[linux-block.git] / arch / x86 / kernel / signal_compat.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/compat.h>
#include <linux/uaccess.h>
#include <linux/ptrace.h>

/*
 * The compat_siginfo_t structure and handing code is very easy
 * to break in several ways.  It must always be updated when new
 * updates are made to the main siginfo_t, and
 * copy_siginfo_to_user32() must be updated when the
 * (arch-independent) copy_siginfo_to_user() is updated.
 *
 * It is also easy to put a new member in the compat_siginfo_t
 * which has implicit alignment which can move internal structure
 * alignment around breaking the ABI.  This can happen if you,
 * for instance, put a plain 64-bit value in there.
 */
static inline void signal_compat_build_tests(void)
{
	int _sifields_offset = offsetof(compat_siginfo_t, _sifields);

	/*
	 * If adding a new si_code, there is probably new data in
	 * the siginfo.  Make sure folks bumping the si_code
	 * limits also have to look at this code.  Make sure any
	 * new fields are handled in copy_siginfo_to_user32()!
	 */
	BUILD_BUG_ON(NSIGILL  != 11);
	BUILD_BUG_ON(NSIGFPE  != 15);
	BUILD_BUG_ON(NSIGSEGV != 9);
	BUILD_BUG_ON(NSIGBUS  != 5);
	BUILD_BUG_ON(NSIGTRAP != 6);
	BUILD_BUG_ON(NSIGCHLD != 6);
	BUILD_BUG_ON(NSIGSYS  != 2);

	/* This is part of the ABI and can never change in size: */
	BUILD_BUG_ON(sizeof(siginfo_t) != 128);
	BUILD_BUG_ON(sizeof(compat_siginfo_t) != 128);

	/* This is a part of the ABI and can never change in alignment */
	BUILD_BUG_ON(__alignof__(siginfo_t) != 8);
	BUILD_BUG_ON(__alignof__(compat_siginfo_t) != 4);

	/*
	 * The offsets of all the (unioned) si_fields are fixed
	 * in the ABI, of course.  Make sure none of them ever
	 * move and are always at the beginning:
	 */
	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields) != 3 * sizeof(int));
#define CHECK_CSI_OFFSET(name)	  BUILD_BUG_ON(_sifields_offset != offsetof(compat_siginfo_t, _sifields.name))

	BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0);
	BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4);
	BUILD_BUG_ON(offsetof(siginfo_t, si_code)  != 8);

	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_signo) != 0);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_errno) != 4);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_code)  != 8);
	 /*
	 * Ensure that the size of each si_field never changes.
	 * If it does, it is a sign that the
	 * copy_siginfo_to_user32() code below needs to updated
	 * along with the size in the CHECK_SI_SIZE().
	 *
	 * We repeat this check for both the generic and compat
	 * siginfos.
	 *
	 * Note: it is OK for these to grow as long as the whole
	 * structure stays within the padding size (checked
	 * above).
	 */
#define CHECK_CSI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((compat_siginfo_t *)0)->_sifields.name))
#define CHECK_SI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((siginfo_t *)0)->_sifields.name))

	CHECK_CSI_OFFSET(_kill);
	CHECK_CSI_SIZE  (_kill, 2*sizeof(int));
	CHECK_SI_SIZE   (_kill, 2*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0xC);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);

	CHECK_CSI_OFFSET(_timer);
	CHECK_CSI_SIZE  (_timer, 3*sizeof(int));
	CHECK_SI_SIZE   (_timer, 6*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_tid)     != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x14);
	BUILD_BUG_ON(offsetof(siginfo_t, si_value)   != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_tid)     != 0x0C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_overrun) != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value)   != 0x14);

	CHECK_CSI_OFFSET(_rt);
	CHECK_CSI_SIZE  (_rt, 3*sizeof(int));
	CHECK_SI_SIZE   (_rt, 4*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_pid)   != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_uid)   != 0x14);
	BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid)   != 0x0C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid)   != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14);

