From: Josh Poimboeuf Date: Fri, 6 Mar 2026 18:28:14 +0000 (-0800) Subject: objtool: Fix another stack overflow in validate_branch() X-Git-Tag: v7.0-rc4~9^2 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9a73f085dc91980ab7fcc5e9716f4449424b3b59;p=thirdparty%2Fkernel%2Flinux.git objtool: Fix another stack overflow in validate_branch() The insn state is getting saved on the stack twice for each recursive iteration. No need for that, once is enough. Fixes the following reported stack overflow: drivers/scsi/qla2xxx/qla_dbg.o: error: SIGSEGV: objtool stack overflow! Segmentation fault Fixes: 70589843b36f ("objtool: Add option to trace function validation") Reported-by: Arnd Bergmann Closes: https://lore.kernel.org/90956545-2066-46e3-b547-10c884582eb0@app.fastmail.com Link: https://patch.msgid.link/8b97f62d083457f3b0a29a424275f7957dd3372f.1772821683.git.jpoimboe@kernel.org Signed-off-by: Josh Poimboeuf --- diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 786b2f2adbab..91b3ff4803cf 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -3748,7 +3748,7 @@ static void checksum_update_insn(struct objtool_file *file, struct symbol *func, static int validate_branch(struct objtool_file *file, struct symbol *func, struct instruction *insn, struct insn_state state); static int do_validate_branch(struct objtool_file *file, struct symbol *func, - struct instruction *insn, struct insn_state state); + struct instruction *insn, struct insn_state *state); static int validate_insn(struct objtool_file *file, struct symbol *func, struct instruction *insn, struct insn_state *statep, @@ -4013,7 +4013,7 @@ static int validate_insn(struct objtool_file *file, struct symbol *func, * tools/objtool/Documentation/objtool.txt. */ static int do_validate_branch(struct objtool_file *file, struct symbol *func, - struct instruction *insn, struct insn_state state) + struct instruction *insn, struct insn_state *state) { struct instruction *next_insn, *prev_insn = NULL; bool dead_end; @@ -4044,7 +4044,7 @@ static int do_validate_branch(struct objtool_file *file, struct symbol *func, return 1; } - ret = validate_insn(file, func, insn, &state, prev_insn, next_insn, + ret = validate_insn(file, func, insn, state, prev_insn, next_insn, &dead_end); if (!insn->trace) { @@ -4055,7 +4055,7 @@ static int do_validate_branch(struct objtool_file *file, struct symbol *func, } if (!dead_end && !next_insn) { - if (state.cfi.cfa.base == CFI_UNDEFINED) + if (state->cfi.cfa.base == CFI_UNDEFINED) return 0; if (file->ignore_unreachables) return 0; @@ -4080,7 +4080,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, int ret; trace_depth_inc(); - ret = do_validate_branch(file, func, insn, state); + ret = do_validate_branch(file, func, insn, &state); trace_depth_dec(); return ret;