Date: Wed, 3 Jun 1998 01:22:50 -0700 (PDT) From: Doug White <dwhite@gdi.uoregon.edu> To: richard@cogsci.ed.ac.uk Cc: freebsd-multimedia@FreeBSD.ORG Subject: Re: fxtv - mmap of driver buffer failed Message-ID: <Pine.BSF.3.96.980603011705.22038b-100000@gdi.uoregon.edu> In-Reply-To: <24168.199806030144@cockburn.cogsci.ed.ac.uk>
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On Wed, 3 Jun 1998 richard@cogsci.ed.ac.uk wrote: > Having not looked at this for a long time, I just installed the 3.0 > SNAP 980520 and the fxtv 0.46 package that comes with it. Unless I > run it as root, I get the message "mmap of driver buffer failed: > Permission denied". What have I missed here? I think this is FXTV falling behind reality. It open /dev/bktr0 read-only but requests read-write protections on the mmap()'d buffer. However this is a security hole since you can still write the device even if you only have read-only perms. It can be overridden by the superuser. See rev 1.75 of src/sys/vm/vm_mmap.c for details. The fix is to have fxtv open /dev/bktr0 O_RDWR and not O_RDONLY. It's too late in the night for me to try this tho. For all I know this was fixed in the fxtv 0.47 which just came out. Doug White | University of Oregon Internet: dwhite@resnet.uoregon.edu | Residence Networking Assistant http://gladstone.uoregon.edu/~dwhite | Computer Science Major To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-multimedia" in the body of the message
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