Re: WARNING in kmalloc_slab (3)

2018-02-06 Thread Dmitry Vyukov
On Tue, Dec 12, 2017 at 10:22 PM, Eric Biggers wrote: > On Mon, Dec 04, 2017 at 12:26:32PM +0300, Dan Carpenter wrote: >> On Mon, Dec 04, 2017 at 09:18:05AM +0100, Dmitry Vyukov wrote: >> > On Mon, Dec 4, 2017 at 9:14 AM, Dan Carpenter >> > wrote: >> > > On Sun, Dec 03, 2017 at 12:16:08PM -0800,

Re: WARNING in kmalloc_slab (3)

2017-12-12 Thread Eric Biggers
On Mon, Dec 04, 2017 at 12:26:32PM +0300, Dan Carpenter wrote: > On Mon, Dec 04, 2017 at 09:18:05AM +0100, Dmitry Vyukov wrote: > > On Mon, Dec 4, 2017 at 9:14 AM, Dan Carpenter > > wrote: > > > On Sun, Dec 03, 2017 at 12:16:08PM -0800, Eric Biggers wrote: > > >> Looks like BLKTRACESETUP doesn't

Re: WARNING in kmalloc_slab (3)

2017-12-12 Thread Dmitry Vyukov
On Mon, Dec 4, 2017 at 10:26 AM, Dan Carpenter wrote: > On Mon, Dec 04, 2017 at 09:18:05AM +0100, Dmitry Vyukov wrote: >> On Mon, Dec 4, 2017 at 9:14 AM, Dan Carpenter >> wrote: >> > On Sun, Dec 03, 2017 at 12:16:08PM -0800, Eric Biggers wrote: >> >> Looks like BLKTRACESETUP doesn't limit the '.

Re: WARNING in kmalloc_slab (3)

2017-12-04 Thread Dan Carpenter
On Sun, Dec 03, 2017 at 12:16:08PM -0800, Eric Biggers wrote: > Looks like BLKTRACESETUP doesn't limit the '.buf_nr' parameter, allowing > anyone > who can open a block device to cause an extremely large kmalloc. Here's a > simplified reproducer: > There are lots of places which allow people to

Re: WARNING in kmalloc_slab (3)

2017-12-04 Thread Dan Carpenter
On Mon, Dec 04, 2017 at 09:18:05AM +0100, Dmitry Vyukov wrote: > On Mon, Dec 4, 2017 at 9:14 AM, Dan Carpenter > wrote: > > On Sun, Dec 03, 2017 at 12:16:08PM -0800, Eric Biggers wrote: > >> Looks like BLKTRACESETUP doesn't limit the '.buf_nr' parameter, allowing > >> anyone > >> who can open a

Re: WARNING in kmalloc_slab (3)

2017-12-04 Thread Dmitry Vyukov
On Mon, Dec 4, 2017 at 9:14 AM, Dan Carpenter wrote: > On Sun, Dec 03, 2017 at 12:16:08PM -0800, Eric Biggers wrote: >> Looks like BLKTRACESETUP doesn't limit the '.buf_nr' parameter, allowing >> anyone >> who can open a block device to cause an extremely large kmalloc. Here's a >> simplified re

Re: WARNING in kmalloc_slab (3)

2017-12-03 Thread Eric Biggers
+Cc linux-block On Sun, Dec 03, 2017 at 06:25:01AM -0800, syzbot wrote: > WARNING: CPU: 0 PID: 3081 at mm/slab_common.c:971 kmalloc_slab+0x5d/0x70 > mm/slab_common.c:971 > Kernel panic - not syncing: panic_on_warn set ... > [...] > __do_kmalloc mm/slab.c:3706 [inline] > __kmalloc+0x25/0x760 mm/