{"id":"CVE-2026-74734","summary":"firewire: ohci: fix NULL pointer dereference in ar_context_release","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfirewire: ohci: fix NULL pointer dereference in ar_context_release\n\nDuring the error handling path of the driver's probe function, a NULL\npointer dereference can occur in ar_context_release().\n\nWhen pci_probe() fails early (e.g., if pcim_enable_device() or MMIO mapping\nfails), the devres cleanup mechanism invokes release_ohci(). This function\nunconditionally calls ar_context_release() to clean up the asynchronous\nreceive contexts. However, if ar_context_init() was not yet called,\nctx-\u003eohci remains NULL (as the fw_ohci structure is zero-initialized by\ndevres_alloc()).\n\nar_context_release() immediately dereferences ctx-\u003eohci to get the dev\npointer before checking if the context was actually initialized, leading to\na crash:\n\nOops: general protection fault, probably for non-canonical address\n0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]\nRIP: 0010:ar_context_release+0x3f/0x380 drivers/firewire/ohci.c:543\nCall Trace:\n release_ohci+0x3f/0x60 drivers/firewire/ohci.c:3567\n release_nodes drivers/base/devres.c:546 [inline]\n devres_release_all+0x1a8/0x260 drivers/base/devres.c:576\n device_unbind_cleanup drivers/base/dd.c:597 [inline]\n really_probe+0x451/0xae0 drivers/base/dd.c:772\n\nTo fix this, move the assignment of the dev pointer after the !ctx-\u003ebuffer\ncheck. If ctx-\u003ebuffer is NULL, it indicates that the context was never\nsuccessfully initialized and there is nothing to release, safely avoiding\nthe dereference of the uninitialized ctx-\u003eohci pointer.","modified":"2026-08-28T11:48:23.516425591Z","published":"2026-08-26T14:36:48.753Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74734.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/42d217add8d80d6e7d9f58f80d11ea9b07ea113e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7d228ba43279de2d191f25e139fad166409c2c06"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ed5470771c7ed7f959230c4697f316af83426a90"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74734.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74734"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5716e58aecdd4f7225c2e46ce903a839fc54f22f"},{"fixed":"ed5470771c7ed7f959230c4697f316af83426a90"},{"fixed":"7d228ba43279de2d191f25e139fad166409c2c06"},{"fixed":"42d217add8d80d6e7d9f58f80d11ea9b07ea113e"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74734.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.5.0"},{"fixed":"6.18.46"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74734.json"}}],"schema_version":"1.9.0"}