lkml.org 
[lkml]   [2023]   [Feb]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip: objtool/core] objtool: Fix ORC 'signal' propagation
The following commit has been merged into the objtool/core branch of tip:

Commit-ID: 801d48faf6bbf985d14aa1027889f3a3fe4206f1
Gitweb: https://git.kernel.org/tip/801d48faf6bbf985d14aa1027889f3a3fe4206f1
Author: Josh Poimboeuf <jpoimboe@kernel.org>
AuthorDate: Thu, 16 Feb 2023 12:34:41 -08:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Tue, 21 Feb 2023 16:40:14 +01:00

objtool: Fix ORC 'signal' propagation

There have been some recently reported ORC unwinder warnings like:

WARNING: can't access registers at entry_SYSCALL_64_after_hwframe+0x63/0xcd
WARNING: stack going in the wrong direction? at __sys_setsockopt+0x2c6/0x5b0 net/socket.c:2271

And a KASAN warning:

BUG: KASAN: stack-out-of-bounds in unwind_next_frame (arch/x86/include/asm/ptrace.h:136 arch/x86/kernel/unwind_orc.c:455)

It turns out the 'signal' bit isn't getting propagated from the unwind
hints to the ORC entries, making the unwinder confused at times.

Fixes: ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/97eef9db60cd86d376a9a40d49d77bb67a8f6526.1676579666.git.jpoimboe@kernel.org
---
tools/objtool/check.c | 1 +
tools/objtool/include/objtool/cfi.h | 1 +
tools/objtool/orc_gen.c | 1 +
3 files changed, 3 insertions(+)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index b0b467d..5822de3 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2330,6 +2330,7 @@ static int read_unwind_hints(struct objtool_file *file)

cfi.cfa.offset = bswap_if_needed(file->elf, hint->sp_offset);
cfi.type = hint->type;
+ cfi.signal = hint->signal;
cfi.end = hint->end;

insn->cfi = cfi_hash_find_or_add(&cfi);
diff --git a/tools/objtool/include/objtool/cfi.h b/tools/objtool/include/objtool/cfi.h
index f11d1ac..b1258e7 100644
--- a/tools/objtool/include/objtool/cfi.h
+++ b/tools/objtool/include/objtool/cfi.h
@@ -34,6 +34,7 @@ struct cfi_state {
unsigned char type;
bool bp_scratch;
bool drap;
+ bool signal;
bool end;
};

diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c
index 1f22b7e..57a4527 100644
--- a/tools/objtool/orc_gen.c
+++ b/tools/objtool/orc_gen.c
@@ -27,6 +27,7 @@ static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi,
}

orc->end = cfi->end;
+ orc->signal = cfi->signal;

if (cfi->cfa.base == CFI_UNDEFINED) {
orc->sp_reg = ORC_REG_UNDEFINED;
\
 
 \ /
  Last update: 2023-03-27 00:30    [W:0.078 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site