| Message ID | 20190529165944.17004-2-kleber.souza@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix for glibc vdso regression (LP: #1830890) | expand |
On 29.05.19 18:59, Kleber Sacilotto de Souza wrote: > From: Alistair Strachan <astrachan@google.com> > > BugLink: https://bugs.launchpad.net/bugs/1830890 > > 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@redhat.com> > Reported-by: Carlos O'Donell <carlos@redhat.com> > Reported-by: "H. J. Lu" <hjl.tools@gmail.com> > Signed-off-by: Alistair Strachan <astrachan@google.com> > Signed-off-by: Borislav Petkov <bp@suse.de> > Tested-by: Laura Abbott <labbott@redhat.com> > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Carlos O'Donell <carlos@redhat.com> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Joel Fernandes <joel@joelfernandes.org> > Cc: kernel-team@android.com > Cc: Laura Abbott <labbott@redhat.com> > Cc: stable <stable@vger.kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: X86 ML <x86@kernel.org> > Link: https://lkml.kernel.org/r/20181214223637.35954-1-astrachan@google.com > (cherry picked from commit cd01544a268ad8ee5b1dfe42c4393f1095f86879) > Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> > --- > arch/x86/entry/vdso/Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile > index 297dda4d5947..15ed35f5097d 100644 > --- a/arch/x86/entry/vdso/Makefile > +++ b/arch/x86/entry/vdso/Makefile > @@ -159,7 +159,8 @@ quiet_cmd_vdso = VDSO $@ > sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' > > VDSO_LDFLAGS = -shared $(call ld-option, --hash-style=both) \ > - $(call ld-option, --build-id) -Bsymbolic > + $(call ld-option, --build-id) $(call ld-option, --eh-frame-hdr) \ > + -Bsymbolic > GCOV_PROFILE := n > > # >
On 5/29/19 9:59 AM, Kleber Sacilotto de Souza wrote: > From: Alistair Strachan <astrachan@google.com> > > BugLink: https://bugs.launchpad.net/bugs/1830890 > > 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@redhat.com> > Reported-by: Carlos O'Donell <carlos@redhat.com> > Reported-by: "H. J. Lu" <hjl.tools@gmail.com> > Signed-off-by: Alistair Strachan <astrachan@google.com> > Signed-off-by: Borislav Petkov <bp@suse.de> > Tested-by: Laura Abbott <labbott@redhat.com> > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Carlos O'Donell <carlos@redhat.com> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Joel Fernandes <joel@joelfernandes.org> > Cc: kernel-team@android.com > Cc: Laura Abbott <labbott@redhat.com> > Cc: stable <stable@vger.kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: X86 ML <x86@kernel.org> > Link: https://lkml.kernel.org/r/20181214223637.35954-1-astrachan@google.com > (cherry picked from commit cd01544a268ad8ee5b1dfe42c4393f1095f86879) > Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> > --- Acked-by: Connor Kuehl <connor.kuehl@canonical.com> > arch/x86/entry/vdso/Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile > index 297dda4d5947..15ed35f5097d 100644 > --- a/arch/x86/entry/vdso/Makefile > +++ b/arch/x86/entry/vdso/Makefile > @@ -159,7 +159,8 @@ quiet_cmd_vdso = VDSO $@ > sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' > > VDSO_LDFLAGS = -shared $(call ld-option, --hash-style=both) \ > - $(call ld-option, --build-id) -Bsymbolic > + $(call ld-option, --build-id) $(call ld-option, --eh-frame-hdr) \ > + -Bsymbolic > GCOV_PROFILE := n > > # >
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 297dda4d5947..15ed35f5097d 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -159,7 +159,8 @@ quiet_cmd_vdso = VDSO $@ sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' VDSO_LDFLAGS = -shared $(call ld-option, --hash-style=both) \ - $(call ld-option, --build-id) -Bsymbolic + $(call ld-option, --build-id) $(call ld-option, --eh-frame-hdr) \ + -Bsymbolic GCOV_PROFILE := n #