MFC 313407,313449: Copy ELF machine/flags from binaries to core dumps.

313407:
Copy the e_machine and e_flags fields from the binary into an ELF core dump.

In the kernel, cache the machine and flags fields from ELF header to use in
the ELF header of a core dump. For gcore, the copy these fields over from
the ELF header in the binary.

This matters for platforms which encode ABI information in the flags field
(such as o32 vs n32 on MIPS).

313449:
Trim trailing whitespace (mostly introduced in r313407).

Sponsored by:	DARPA / AFRL

3 files changed, 12 insertions, 8 deletions

diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 491b9dd..6ae6d67 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -1079,6 +1079,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 	imgp->interpreted = 0;
 	imgp->reloc_base = addr;
 	imgp->proc->p_osrel = osrel;
+	imgp->proc->p_elf_machine = hdr->e_machine;
+	imgp->proc->p_elf_flags = hdr->e_flags;
 
  ret:
 	free(interp_buf, M_TEMP);
@@ -1682,15 +1684,11 @@ __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs,
 	ehdr->e_ident[EI_ABIVERSION] = 0;
 	ehdr->e_ident[EI_PAD] = 0;
 	ehdr->e_type = ET_CORE;
-#if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32
-	ehdr->e_machine = ELF_ARCH32;
-#else
-	ehdr->e_machine = ELF_ARCH;
-#endif
+	ehdr->e_machine = td->td_proc->p_elf_machine;
 	ehdr->e_version = EV_CURRENT;
 	ehdr->e_entry = 0;
 	ehdr->e_phoff = sizeof(Elf_Ehdr);
-	ehdr->e_flags = 0;
+	ehdr->e_flags = td->td_proc->p_elf_flags;
 	ehdr->e_ehsize = sizeof(Elf_Ehdr);
 	ehdr->e_phentsize = sizeof(Elf_Phdr);
 	ehdr->e_phnum = numsegs + 1;
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index bb92861..c7680aa 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -408,6 +408,8 @@ do_fork(struct thread *td, struct fork_req *fr, struct proc *p2, struct thread *
 
 	bcopy(&p1->p_startcopy, &p2->p_startcopy,
 	    __rangeof(struct proc, p_startcopy, p_endcopy));
+	p2->p_elf_machine = p1->p_elf_machine;
+	p2->p_elf_flags = p1->p_elf_flags;
 	pargs_hold(p2->p_args);
 
 	PROC_UNLOCK(p1);
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 2439e11..5946298 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -316,7 +316,7 @@ struct thread {
 	} td_state;			/* (t) thread state */
 	union {
 		register_t	tdu_retval[2];
-		off_t		tdu_off;	
+		off_t		tdu_off;
 	} td_uretoff;			/* (k) Syscall aux returns. */
 #define td_retval	td_uretoff.tdu_retval
 	u_int		td_cowgen;	/* (k) Generation of COW pointers. */
@@ -626,8 +626,10 @@ struct proc {
 					       our subtree. */
 	u_int		p_xexit;	/* (c) Exit code. */
 	u_int		p_xsig;		/* (c) Stop/kill sig. */
+
 /* End area that is copied on creation. */
-#define	p_endcopy	p_xsig
+#define	p_endcopy	p_pgrp
+
 	struct pgrp	*p_pgrp;	/* (c + e) Pointer to process group. */
 	struct knlist	*p_klist;	/* (c) Knotes attached to this proc. */
 	int		p_numthreads;	/* (c) Number of threads. */
@@ -657,6 +659,8 @@ struct proc {
 	LIST_ENTRY(proc) p_orphan;	/* (e) List of orphan processes. */
 	LIST_HEAD(, proc) p_orphans;	/* (e) Pointer to list of orphans. */
 	u_int		p_ptevents;	/* (c) ptrace() event mask. */
+	uint16_t	p_elf_machine;	/* (x) ELF machine type */
+	uint64_t	p_elf_flags;	/* (x) ELF flags */
 };
 
 #define	p_session	p_pgrp->pg_session