diff options
| -rw-r--r-- | sys/kern/imgact_elf.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c index a9ee58d941c4..c27d61e81ed4 100644 --- a/sys/kern/imgact_elf.c +++ b/sys/kern/imgact_elf.c @@ -1584,6 +1584,8 @@ typedef void (*segment_callback)(vm_map_entry_t, void *); struct phdr_closure { Elf_Phdr *phdr; /* Program header to fill in */ Elf_Off offset; /* Offset of segment in core file */ + int numsegs; /* Maximum number of segments */ + int nextseg; /* Next segment to fill in */ }; struct note_info { @@ -1700,10 +1702,15 @@ __elfN(coredump)(struct thread *td, struct coredump_writer *cdw, off_t limit, in } /* - * Allocate memory for building the header, fill it up, - * and write it out following the notes. + * Allocate memory for building the header, fill it up, and write it out + * following the notes. + * + * Note that a process sharing our vmspace might be concurrently + * mutating the map, in which case we could populate fewer than + * seginfo.count headers. Zero the buffer to ensure that unpopulated + * headers are still initialized. */ - hdr = malloc(hdrsize, M_TEMP, M_WAITOK); + hdr = malloc(hdrsize, M_TEMP, M_WAITOK | M_ZERO); error = __elfN(corehdr)(¶ms, seginfo.count, hdr, hdrsize, ¬elst, notesz, flags); @@ -1756,6 +1763,11 @@ cb_put_phdr(vm_map_entry_t entry, void *closure) struct phdr_closure *phc = (struct phdr_closure *)closure; Elf_Phdr *phdr = phc->phdr; + if (phc->nextseg >= phc->numsegs) { + /* Only write as many headers as we have space for. */ + return; + } + phc->offset = round_page(phc->offset); phdr->p_type = PT_LOAD; @@ -1768,6 +1780,8 @@ cb_put_phdr(vm_map_entry_t entry, void *closure) phc->offset += phdr->p_filesz; phc->phdr++; + + phc->nextseg++; } /* @@ -2030,6 +2044,8 @@ __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs, /* All the writable segments from the program. */ phc.phdr = phdr; phc.offset = round_page(hdrsize + notesz); + phc.numsegs = numsegs; + phc.nextseg = 0; each_dumpable_segment(td, cb_put_phdr, &phc, flags); } |