Message ID | 20190802171128.10484-1-connor.kuehl@canonical.com |
---|---|
State | New |
Headers | show |
Series | [SRU,Xenial,CVE-2018-20856] block: blk_init_allocated_queue() set q->fq as NULL in the fail case | expand |
On 2019-08-02 10:11:28, Connor Kuehl wrote: > From: xiao jin <jin.xiao@intel.com> > > CVE-2018-20856 > > We find the memory use-after-free issue in __blk_drain_queue() > on the kernel 4.14. After read the latest kernel 4.18-rc6 we > think it has the same problem. > > Memory is allocated for q->fq in the blk_init_allocated_queue(). > If the elevator init function called with error return, it will > run into the fail case to free the q->fq. > > Then the __blk_drain_queue() uses the same memory after the free > of the q->fq, it will lead to the unpredictable event. > > The patch is to set q->fq as NULL in the fail case of > blk_init_allocated_queue(). > > Fixes: commit 7c94e1c157a2 ("block: introduce blk_flush_queue to drive flush machinery") > Cc: <stable@vger.kernel.org> > Reviewed-by: Ming Lei <ming.lei@redhat.com> > Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> > Signed-off-by: xiao jin <jin.xiao@intel.com> > Signed-off-by: Jens Axboe <axboe@kernel.dk> > (backported from commit 54648cf1ec2d7f4b6a71767799c45676a138ca24) > [ Connor Kuehl: had to place the line from the patch in manually since > the patch context disagreed with what the routine looks like now > (different label, different return statement). Barely more involved > than an offset adjustment. ] > Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com> Acked-by: Tyler Hicks <tyhicks@canonical.com> Thanks! Tyler > --- > block/blk-core.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/blk-core.c b/block/blk-core.c > index f83b9c2b6a14..a3e1f4fcb2e5 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -861,6 +861,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, > > fail: > blk_free_flush_queue(q->fq); > + q->fq = NULL; > return NULL; > } > EXPORT_SYMBOL(blk_init_allocated_queue); > -- > 2.20.1 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
On 2019-08-02 10:11:28 , Connor Kuehl wrote: > From: xiao jin <jin.xiao@intel.com> > > CVE-2018-20856 > > We find the memory use-after-free issue in __blk_drain_queue() > on the kernel 4.14. After read the latest kernel 4.18-rc6 we > think it has the same problem. > > Memory is allocated for q->fq in the blk_init_allocated_queue(). > If the elevator init function called with error return, it will > run into the fail case to free the q->fq. > > Then the __blk_drain_queue() uses the same memory after the free > of the q->fq, it will lead to the unpredictable event. > > The patch is to set q->fq as NULL in the fail case of > blk_init_allocated_queue(). > > Fixes: commit 7c94e1c157a2 ("block: introduce blk_flush_queue to drive flush machinery") > Cc: <stable@vger.kernel.org> > Reviewed-by: Ming Lei <ming.lei@redhat.com> > Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> > Signed-off-by: xiao jin <jin.xiao@intel.com> > Signed-off-by: Jens Axboe <axboe@kernel.dk> > (backported from commit 54648cf1ec2d7f4b6a71767799c45676a138ca24) > [ Connor Kuehl: had to place the line from the patch in manually since > the patch context disagreed with what the routine looks like now > (different label, different return statement). Barely more involved > than an offset adjustment. ] > Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com> > --- > block/blk-core.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/blk-core.c b/block/blk-core.c > index f83b9c2b6a14..a3e1f4fcb2e5 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -861,6 +861,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, > > fail: > blk_free_flush_queue(q->fq); > + q->fq = NULL; > return NULL; > } > EXPORT_SYMBOL(blk_init_allocated_queue); > -- > 2.20.1 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
On 2019-08-02 10:11:28 , Connor Kuehl wrote: > From: xiao jin <jin.xiao@intel.com> > > CVE-2018-20856 > > We find the memory use-after-free issue in __blk_drain_queue() > on the kernel 4.14. After read the latest kernel 4.18-rc6 we > think it has the same problem. > > Memory is allocated for q->fq in the blk_init_allocated_queue(). > If the elevator init function called with error return, it will > run into the fail case to free the q->fq. > > Then the __blk_drain_queue() uses the same memory after the free > of the q->fq, it will lead to the unpredictable event. > > The patch is to set q->fq as NULL in the fail case of > blk_init_allocated_queue(). > > Fixes: commit 7c94e1c157a2 ("block: introduce blk_flush_queue to drive flush machinery") > Cc: <stable@vger.kernel.org> > Reviewed-by: Ming Lei <ming.lei@redhat.com> > Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> > Signed-off-by: xiao jin <jin.xiao@intel.com> > Signed-off-by: Jens Axboe <axboe@kernel.dk> > (backported from commit 54648cf1ec2d7f4b6a71767799c45676a138ca24) > [ Connor Kuehl: had to place the line from the patch in manually since > the patch context disagreed with what the routine looks like now > (different label, different return statement). Barely more involved > than an offset adjustment. ] > Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com> > --- > block/blk-core.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/blk-core.c b/block/blk-core.c > index f83b9c2b6a14..a3e1f4fcb2e5 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -861,6 +861,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, > > fail: > blk_free_flush_queue(q->fq); > + q->fq = NULL; > return NULL; > } > EXPORT_SYMBOL(blk_init_allocated_queue); > -- > 2.20.1 > > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
diff --git a/block/blk-core.c b/block/blk-core.c index f83b9c2b6a14..a3e1f4fcb2e5 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -861,6 +861,7 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, fail: blk_free_flush_queue(q->fq); + q->fq = NULL; return NULL; } EXPORT_SYMBOL(blk_init_allocated_queue);