Re: [PATCH -next] exec: Fix mem leak in kernel_read_file

[gregkh@xxxxxxxxxxxxxxxxxxx]

On Wed, Mar 13, 2019 at 02:12:30PM +0000, Dmitry Kasatkin wrote:
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> From: Sasha Levin <sashal@xxxxxxxxxx>
> Sent: Tuesday, March 12, 2019 1:16 AM
> To: Dmitry Kasatkin
> Cc: Al Viro; yuehaibing; linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; keescook@xxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx; gregkh@xxxxxxxxxx
> Subject: Re: [PATCH -next] exec: Fix mem leak in kernel_read_file
>     
> On Mon, Mar 11, 2019 at 04:59:14PM +0000, Dmitry Kasatkin wrote:
> >
> >From: Al Viro <viro@xxxxxxxxxxxxxxxx> on behalf of Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> >Sent: Tuesday, February 19, 2019 4:25 AM
> >To: yuehaibing
> >Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; Dmitry Kasatkin; keescook@xxxxxxxxxxxx
> >Subject: Re: [PATCH -next] exec: Fix mem leak in kernel_read_file
> > 
> >On Tue, Feb 19, 2019 at 10:10:38AM +0800, YueHaibing wrote:
> >> syzkaller report this:
> >> BUG: memory leak
> >> unreferenced object 0xffffc9000488d000 (size 9195520):
> >>   comm "syz-executor.0", pid 2752, jiffies 4294787496 (age 18.757s)
> >>   hex dump (first 32 bytes):
> >>     ff ff ff ff ff ff ff ff a8 00 00 00 01 00 00 00  ................
> >>     02 00 00 00 00 00 00 00 80 a1 7a c1 ff ff ff ff  ..........z.....
> >>   backtrace:
> >>     [<000000000863775c>] __vmalloc_node mm/vmalloc.c:1795 [inline]
> >>     [<000000000863775c>] __vmalloc_node_flags mm/vmalloc.c:1809 [inline]
> >>     [<000000000863775c>] vmalloc+0x8c/0xb0 mm/vmalloc.c:1831
> >>     [<000000003f668111>] kernel_read_file+0x58f/0x7d0 fs/exec.c:924
> >>     [<000000002385813f>] kernel_read_file_from_fd+0x49/0x80 fs/exec.c:993
> >>     [<0000000011953ff1>] __do_sys_finit_module+0x13b/0x2a0 kernel/module.c:3895
> >>     [<000000006f58491f>] do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
> >>     [<00000000ee78baf4>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
> >>     [<00000000241f889b>] 0xffffffffffffffff
> >>
> >> It should goto 'out_free' lable to free allocated buf while kernel_read
> >> fails.
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> >Applied.
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> >
> >This must be applied to stables as well...
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> > It's already in all relevant stable trees...
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> I only can see in longterm 4.19.
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> What about 4.9 and 4.14?

It was in the queue already for that (you can see it on git.kernel.org),
and they are now part of the -rc releases that are currently out for
review.

thanks,

greg k-h