diff options
| author | Alistair Strachan <astrachan@google.com> | 2018-12-14 23:36:37 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2018-12-15 11:37:51 +0100 |
| commit | cd01544a268ad8ee5b1dfe42c4393f1095f86879 (patch) | |
| tree | a5b68cc57c52ea8f8e353e91375d56c35c470804 | |
| parent | x86/mm: Fix decoy address handling vs 32-bit builds (diff) | |
| download | linux-cd01544a268ad8ee5b1dfe42c4393f1095f86879.tar.xz linux-cd01544a268ad8ee5b1dfe42c4393f1095f86879.zip | |
x86/vdso: Pass --eh-frame-hdr to the linker
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
| -rw-r--r-- | arch/x86/entry/vdso/Makefile | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 0624bf2266fd..5bfe2243a08f 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -171,7 +171,8 @@ 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 # |