From bf166f0b5e0f2e95dfe7a2aa068a52448b72a087 Mon Sep 17 00:00:00 2001 From: jhb Date: Thu, 11 May 2017 17:26:34 +0000 Subject: [PATCH] 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 git-svn-id: svn://svn.freebsd.org/base/stable/10@318192 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- sys/kern/imgact_elf.c | 10 ++++------ sys/kern/kern_fork.c | 2 ++ sys/sys/proc.h | 3 +++ usr.bin/gcore/elfcore.c | 23 +++++++++++++++-------- 4 files changed, 24 insertions(+), 14 deletions(-) diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c index 7f9852260..f4da48a5d 100644 --- a/sys/kern/imgact_elf.c +++ b/sys/kern/imgact_elf.c @@ -1041,6 +1041,8 @@ __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); @@ -1616,15 +1618,11 @@ __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 2b80f9921..cefb539cc 100644 --- a/sys/kern/kern_fork.c +++ b/sys/kern/kern_fork.c @@ -404,6 +404,8 @@ do_fork(struct thread *td, int flags, struct proc *p2, struct thread *td2, 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 9a62aec78..ffc04835c 100644 --- a/sys/sys/proc.h +++ b/sys/sys/proc.h @@ -580,6 +580,7 @@ struct proc { rlim_t p_cpulimit; /* (c) Current CPU limit in seconds. */ signed char p_nice; /* (c) Process "nice" value. */ int p_fibnum; /* in this routing domain XXX MRT */ + /* End area that is copied on creation. */ #define p_endcopy p_xstat @@ -623,6 +624,8 @@ struct proc { struct pgrp *p_pgrp; /* (c + e) Pointer to process group. */ struct filemon *p_filemon; /* (c) filemon-specific data. */ 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 diff --git a/usr.bin/gcore/elfcore.c b/usr.bin/gcore/elfcore.c index 7dcf6a179..be8258f1b 100644 --- a/usr.bin/gcore/elfcore.c +++ b/usr.bin/gcore/elfcore.c @@ -114,8 +114,8 @@ static void *elf_note_procstat_psstrings(void *, size_t *); static void *elf_note_procstat_rlimit(void *, size_t *); static void *elf_note_procstat_umask(void *, size_t *); static void *elf_note_procstat_vmmap(void *, size_t *); -static void elf_puthdr(pid_t, vm_map_entry_t, void *, size_t, size_t, size_t, - int); +static void elf_puthdr(int, pid_t, vm_map_entry_t, void *, size_t, size_t, + size_t, int); static void elf_putnote(int, notefunc_t, void *, struct sbuf *); static void elf_putnotes(pid_t, struct sbuf *, size_t *); static void freemap(vm_map_entry_t); @@ -175,7 +175,7 @@ elf_detach(void) * Write an ELF coredump for the given pid to the given fd. */ static void -elf_coredump(int efd __unused, int fd, pid_t pid) +elf_coredump(int efd, int fd, pid_t pid) { vm_map_entry_t map; struct sseg_closure seginfo; @@ -225,7 +225,7 @@ elf_coredump(int efd __unused, int fd, pid_t pid) hdr = sbuf_data(sb); segoff = sbuf_len(sb); /* Fill in the header. */ - elf_puthdr(pid, map, hdr, hdrsize, notesz, segoff, seginfo.count); + elf_puthdr(efd, pid, map, hdr, hdrsize, notesz, segoff, seginfo.count); n = write(fd, hdr, segoff); if (n == -1) @@ -412,12 +412,19 @@ elf_putnote(int type, notefunc_t notefunc, void *arg, struct sbuf *sb) * Generate the ELF coredump header. */ static void -elf_puthdr(pid_t pid, vm_map_entry_t map, void *hdr, size_t hdrsize, +elf_puthdr(int efd, pid_t pid, vm_map_entry_t map, void *hdr, size_t hdrsize, size_t notesz, size_t segoff, int numsegs) { - Elf_Ehdr *ehdr; + Elf_Ehdr *ehdr, binhdr; Elf_Phdr *phdr; struct phdr_closure phc; + ssize_t cnt; + + cnt = read(efd, &binhdr, sizeof(binhdr)); + if (cnt < 0) + err(1, "Failed to re-read ELF header"); + else if (cnt != sizeof(binhdr)) + errx(1, "Failed to re-read ELF header"); ehdr = (Elf_Ehdr *)hdr; phdr = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)); @@ -433,11 +440,11 @@ elf_puthdr(pid_t pid, vm_map_entry_t map, void *hdr, size_t hdrsize, ehdr->e_ident[EI_ABIVERSION] = 0; ehdr->e_ident[EI_PAD] = 0; ehdr->e_type = ET_CORE; - ehdr->e_machine = ELF_ARCH; + ehdr->e_machine = binhdr.e_machine; ehdr->e_version = EV_CURRENT; ehdr->e_entry = 0; ehdr->e_phoff = sizeof(Elf_Ehdr); - ehdr->e_flags = 0; + ehdr->e_flags = binhdr.e_flags; ehdr->e_ehsize = sizeof(Elf_Ehdr); ehdr->e_phentsize = sizeof(Elf_Phdr); ehdr->e_phnum = numsegs + 1; -- 2.45.0