	CHECK_CSI_OFFSET(_sigchld);
	CHECK_CSI_SIZE  (_sigchld, 5*sizeof(int));
	CHECK_SI_SIZE   (_sigchld, 8*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_pid)    != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_uid)    != 0x14);
	BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x18);
	BUILD_BUG_ON(offsetof(siginfo_t, si_utime)  != 0x20);
	BUILD_BUG_ON(offsetof(siginfo_t, si_stime)  != 0x28);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid)    != 0x0C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid)    != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_status) != 0x14);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_utime)  != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_stime)  != 0x1C);

#ifdef CONFIG_X86_X32_ABI
	CHECK_CSI_OFFSET(_sigchld_x32);
	CHECK_CSI_SIZE  (_sigchld_x32, 7*sizeof(int));
	/* no _sigchld_x32 in the generic siginfo_t */
	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._utime)  != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._stime)  != 0x20);
#endif

	CHECK_CSI_OFFSET(_sigfault);
	CHECK_CSI_SIZE  (_sigfault, 4*sizeof(int));
	CHECK_SI_SIZE   (_sigfault, 8*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr) != 0x0C);

	BUILD_BUG_ON(offsetof(siginfo_t, si_trapno) != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_trapno) != 0x10);

	BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_lsb) != 0x10);

	BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x20);
	BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x28);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_lower) != 0x14);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_upper) != 0x18);

	BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x20);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pkey) != 0x14);

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x18);
	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x20);
	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_flags) != 0x24);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_data) != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_type) != 0x14);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_flags) != 0x18);

	CHECK_CSI_OFFSET(_sigpoll);
	CHECK_CSI_SIZE  (_sigpoll, 2*sizeof(int));
	CHECK_SI_SIZE   (_sigpoll, 4*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_band)   != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_fd)     != 0x18);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_band) != 0x0C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_fd)   != 0x10);

	CHECK_CSI_OFFSET(_sigsys);
	CHECK_CSI_SIZE  (_sigsys, 3*sizeof(int));
	CHECK_SI_SIZE   (_sigsys, 4*sizeof(int));

	BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x10);
	BUILD_BUG_ON(offsetof(siginfo_t, si_syscall)   != 0x18);
	BUILD_BUG_ON(offsetof(siginfo_t, si_arch)      != 0x1C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_call_addr) != 0x0C);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_syscall)   != 0x10);
	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_arch)      != 0x14);

	/* any new si_fields should be added here */
}

void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact)
{
	signal_compat_build_tests();

	if (!act)
		return;

