On Tuesday, January 20, 2015 10:48:58 PM Sasha Levin wrote:
On 01/19/2015 03:08 PM, Paul Moore wrote:
> There are several areas in the kernel that create temporary filename
>
> objects using the following pattern:
> int func(const char *name)
> {
>
> struct filename *file = { .name = name };
> ...
> return 0;
>
> }
>
> ... which for the most part works okay, but it causes havoc within the
> audit subsystem as the filename object does not persist beyond the
> lifetime of the function. This patch converts all of these temporary
> filename objects into proper filename objects using getname_kernel()
> and putname() which ensure that the filename object persists until the
> audit subsystem is finished with it.
Hi Paul,
With this patch (bisected) my vm fails to boot with a virtio-9p rootfs:
[ 27.313687] fa00 2097152 vda driver: virtio_blk
[ 27.314218] 103:00000 8192 sda driver: sd
[ 27.314714] DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify explicit
textual name for "root=" boot option. [ 27.315963] Kernel panic - not
syncing: VFS: Unable to mount root fs on unknown-block(0,0) [ 27.316885]
CPU: 29 PID: 1 Comm: swapper/0 Not tainted
3.19.0-rc5-next-20150120-sasha-00053-gb2e3c55-dirty #1772 [ 27.316885]
ffffffffffffffff ffff88005cb8bd28 ffffffffb14522b5 000000000000004e [
27.316885] ffffffffb26d4950 ffff88005cb8bda8 ffffffffb144c298
ffff88005cb8bd48 [ 27.316885] ffffffff00000010 ffff88005cb8bdb8
ffff88005cb8bd58 fffffffffffffffe [ 27.316885] Call Trace:
[ 27.316885] [<ffffffffb14522b5>] dump_stack+0x4f/0x7b
[ 27.316885] [<ffffffffb144c298>] panic+0xd2/0x216
[ 27.316885] [<ffffffffb431558b>] mount_block_root+0x18b/0x244
[ 27.316885] [<ffffffffb43158ae>] mount_root+0x128/0x133
[ 27.316885] [<ffffffffb4315a1b>] prepare_namespace+0x162/0x19b
[ 27.316885] [<ffffffffb4315223>] kernel_init_freeable+0x285/0x29a
[ 27.316885] [<ffffffffb14472b0>] ? rest_init+0xd0/0xd0
[ 27.316885] [<ffffffffb14472be>] kernel_init+0xe/0xf0
[ 27.316885] [<ffffffffb148007c>] ret_from_fork+0x7c/0xb0
[ 27.316885] [<ffffffffb14472b0>] ? rest_init+0xd0/0xd0
[ 27.316885] Dumping ftrace buffer:
[ 27.316885] (ftrace buffer empty)
[ 27.316885] Kernel Offset: 0x2d000000 from 0xffffffff81000000 (relocation
range: 0xffffffff80000000-0xffffffffbfffffff) [ 27.316885] Rebooting in 1
seconds..
virtio-9p is not even listed as an option now.
Thanks for reporting the problem, we're currently working on a fix:
*
https://lkml.org/lkml/2015/1/20/710
--
paul moore
security @ redhat