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| author | Alexander Gordeev <agordeev@linux.ibm.com> | 2021-03-29 18:35:07 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-14 08:22:35 +0200 |
| commit | e0b19c2e3b4f722fa54414e7477aba8e7c50448f (patch) | |
| tree | 8f31c0f9556261ed1a10da6d1306c8d113fc6605 /arch | |
| parent | 4d79ff4485792a13047a611606cea7d64a0bb7db (diff) | |
| download | linux-e0b19c2e3b4f722fa54414e7477aba8e7c50448f.tar.gz linux-e0b19c2e3b4f722fa54414e7477aba8e7c50448f.tar.bz2 linux-e0b19c2e3b4f722fa54414e7477aba8e7c50448f.zip | |
s390/cpcmd: fix inline assembly register clobbering
[ Upstream commit 7a2f91441b2c1d81b77c1cd816a4659f4abc9cbe ]
Register variables initialized using arithmetic. That leads to
kasan instrumentaton code corrupting the registers contents.
Follow GCC guidlines and use temporary variables for assigning
init values to register variables.
Fixes: 94c12cc7d196 ("[S390] Inline assembly cleanup.")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://gcc.gnu.org/onlinedocs/gcc-10.2.0/gcc/Local-Register-Variables.html
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/kernel/cpcmd.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/s390/kernel/cpcmd.c b/arch/s390/kernel/cpcmd.c index af013b4244d3..2da027359798 100644 --- a/arch/s390/kernel/cpcmd.c +++ b/arch/s390/kernel/cpcmd.c @@ -37,10 +37,12 @@ static int diag8_noresponse(int cmdlen) static int diag8_response(int cmdlen, char *response, int *rlen) { + unsigned long _cmdlen = cmdlen | 0x40000000L; + unsigned long _rlen = *rlen; register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf; register unsigned long reg3 asm ("3") = (addr_t) response; - register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L; - register unsigned long reg5 asm ("5") = *rlen; + register unsigned long reg4 asm ("4") = _cmdlen; + register unsigned long reg5 asm ("5") = _rlen; asm volatile( " diag %2,%0,0x8\n" |