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| author | peter <peter@FreeBSD.org> | 2005-09-27 18:10:26 +0000 |
|---|---|---|
| committer | peter <peter@FreeBSD.org> | 2005-09-27 18:10:26 +0000 |
| commit | ef35b51d9d50287690c02c0c566d37a0a97161db (patch) | |
| tree | 6cccaad7d1620ad5fe1791733869510c83045c68 /sys | |
| parent | 0d152100b2df7e3e76fc69497ff1287595a74ee4 (diff) | |
| download | FreeBSD-src-ef35b51d9d50287690c02c0c566d37a0a97161db.zip FreeBSD-src-ef35b51d9d50287690c02c0c566d37a0a97161db.tar.gz | |
Don't let the upper bits of %dr6/%dr7 get set.
Submitted by: Nate Eldredge <neldredge@math.ucsd.edu>
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/amd64/amd64/machdep.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c index 3e07952..5345dc1 100644 --- a/sys/amd64/amd64/machdep.c +++ b/sys/amd64/amd64/machdep.c @@ -1726,11 +1726,15 @@ set_dbregs(struct thread *td, struct dbreg *dbregs) * check for undefined settings. Setting these bit patterns * result in undefined behaviour and can lead to an unexpected * TRCTRAP or a general protection fault right here. + * Upper bits of dr6 and dr7 must not be set */ for (i = 0, mask1 = 0x3<<16, mask2 = 0x2<<16; i < 8; i++, mask1 <<= 2, mask2 <<= 2) if ((dbregs->dr[7] & mask1) == mask2) return (EINVAL); + if ((dbregs->dr[6] & 0xffffffff00000000ul) != 0 || + (dbregs->dr[7] & 0xffffffff00000000ul) != 0) + return (EINVAL); pcb = td->td_pcb; |
