Commit 755112b3 authored by Sven Schnelle's avatar Sven Schnelle Committed by Vasily Gorbik
Browse files

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(&current->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: default avatarSven Schnelle <svens@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 6c6a07fc

arch/s390/include/asm/lowcore.h

+5 −1
Original line number Diff line number Diff line
@@ -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);

arch/s390/include/asm/processor.h

+1 −1
Original line number Diff line number Diff line
@@ -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.

arch/s390/kernel/ptrace.c

+3 −1
Original line number Diff line number Diff line
@@ -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,

arch/s390/kernel/traps.c

+2 −2
Original line number Diff line number Diff line
@@ -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(&current->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) {