	if (in_ia32_syscall())
		act->sa.sa_flags |= SA_IA32_ABI;
	if (in_x32_syscall())
		act->sa.sa_flags |= SA_X32_ABI;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
c0bfd26e BG	2	#include <linux/compat.h>
c0bfd26e BG	3	#include <linux/uaccess.h>
68463510	4	#include <linux/ptrace.h>
c0bfd26e	5
02e8fda2 DH	6	/*
	7	* The compat_siginfo_t structure and handing code is very easy
	8	* to break in several ways. It must always be updated when new
	9	* updates are made to the main siginfo_t, and
	10	* copy_siginfo_to_user32() must be updated when the
	11	* (arch-independent) copy_siginfo_to_user() is updated.
	12	*
	13	* It is also easy to put a new member in the compat_siginfo_t
	14	* which has implicit alignment which can move internal structure
	15	* alignment around breaking the ABI. This can happen if you,
	16	* for instance, put a plain 64-bit value in there.
	17	*/
	18	static inline void signal_compat_build_tests(void)
	19	{
	20	int _sifields_offset = offsetof(compat_siginfo_t, _sifields);
	21
	22	/*
	23	* If adding a new si_code, there is probably new data in
	24	* the siginfo. Make sure folks bumping the si_code
	25	* limits also have to look at this code. Make sure any
	26	* new fields are handled in copy_siginfo_to_user32()!
	27	*/
ac54058d	28	BUILD_BUG_ON(NSIGILL != 11);
75abf642	29	BUILD_BUG_ON(NSIGFPE != 15);
74f10824	30	BUILD_BUG_ON(NSIGSEGV != 9);
02e8fda2	31	BUILD_BUG_ON(NSIGBUS != 5);
fb6cc127	32	BUILD_BUG_ON(NSIGTRAP != 6);
02e8fda2	33	BUILD_BUG_ON(NSIGCHLD != 6);
1d7637d8	34	BUILD_BUG_ON(NSIGSYS != 2);
02e8fda2 DH	35
02e8fda2 DH	36	/* This is part of the ABI and can never change in size: */
50ae8130	37	BUILD_BUG_ON(sizeof(siginfo_t) != 128);
02e8fda2	38	BUILD_BUG_ON(sizeof(compat_siginfo_t) != 128);
50ae8130 EB	39
	40	/* This is a part of the ABI and can never change in alignment */
	41	BUILD_BUG_ON(__alignof__(siginfo_t) != 8);
	42	BUILD_BUG_ON(__alignof__(compat_siginfo_t) != 4);
	43
02e8fda2 DH	44	/*
	45	* The offsets of all the (unioned) si_fields are fixed
	46	* in the ABI, of course. Make sure none of them ever
	47	* move and are always at the beginning:
	48	*/
	49	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields) != 3 * sizeof(int));
	50	#define CHECK_CSI_OFFSET(name) BUILD_BUG_ON(_sifields_offset != offsetof(compat_siginfo_t, _sifields.name))
	51
f6a01549 EB	52	BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0);
	53	BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4);
	54	BUILD_BUG_ON(offsetof(siginfo_t, si_code) != 8);
	55
	56	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_signo) != 0);
	57	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_errno) != 4);
	58	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_code) != 8);
02e8fda2 DH	59	/*
	60	* Ensure that the size of each si_field never changes.
	61	* If it does, it is a sign that the
	62	* copy_siginfo_to_user32() code below needs to updated
	63	* along with the size in the CHECK_SI_SIZE().
	64	*
	65	* We repeat this check for both the generic and compat
	66	* siginfos.
	67	*
	68	* Note: it is OK for these to grow as long as the whole
	69	* structure stays within the padding size (checked
	70	* above).
	71	*/
	72	#define CHECK_CSI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((compat_siginfo_t *)0)->_sifields.name))
	73	#define CHECK_SI_SIZE(name, size) BUILD_BUG_ON(size != sizeof(((siginfo_t *)0)->_sifields.name))
	74
	75	CHECK_CSI_OFFSET(_kill);
	76	CHECK_CSI_SIZE (_kill, 2*sizeof(int));
	77	CHECK_SI_SIZE (_kill, 2*sizeof(int));
	78
f6a01549 EB	79	BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
	80	BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
	81	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0xC);
	82	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
	83
02e8fda2	84	CHECK_CSI_OFFSET(_timer);
2f82a46f	85	CHECK_CSI_SIZE (_timer, 3*sizeof(int));
02e8fda2 DH	86	CHECK_SI_SIZE (_timer, 6*sizeof(int));
02e8fda2 DH	87
f6a01549 EB	88	BUILD_BUG_ON(offsetof(siginfo_t, si_tid) != 0x10);
	89	BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x14);
	90	BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18);
	91	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_tid) != 0x0C);
	92	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_overrun) != 0x10);
	93	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14);
	94
02e8fda2 DH	95	CHECK_CSI_OFFSET(_rt);
	96	CHECK_CSI_SIZE (_rt, 3*sizeof(int));
	97	CHECK_SI_SIZE (_rt, 4*sizeof(int));
	98
f6a01549 EB	99	BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
