x3f1/0x7e0 [<000000002e719efa>] blk_mq_realloc_hw_ctxs+0x1e6/0x230 [<000000004f1fda40>] blk_mq_init_allocated_queue+0x27e/0x910 [<00000000287123ec>] __blk_mq_alloc_disk+0x67/0xf0 [<00000000a2a34657>] 0xffffffffa2ad310f [<00000000b173f718>] 0xffffffffa2af824a [<0000000095a1dabb>] do_one_initcall+0x87/0x2a0 [<00000000f32fdf93>] do_init_module+0xdf/0x320 [<00000000cbe8541e>] load_module+0x3006/0x3390 [<0000000069ed1bdb>] __do_sys_finit_module+0x113/0x1b0 [<00000000a1a29ae8>] do_syscall_64+0x35/0x80 [<000000009cd878b0>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 Fault injection context as follows: kobject_add blk_mq_register_hctx blk_mq_sysfs_register blk_register_queue device_add_disk null_add_dev.part.0 [null_blk] As 'blk_mq_register_hctx' may already add some objects when failed halfway, but there isn't do fallback, caller don't know which objects add failed. To solve above issue just do fallback when add objects failed halfway in 'blk_mq_register_hctx'.
Affected products
linux: linux kernel
References9
- git.kernel.org/stable/c/02bc8bc6eab03c84373281b85cb6e98747172ff7 Patch
- git.kernel.org/stable/c/33e8a3f61814ea30615d0fafaf50477975d6c1ca Patch
- git.kernel.org/stable/c/4b7a21c57b14fbcd0e1729150189e5933f5088e9 Patch
- git.kernel.org/stable/c/4b7fafa5f39b15c3a6ca3b95e534d05d6904cc95 Patch
- git.kernel.org/stable/c/654870789c3c1b9763316ef1c71d7a449127b175 Patch
- git.kernel.org/stable/c/87fd18016a47ea8ae12641377a390172c4aa97a7 Patch
- git.kernel.org/stable/c/cb186eb47fb9dd327bdefa15f0c5fc55c53a40dd Patch
- git.kernel.org/stable/c/e8022da1fa2fdf2fa204b445dd3354e7a66d085a Patch
- git.kernel.org/stable/c/eff45bfbc25a2509a6362dea6e699e14083c693c Patch
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 8 · as of 9 November 2026
- CWE
- CWE-401
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