diff options
author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2019-01-18 11:58:06 +0100 |
---|---|---|
committer | Kees Cook <keescook@chromium.org> | 2019-01-20 14:06:40 -0800 |
commit | 560706d5d2589ef510f5436d69ab510a351b8cf7 (patch) | |
tree | aaf4685dbe212ad2e0b996308905a1cd16ffdf29 /scripts | |
parent | 1c7fc5cbc33980acd13d668f1c8f0313d6ae9fd8 (diff) | |
download | lwn-560706d5d2589ef510f5436d69ab510a351b8cf7.tar.gz lwn-560706d5d2589ef510f5436d69ab510a351b8cf7.zip |
gcc-plugins: arm_ssp_per_task_plugin: sign extend the SP mask
The ARM per-task stack protector GCC plugin hits an assert in
the compiler in some case, due to the fact the the SP mask
expression is not sign-extended as it should be. So fix that.
Suggested-by: Kugan Vivekanandarajah <kugan.vivekanandarajah@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'scripts')
-rw-r--r-- | scripts/gcc-plugins/arm_ssp_per_task_plugin.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/scripts/gcc-plugins/arm_ssp_per_task_plugin.c b/scripts/gcc-plugins/arm_ssp_per_task_plugin.c index de70b8470971..a65fbefb8501 100644 --- a/scripts/gcc-plugins/arm_ssp_per_task_plugin.c +++ b/scripts/gcc-plugins/arm_ssp_per_task_plugin.c @@ -13,7 +13,7 @@ static unsigned int arm_pertask_ssp_rtl_execute(void) for (insn = get_insns(); insn; insn = NEXT_INSN(insn)) { const char *sym; rtx body; - rtx masked_sp; + rtx mask, masked_sp; /* * Find a SET insn involving a SYMBOL_REF to __stack_chk_guard @@ -33,12 +33,13 @@ static unsigned int arm_pertask_ssp_rtl_execute(void) * produces the address of the copy of the stack canary value * stored in struct thread_info */ + mask = GEN_INT(sext_hwi(sp_mask, GET_MODE_PRECISION(Pmode))); masked_sp = gen_reg_rtx(Pmode); emit_insn_before(gen_rtx_SET(masked_sp, gen_rtx_AND(Pmode, stack_pointer_rtx, - GEN_INT(sp_mask))), + mask)), insn); SET_SRC(body) = gen_rtx_PLUS(Pmode, masked_sp, |