{"id":"CVE-2025-38682","state":"PUBLISHED","title":"i2c: core: Fix double-free of fwnode in i2c_unregister_device()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: core: Fix double-free of fwnode in i2c_unregister_device()\n\nBefore commit df6d7277e552 (\"i2c: core: Do not dereference fwnode in struct\ndevice\"), i2c_unregister_device() only called fwnode_handle_put() on\nof_node-s in the form of calling of_node_put(client->dev.of_node).\n\nBut after this commit the i2c_client's fwnode now unconditionally gets\nfwnode_handle_put() on it.\n\nWhen the i2c_client has no primary (ACPI / OF) fwnode but it does have\na software fwnode, the software-node will be the primary node and\nfwnode_handle_put() will put() it.\n\nBut for the software fwnode device_remove_software_node() will also put()\nit leading to a double free:\n\n[   82.665598] ------------[ cut here ]------------\n[   82.665609] refcount_t: underflow; use-after-free.\n[   82.665808] WARNING: CPU: 3 PID: 1502 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x11\n...\n[   82.666830] RIP: 0010:refcount_warn_saturate+0xba/0x110\n...\n[   82.666962]  <TASK>\n[   82.666971]  i2c_unregister_device+0x60/0x90\n\nFix this by not calling fwnode_handle_put() when the primary fwnode is\na software-node.","publishedAt":"2025-09-04T15:32:37.403Z","updatedAt":"2026-05-11T21:32:56.493Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"df6d7277e5525d6cce63127dd93ebec4c6354fa0","status":"affected","lessThan":"ffe02f7c4e36090154646612e67d331832f92037","versionType":"git"},{"version":"df6d7277e5525d6cce63127dd93ebec4c6354fa0","status":"affected","lessThan":"1c24e5fc0c7096e00c202a6a3e0c342c1afb47c2","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.16.2","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]}],"references":["https://git.kernel.org/stable/c/ffe02f7c4e36090154646612e67d331832f92037","https://git.kernel.org/stable/c/1c24e5fc0c7096e00c202a6a3e0c342c1afb47c2"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/38xxx/CVE-2025-38682.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38682","state":"PUBLISHED","datePublished":"2025-09-04T15:32:37.403Z","dateUpdated":"2026-05-11T21:32:56.493Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T04:51:24.031Z"},"containers":{"cna":{"title":"i2c: core: Fix double-free of fwnode in i2c_unregister_device()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: core: Fix double-free of fwnode in i2c_unregister_device()\n\nBefore commit df6d7277e552 (\"i2c: core: Do not dereference fwnode in struct\ndevice\"), i2c_unregister_device() only called fwnode_handle_put() on\nof_node-s in the form of calling of_node_put(client->dev.of_node).\n\nBut after this commit the i2c_client's fwnode now unconditionally gets\nfwnode_handle_put() on it.\n\nWhen the i2c_client has no primary (ACPI / OF) fwnode but it does have\na software fwnode, the software-node will be the primary node and\nfwnode_handle_put() will put() it.\n\nBut for the software fwnode device_remove_software_node() will also put()\nit leading to a double free:\n\n[   82.665598] ------------[ cut here ]------------\n[   82.665609] refcount_t: underflow; use-after-free.\n[   82.665808] WARNING: CPU: 3 PID: 1502 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x11\n...\n[   82.666830] RIP: 0010:refcount_warn_saturate+0xba/0x110\n...\n[   82.666962]  <TASK>\n[   82.666971]  i2c_unregister_device+0x60/0x90\n\nFix this by not calling fwnode_handle_put() when the primary fwnode is\na software-node."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"df6d7277e5525d6cce63127dd93ebec4c6354fa0","status":"affected","lessThan":"ffe02f7c4e36090154646612e67d331832f92037","versionType":"git"},{"version":"df6d7277e5525d6cce63127dd93ebec4c6354fa0","status":"affected","lessThan":"1c24e5fc0c7096e00c202a6a3e0c342c1afb47c2","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.16.2","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/i2c/i2c-core-base.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ffe02f7c4e36090154646612e67d331832f92037"},{"url":"https://git.kernel.org/stable/c/1c24e5fc0c7096e00c202a6a3e0c342c1afb47c2"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:32:56.493Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.16.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.17"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}