6.6-stable review patch. If anyone has any objections, please let me know.
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From: Josh Poimboeuf jpoimboe@kernel.org
[ Upstream commit 69d41d6dafff0967565b971d950bd10443e4076c ]
Check 'prev_insn' before dereferencing it.
Fixes: bd841d6154f5 ("objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings") Reported-by: Arnd Bergmann arnd@arndb.de Reported-by: Ingo Molnar mingo@kernel.org Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org Link: https://lore.kernel.org/r/5df4ff89c9e4b9e788b77b0531234ffa7ba03e9e.174313620...
Closes: https://lore.kernel.org/d86b4cc6-0b97-4095-8793-a7384410b8ab@app.fastmail.co... Closes: https://lore.kernel.org/Z-V_rruKY0-36pqA@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/objtool/check.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5824aa68ff961..36412f1881e61 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -4089,7 +4089,7 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio * It may also insert a UD2 after calling a __noreturn function. */ prev_insn = prev_insn_same_sec(file, insn); - if (prev_insn->dead_end && + if (prev_insn && prev_insn->dead_end && (insn->type == INSN_BUG || (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest && insn->jump_dest->type == INSN_BUG)))