{"id":"CVE-2023-54316","state":"PUBLISHED","title":"refscale: Fix uninitalized use of wait_queue_head_t","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nrefscale: Fix uninitalized use of wait_queue_head_t\n\nRunning the refscale test occasionally crashes the kernel with the\nfollowing error:\n\n[ 8569.952896] BUG: unable to handle page fault for address: ffffffffffffffe8\n[ 8569.952900] #PF: supervisor read access in kernel mode\n[ 8569.952902] #PF: error_code(0x0000) - not-present page\n[ 8569.952904] PGD c4b048067 P4D c4b049067 PUD c4b04b067 PMD 0\n[ 8569.952910] Oops: 0000 [#1] PREEMPT_RT SMP NOPTI\n[ 8569.952916] Hardware name: Dell Inc. PowerEdge R750/0WMWCR, BIOS 1.2.4 05/28/2021\n[ 8569.952917] RIP: 0010:prepare_to_wait_event+0x101/0x190\n  :\n[ 8569.952940] Call Trace:\n[ 8569.952941]  <TASK>\n[ 8569.952944]  ref_scale_reader+0x380/0x4a0 [refscale]\n[ 8569.952959]  kthread+0x10e/0x130\n[ 8569.952966]  ret_from_fork+0x1f/0x30\n[ 8569.952973]  </TASK>\n\nThe likely cause is that init_waitqueue_head() is called after the call to\nthe torture_create_kthread() function that creates the ref_scale_reader\nkthread.  Although this init_waitqueue_head() call will very likely\ncomplete before this kthread is created and starts running, it is\npossible that the calling kthread will be delayed between the calls to\ntorture_create_kthread() and init_waitqueue_head().  In this case, the\nnew kthread will use the waitqueue head before it is properly initialized,\nwhich is not good for the kernel's health and well-being.\n\nThe above crash happened here:\n\n\tstatic inline void __add_wait_queue(...)\n\t{\n\t\t:\n\t\tif (!(wq->flags & WQ_FLAG_PRIORITY)) <=== Crash here\n\nThe offset of flags from list_head entry in wait_queue_entry is\n-0x18. If reader_tasks[i].wq.head.next is NULL as allocated reader_task\nstructure is zero initialized, the instruction will try to access address\n0xffffffffffffffe8, which is exactly the fault address listed above.\n\nThis commit therefore invokes init_waitqueue_head() before creating\nthe kthread.","publishedAt":"2025-12-30T12:23:46.526Z","updatedAt":"2026-05-11T19:59:36.681Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"066fbd8bc981cf49923bf828b7b4092894df577f","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"ec9d118ad99dc6f1bc674c1e649c25533d89b9ba","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"e0322a255a2242dbe4686b6176b3c83dea490529","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"e5de968a9032366198720eac4f368ed7e690b3ef","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"70a2856fd1d0a040c876ba9e3f89b949ae92e4dd","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"f5063e8948dad7f31adb007284a5d5038ae31bb8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/rcu/refscale.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.195","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.132","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.53","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.4.16","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5.3","status":"unaffected","lessThanOrEqual":"6.5.*","versionType":"semver"},{"version":"6.6","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/rcu/refscale.c"]}],"references":["https://git.kernel.org/stable/c/066fbd8bc981cf49923bf828b7b4092894df577f","https://git.kernel.org/stable/c/ec9d118ad99dc6f1bc674c1e649c25533d89b9ba","https://git.kernel.org/stable/c/e0322a255a2242dbe4686b6176b3c83dea490529","https://git.kernel.org/stable/c/e5de968a9032366198720eac4f368ed7e690b3ef","https://git.kernel.org/stable/c/70a2856fd1d0a040c876ba9e3f89b949ae92e4dd","https://git.kernel.org/stable/c/f5063e8948dad7f31adb007284a5d5038ae31bb8"],"weaknesses":[],"ingestedAt":"2026-10-29T20:06:42.242Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/54xxx/CVE-2023-54316.