oss-sec mailing list archives
Re: CVE request: kernel: sys_semctl: fix kernel stack leakage
From: Eugene Teo <eugene () redhat com>
Date: Thu, 04 Nov 2010 15:27:59 +0800
On 11/04/2010 02:40 PM, Eugene Teo wrote:
"The semctl syscall has several code paths that lead to the leakage of uninitialized kernel stack memory (namely the IPC_INFO, SEM_INFO, IPC_STAT, and SEM_STAT commands) during the use of the older, obsolete version of the semid_ds struct. The copy_semid_to_user() function declares a semid_ds struct on the stack and copies it back to the user without initializing or zeroing the "sem_base", "sem_pending", "sem_pending_last", and "undo" pointers, allowing the leakage of 16 bytes of kernel stack memory. The code is still reachable on 32-bit systems - when calling semctl() newer glibc's automatically OR the IPC command with the IPC_64 flag, but invoking the syscall directly allows users to use the older versions of the struct." Upstream commit: http://git.kernel.org/linus/982f7c2b2e6a28f8f266e075d92e19c0dd4c6e56 Credit: Dan Rosenberg Reference: https://bugzilla.redhat.com/show_bug.cgi?id=649614
Whoops, this has been assigned CVE-2010-4083. Thanks, Eugene -- main(i) { putchar(182623909 >> (i-1) * 5&31|!!(i<7)<<6) && main(++i); }
Current thread:
- CVE request: kernel: sys_semctl: fix kernel stack leakage Eugene Teo (Nov 03)
- Re: CVE request: kernel: sys_semctl: fix kernel stack leakage Eugene Teo (Nov 04)