From: Saubhik Mukherjee <email@example.com> To: firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org Cc: email@example.com, firstname.lastname@example.org, email@example.com Subject: [question] potential race between capinc_tty_init & capi_release Date: Tue, 17 Aug 2021 14:43:22 +0530 [thread overview] Message-ID: <firstname.lastname@example.org> (raw) In drivers/isdn/capi/capi.c, based on the output of a static analysis tool, we found the possibility of the following race condition: In capi_init, register_chrdev registers file operations callbacks, capi_fops. Then capinc_tty_init is executed. Simultaneously the following chain of calls can occur (after a successful capi_open call). capi_release -> capincci_free -> capincci_free_minor -> capiminor_free -> tty_unregister_device tty_unregister_device reads capinc_tty_driver, which might not have been initialized at this point. So, we have a race between capi_release and capinc_tty_init. If this is a possible race scenario, maybe moving register_chrdev after capinc_tty_init could fix it. But I am not sure if this will break something else. Please let me know if this is a potential race and can be fixed as mentioned. Since this is based on a static analysis tool, this is not tested.
next reply other threads:[~2021-08-17 9:13 UTC|newest] Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-08-17 9:13 Saubhik Mukherjee [this message] 2021-08-17 16:28 ` Greg KH
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