	100	BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
	101	BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18);
	102	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C);
	103	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
	104	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14);
	105
02e8fda2 DH	106	CHECK_CSI_OFFSET(_sigchld);
	107	CHECK_CSI_SIZE (_sigchld, 5*sizeof(int));
	108	CHECK_SI_SIZE (_sigchld, 8*sizeof(int));
	109
f6a01549 EB	110	BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10);
	111	BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14);
	112	BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x18);
	113	BUILD_BUG_ON(offsetof(siginfo_t, si_utime) != 0x20);
	114	BUILD_BUG_ON(offsetof(siginfo_t, si_stime) != 0x28);
	115	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C);
	116	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10);
	117	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_status) != 0x14);
	118	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_utime) != 0x18);
	119	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_stime) != 0x1C);
	120
b713da69	121	#ifdef CONFIG_X86_X32_ABI
02e8fda2 DH	122	CHECK_CSI_OFFSET(_sigchld_x32);
	123	CHECK_CSI_SIZE (_sigchld_x32, 7*sizeof(int));
	124	/* no _sigchld_x32 in the generic siginfo_t */
f6a01549 EB	125	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._utime) != 0x18);
f6a01549 EB	126	BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._stime) != 0x20);
b713da69	127	#endif
02e8fda2 DH	128
	129	CHECK_CSI_OFFSET(_sigfault);
	130	CHECK_CSI_SIZE (_sigfault, 4*sizeof(int));
	131	CHECK_SI_SIZE (_sigfault, 8*sizeof(int));
	132
f6a01549 EB	133	BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x10);
	134	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr) != 0x0C);
	135
add0b32e EB	136	BUILD_BUG_ON(offsetof(siginfo_t, si_trapno) != 0x18);
	137	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_trapno) != 0x10);
	138
f6a01549 EB	139	BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x18);
	140	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_lsb) != 0x10);
	141
	142	BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x20);
	143	BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x28);
	144	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_lower) != 0x14);
	145	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_upper) != 0x18);
	146
	147	BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x20);
	148	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pkey) != 0x14);
	149
0683b531 EB	150	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x18);
0683b531 EB	151	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x20);
78ed93d7	152	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_flags) != 0x24);
0683b531 EB	153	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_data) != 0x10);
0683b531 EB	154	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_type) != 0x14);
78ed93d7	155	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_flags) != 0x18);
fb6cc127	156
02e8fda2 DH	157	CHECK_CSI_OFFSET(_sigpoll);
	158	CHECK_CSI_SIZE (_sigpoll, 2*sizeof(int));
	159	CHECK_SI_SIZE (_sigpoll, 4*sizeof(int));
	160
f6a01549 EB	161	BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x10);
	162	BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x18);
	163	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_band) != 0x0C);
	164	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_fd) != 0x10);
	165
02e8fda2 DH	166	CHECK_CSI_OFFSET(_sigsys);
	167	CHECK_CSI_SIZE (_sigsys, 3*sizeof(int));
	168	CHECK_SI_SIZE (_sigsys, 4*sizeof(int));
	169
f6a01549 EB	170	BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x10);
	171	BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x18);
	172	BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x1C);
	173	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_call_addr) != 0x0C);
	174	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_syscall) != 0x10);
	175	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_arch) != 0x14);
	176
02e8fda2 DH	177	/* any new si_fields should be added here */
	178	}
	179
68463510 DS	180	void sigaction_compat_abi(struct k_sigaction act, struct k_sigaction oact)
68463510 DS	181	{
ea64d5ac EB	182	signal_compat_build_tests();
ea64d5ac EB	183
68463510 DS	184	if (!act)
	185	return;
	186
68463510 DS	187	if (in_ia32_syscall())
	188	act->sa.sa_flags \|= SA_IA32_ABI;
	189	if (in_x32_syscall())
	190	act->sa.sa_flags \|= SA_X32_ABI;
	191	}