From 755112b35cdd181dffd704b42ca6a788cc0e3326 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 5 May 2021 22:01:16 +0200 Subject: s390/traps: add struct to access transactional diagnostic block gcc-11 warns: arch/s390/kernel/traps.c: In function __do_pgm_check: arch/s390/kernel/traps.c:319:17: warning: memcpy reading 256 bytes from a region of size 0 [-Wstringop-overread] 319 | memcpy(¤t->thread.trap_tdb, &S390_lowcore.pgm_tdb, 256); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct pgm_tdb to struct lowcore and copy that. Signed-off-by: Sven Schnelle Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/include/asm/lowcore.h | 6 +++++- arch/s390/include/asm/processor.h | 2 +- arch/s390/kernel/ptrace.c | 4 +++- arch/s390/kernel/traps.c | 4 ++-- 4 files changed, 11 insertions(+), 5 deletions(-) diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index d08813c7f462..3c85c60f56ac 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -17,6 +17,10 @@ #define LC_ORDER 1 #define LC_PAGES 2 +struct pgm_tdb { + u64 data[32]; +}; + struct lowcore { __u8 pad_0x0000[0x0014-0x0000]; /* 0x0000 */ __u32 ipl_parmblock_ptr; /* 0x0014 */ @@ -184,7 +188,7 @@ struct lowcore { __u8 pad_0x1400[0x1800-0x1400]; /* 0x1400 */ /* Transaction abort diagnostic block */ - __u8 pgm_tdb[256]; /* 0x1800 */ + struct pgm_tdb pgm_tdb; /* 0x1800 */ __u8 pad_0x1900[0x2000-0x1900]; /* 0x1900 */ } __packed __aligned(8192); diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 023a15dc25a3..6d3055f7329a 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -129,7 +129,7 @@ struct thread_struct { struct runtime_instr_cb *ri_cb; struct gs_cb *gs_cb; /* Current guarded storage cb */ struct gs_cb *gs_bc_cb; /* Broadcast guarded storage cb */ - unsigned char trap_tdb[256]; /* Transaction abort diagnose block */ + struct pgm_tdb trap_tdb; /* Transaction abort diagnose block */ /* * Warning: 'fpu' is dynamically-sized. It *MUST* be at * the end. diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c index 18b3416fd663..0ea3d02b378d 100644 --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -975,10 +975,12 @@ static int s390_tdb_get(struct task_struct *target, struct membuf to) { struct pt_regs *regs = task_pt_regs(target); + size_t size; if (!(regs->int_code & 0x200)) return -ENODATA; - return membuf_write(&to, target->thread.trap_tdb, 256); + size = sizeof(target->thread.trap_tdb.data); + return membuf_write(&to, target->thread.trap_tdb.data, size); } static int s390_tdb_set(struct task_struct *target, diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c index 8dd23c703718..019c5748b607 100644 --- a/arch/s390/kernel/traps.c +++ b/arch/s390/kernel/traps.c @@ -36,7 +36,7 @@ static inline void __user *get_trap_ip(struct pt_regs *regs) unsigned long address; if (regs->int_code & 0x200) - address = *(unsigned long *)(current->thread.trap_tdb + 24); + address = current->thread.trap_tdb.data[3]; else address = regs->psw.addr; return (void __user *) (address - (regs->int_code >> 16)); @@ -318,7 +318,7 @@ void noinstr __do_pgm_check(struct pt_regs *regs) if (S390_lowcore.pgm_code & 0x0200) { /* transaction abort */ - memcpy(¤t->thread.trap_tdb, &S390_lowcore.pgm_tdb, 256); + current->thread.trap_tdb = S390_lowcore.pgm_tdb; } if (S390_lowcore.pgm_code & PGM_INT_CODE_PER) { -- cgit v1.2.3