On Tue, May 14, 2019 at 08:32:49AM -0400, Sasha Levin wrote:
> On Tue, May 14, 2019 at 09:50:04AM +0200, Greg Kroah-Hartman wrote:
> > On Tue, May 14, 2019 at 04:34:29PM +0900, Nobuhiro Iwamatsu wrote:
> > > From: Alistair Strachan <astrachan@xxxxxxxxxx>
> > >
> > > commit cd01544a268ad8ee5b1dfe42c4393f1095f86879 upstream.
> > >
> > > Commit
> > >
> > > 379d98ddf413 ("x86: vdso: Use $LD instead of $CC to link")
> > >
> > > accidentally broke unwinding from userspace, because ld would strip the
> > > .eh_frame sections when linking.
> > >
> > > Originally, the compiler would implicitly add --eh-frame-hdr when
> > > invoking the linker, but when this Makefile was converted from invoking
> > > ld via the compiler, to invoking it directly (like vmlinux does),
> > > the flag was missed. (The EH_FRAME section is important for the VDSO
> > > shared libraries, but not for vmlinux.)
> > >
> > > Fix the problem by explicitly specifying --eh-frame-hdr, which restores
> > > parity with the old method.
> > >
> > > See relevant bug reports for additional info:
> > >
> > > https://bugzilla.kernel.org/show_bug.cgi?id=201741
> > > https://bugzilla.redhat.com/show_bug.cgi?id=1659295
> > >
> > > Fixes: 379d98ddf413 ("x86: vdso: Use $LD instead of $CC to link")
> > > Reported-by: Florian Weimer <fweimer@xxxxxxxxxx>
> > > Reported-by: Carlos O'Donell <carlos@xxxxxxxxxx>
> > > Reported-by: "H. J. Lu" <hjl.tools@xxxxxxxxx>
> > > Signed-off-by: Alistair Strachan <astrachan@xxxxxxxxxx>
> > > Signed-off-by: Borislav Petkov <bp@xxxxxxx>
> > > Tested-by: Laura Abbott <labbott@xxxxxxxxxx>
> > > Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> > > Cc: Carlos O'Donell <carlos@xxxxxxxxxx>
> > > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > > Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
> > > Cc: kernel-team@xxxxxxxxxxx
> > > Cc: Laura Abbott <labbott@xxxxxxxxxx>
> > > Cc: stable <stable@xxxxxxxxxxxxxxx>
> > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > > Cc: X86 ML <x86@xxxxxxxxxx>
> > > Link: https://lkml.kernel.org/r/20181214223637.35954-1-astrachan@xxxxxxxxxx
> > > Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@xxxxxxxxxxxxx>
> > > ---
> > > arch/x86/entry/vdso/Makefile | 3 ++-
> > > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > This is already in the 4.14 stable queue.
> >
> > Sasha, how did you tools miss it for 4.4 and 4.9?
>
> This commit claims it fixes 379d98ddf413 ("x86: vdso: Use $LD instead of
> $CC to link"), which is not in 4.9 nor 4.4
It's already in 4.4.179 :(
I think you need to adjust your scripts, you signed off on the backport :)
I guess we need to also add it to 4.9.y?
greg k-h
