Commit a0e31f3a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-v5.13-rc3' of... 

Merge branch 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull siginfo fix from Eric Biederman:
 "During the merge window an issue with si_perf and the siginfo ABI came
  up. The alpha and sparc siginfo structure layout had changed with the
  addition of SIGTRAP TRAP_PERF and the new field si_perf.

  The reason only alpha and sparc were affected is that they are the
  only architectures that use si_trapno.

  Looking deeper it was discovered that si_trapno is used for only a few
  select signals on alpha and sparc, and that none of the other
  _sigfault fields past si_addr are used at all. Which means technically
  no regression on alpha and sparc.

  While the alignment concerns might be dismissed the abuse of si_errno
  by SIGTRAP TRAP_PERF does have the potential to cause regressions in
  existing userspace.

  While we still have time before userspace starts using and depending
  on the new definition siginfo for SIGTRAP TRAP_PERF this set of
  changes cleans up siginfo_t.

   - The si_trapno field is demoted from magic alpha and sparc status
     and made an ordinary union member of the _sigfault member of
     siginfo_t. Without moving it of course.

   - si_perf is replaced with si_perf_data and si_perf_type ending the
     abuse of si_errno.

   - Unnecessary additions to signalfd_siginfo are removed"

* 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo
  signal: Deliver all of the siginfo perf data in _perf
  signal: Factor force_sig_perf out of perf_sigtrap
  signal: Implement SIL_FAULT_TRAPNO
  siginfo: Move si_trapno inside the union inside _si_fault
parents c1f47ebc 922e3013

arch/m68k/kernel/signal.c

+2 −1
Original line number Diff line number Diff line
@@ -623,7 +623,8 @@ static inline void siginfo_build_tests(void) 
	BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x12);



	/* _sigfault._perf */

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf) != 0x10);

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x10);

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x14);



	/* _sigpoll */

	BUILD_BUG_ON(offsetof(siginfo_t, si_band)   != 0x0c);

arch/x86/kernel/signal_compat.c

+7 −2
Original line number Diff line number Diff line
@@ -127,6 +127,9 @@ static inline void signal_compat_build_tests(void) 
	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);
@@ -138,8 +141,10 @@ static inline void signal_compat_build_tests(void) 
	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) != 0x18);

	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf) != 0x10);

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x18);

	BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x20);

	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_data) != 0x10);

	BUILD_BUG_ON(offsetof(compat_siginfo_t, si_perf_type) != 0x14);



	CHECK_CSI_OFFSET(_sigpoll);

	CHECK_CSI_SIZE  (_sigpoll, 2*sizeof(int));

fs/signalfd.c

+9 −14
Original line number Diff line number Diff line
@@ -114,29 +114,24 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, 
		break;

	case SIL_FAULT_BNDERR:

	case SIL_FAULT_PKUERR:

	case SIL_PERF_EVENT:

		/*

		 * Fall through to the SIL_FAULT case.  Both SIL_FAULT_BNDERR

		 * and SIL_FAULT_PKUERR are only generated by faults that

		 * deliver them synchronously to userspace.  In case someone

		 * injects one of these signals and signalfd catches it treat

		 * it as SIL_FAULT.

		 * Fall through to the SIL_FAULT case.  SIL_FAULT_BNDERR,

		 * SIL_FAULT_PKUERR, and SIL_PERF_EVENT are only

		 * generated by faults that deliver them synchronously to

		 * userspace.  In case someone injects one of these signals

		 * and signalfd catches it treat it as SIL_FAULT.

		 */

	case SIL_FAULT:

		new.ssi_addr = (long) kinfo->si_addr;

#ifdef __ARCH_SI_TRAPNO

		new.ssi_trapno = kinfo->si_trapno;

#endif

		break;

	case SIL_FAULT_MCEERR:

	case SIL_FAULT_TRAPNO:

		new.ssi_addr = (long) kinfo->si_addr;

#ifdef __ARCH_SI_TRAPNO

		new.ssi_trapno = kinfo->si_trapno;

#endif

		new.ssi_addr_lsb = (short) kinfo->si_addr_lsb;

		break;

	case SIL_PERF_EVENT:

	case SIL_FAULT_MCEERR:

		new.ssi_addr = (long) kinfo->si_addr;

		new.ssi_perf = kinfo->si_perf;

		new.ssi_addr_lsb = (short) kinfo->si_addr_lsb;

		break;

	case SIL_CHLD:

		new.ssi_pid    = kinfo->si_pid;

include/linux/compat.h

+6 −4
Original line number Diff line number Diff line
@@ -213,12 +213,11 @@ typedef struct compat_siginfo { 
		/* SIGILL, SIGFPE, SIGSEGV, SIGBUS, SIGTRAP, SIGEMT */

		struct {

			compat_uptr_t _addr;	/* faulting insn/memory ref. */

#ifdef __ARCH_SI_TRAPNO

			int _trapno;	/* TRAP # which caused the signal */

#endif

#define __COMPAT_ADDR_BND_PKEY_PAD  (__alignof__(compat_uptr_t) < sizeof(short) ? \

				     sizeof(short) : __alignof__(compat_uptr_t))

			union {

				/* used on alpha and sparc */

				int _trapno;	/* TRAP # which caused the signal */

				/*

				 * used when si_code=BUS_MCEERR_AR or

				 * used when si_code=BUS_MCEERR_AO
@@ -236,7 +235,10 @@ typedef struct compat_siginfo { 
					u32 _pkey;

				} _addr_pkey;

				/* used when si_code=TRAP_PERF */

				compat_ulong_t _perf;

				struct {

					compat_ulong_t _data;

					u32 _type;

				} _perf;

			};

		} _sigfault;

include/linux/sched/signal.h

+1 −0
Original line number Diff line number Diff line
@@ -326,6 +326,7 @@ int send_sig_mceerr(int code, void __user *, short, struct task_struct *); 


int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper);

int force_sig_pkuerr(void __user *addr, u32 pkey);

int force_sig_perf(void __user *addr, u32 type, u64 sig_data);



int force_sig_ptrace_errno_trap(int errno, void __user *addr);