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-54316","state":"PUBLISHED","datePublished":"2025-12-30T12:23:46.526Z","dateUpdated":"2026-05-11T19:59:36.681Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-12-30T12:06:44.531Z"},"containers":{"cna":{"title":"refscale: Fix uninitalized use of wait_queue_head_t","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nrefscale: Fix uninitalized use of wait_queue_head_t\n\nRunning the refscale test occasionally crashes the kernel with the\nfollowing error:\n\n[ 8569.952896] BUG: unable to handle page fault for address: ffffffffffffffe8\n[ 8569.952900] #PF: supervisor read access in kernel mode\n[ 8569.952902] #PF: error_code(0x0000) - not-present page\n[ 8569.952904] PGD c4b048067 P4D c4b049067 PUD c4b04b067 PMD 0\n[ 8569.952910] Oops: 0000 [#1] PREEMPT_RT SMP NOPTI\n[ 8569.952916] Hardware name: Dell Inc. PowerEdge R750/0WMWCR, BIOS 1.2.4 05/28/2021\n[ 8569.952917] RIP: 0010:prepare_to_wait_event+0x101/0x190\n  :\n[ 8569.952940] Call Trace:\n[ 8569.952941]  <TASK>\n[ 8569.952944]  ref_scale_reader+0x380/0x4a0 [refscale]\n[ 8569.952959]  kthread+0x10e/0x130\n[ 8569.952966]  ret_from_fork+0x1f/0x30\n[ 8569.952973]  </TASK>\n\nThe likely cause is that init_waitqueue_head() is called after the call to\nthe torture_create_kthread() function that creates the ref_scale_reader\nkthread.  Although this init_waitqueue_head() call will very likely\ncomplete before this kthread is created and starts running, it is\npossible that the calling kthread will be delayed between the calls to\ntorture_create_kthread() and init_waitqueue_head().  In this case, the\nnew kthread will use the waitqueue head before it is properly initialized,\nwhich is not good for the kernel's health and well-being.\n\nThe above crash happened here:\n\n\tstatic inline void __add_wait_queue(...)\n\t{\n\t\t:\n\t\tif (!(wq->flags & WQ_FLAG_PRIORITY)) <=== Crash here\n\nThe offset of flags from list_head entry in wait_queue_entry is\n-0x18. If reader_tasks[i].wq.head.next is NULL as allocated reader_task\nstructure is zero initialized, the instruction will try to access address\n0xffffffffffffffe8, which is exactly the fault address listed above.\n\nThis commit therefore invokes init_waitqueue_head() before creating\nthe kthread."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"066fbd8bc981cf49923bf828b7b4092894df577f","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"ec9d118ad99dc6f1bc674c1e649c25533d89b9ba","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"e0322a255a2242dbe4686b6176b3c83dea490529","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"e5de968a9032366198720eac4f368ed7e690b3ef","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"70a2856fd1d0a040c876ba9e3f89b949ae92e4dd","versionType":"git"},{"version":"653ed64b01dc5989f8f579d0038e987476c2c023","status":"affected","lessThan":"f5063e8948dad7f31adb007284a5d5038ae31bb8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/rcu/refscale.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.195","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.132","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.53","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.4.16","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5.3","status":"unaffected","lessThanOrEqual":"6.5.*","versionType":"semver"},{"version":"6.6","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/rcu/refscale.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/066fbd8bc981cf49923bf828b7b4092894df577f"},{"url":"https://git.kernel.org/stable/c/ec9d118ad99dc6f1bc674c1e649c25533d89b9ba"},{"url":"https://git.kernel.org/stable/c/e0322a255a2242dbe4686b6176b3c83dea490529"},{"url":"https://git.kernel.org/stable/c/e5de968a9032366198720eac4f368ed7e690b3ef"},{"url":"https://git.kernel.org/stable/c/70a2856fd1d0a040c876ba9e3f89b949ae92e4dd"},{"url":"https://git.kernel.org/stable/c/f5063e8948dad7f31adb007284a5d5038ae31bb8"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T19:59:36.681Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.10.195"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.15.132"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.1.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.4.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.5.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.6"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}