| Message ID | 20220301142213.28568-4-frankja@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | dump: Cleanup and consolidation | expand |
On Tue, Mar 1, 2022 at 6:22 PM Janosch Frank <frankja@linux.ibm.com> wrote: > > Offset calculations are easy enough to get wrong. Let's add a few > variables to make moving around elf headers and data sections easier. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > dump/dump.c | 34 ++++++++++++++-------------------- > include/sysemu/dump.h | 4 ++++ > 2 files changed, 18 insertions(+), 20 deletions(-) > > diff --git a/dump/dump.c b/dump/dump.c > index ce3a5e7003..242f83db95 100644 > --- a/dump/dump.c > +++ b/dump/dump.c > @@ -137,13 +137,11 @@ static void write_elf64_header(DumpState *s, Error **errp) > elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine); > elf_header.e_version = cpu_to_dump32(s, EV_CURRENT); > elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); > - elf_header.e_phoff = cpu_to_dump64(s, sizeof(Elf64_Ehdr)); > + elf_header.e_phoff = cpu_to_dump64(s, s->phdr_offset); > elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); > elf_header.e_phnum = cpu_to_dump16(s, phnum); > if (s->shdr_num) { > - uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->phdr_num; > - > - elf_header.e_shoff = cpu_to_dump64(s, shoff); > + elf_header.e_shoff = cpu_to_dump64(s, s->shdr_offset); > elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); > elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num); > } > @@ -169,13 +167,11 @@ static void write_elf32_header(DumpState *s, Error **errp) > elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine); > elf_header.e_version = cpu_to_dump32(s, EV_CURRENT); > elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); > - elf_header.e_phoff = cpu_to_dump32(s, sizeof(Elf32_Ehdr)); > + elf_header.e_phoff = cpu_to_dump32(s, s->phdr_offset); > elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); > elf_header.e_phnum = cpu_to_dump16(s, phnum); > if (s->shdr_num) { > - uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->phdr_num; > - > - elf_header.e_shoff = cpu_to_dump32(s, shoff); > + elf_header.e_shoff = cpu_to_dump32(s, s->shdr_offset); > elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); > elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num); > } > @@ -238,12 +234,11 @@ static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, > static void write_elf64_note(DumpState *s, Error **errp) > { > Elf64_Phdr phdr; > - hwaddr begin = s->memory_offset - s->note_size; > int ret; > > memset(&phdr, 0, sizeof(Elf64_Phdr)); > phdr.p_type = cpu_to_dump32(s, PT_NOTE); > - phdr.p_offset = cpu_to_dump64(s, begin); > + phdr.p_offset = cpu_to_dump64(s, s->note_offset); > phdr.p_paddr = 0; > phdr.p_filesz = cpu_to_dump64(s, s->note_size); > phdr.p_memsz = cpu_to_dump64(s, s->note_size); > @@ -303,13 +298,12 @@ static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, > > static void write_elf32_note(DumpState *s, Error **errp) > { > - hwaddr begin = s->memory_offset - s->note_size; > Elf32_Phdr phdr; > int ret; > > memset(&phdr, 0, sizeof(Elf32_Phdr)); > phdr.p_type = cpu_to_dump32(s, PT_NOTE); > - phdr.p_offset = cpu_to_dump32(s, begin); > + phdr.p_offset = cpu_to_dump32(s, s->note_offset); > phdr.p_paddr = 0; > phdr.p_filesz = cpu_to_dump32(s, s->note_size); > phdr.p_memsz = cpu_to_dump32(s, s->note_size); > @@ -1828,15 +1822,15 @@ static void dump_init(DumpState *s, int fd, bool has_format, > } > > if (s->dump_info.d_class == ELFCLASS64) { > - s->memory_offset = sizeof(Elf64_Ehdr) + > - sizeof(Elf64_Phdr) * s->phdr_num + > - sizeof(Elf64_Shdr) * s->shdr_num + > - s->note_size; > + s->phdr_offset = sizeof(Elf64_Ehdr); > + s->shdr_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; > + s->note_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; > + s->memory_offset = s->note_offset + s->note_size; > } else { > - s->memory_offset = sizeof(Elf32_Ehdr) + > - sizeof(Elf32_Phdr) * s->phdr_num + > - sizeof(Elf32_Shdr) * s->shdr_num + > - s->note_size; > + s->phdr_offset = sizeof(Elf32_Ehdr); > + s->shdr_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; > + s->note_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; > + s->memory_offset = s->note_offset + s->note_size; > } > > return; > diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h > index 19458bffbd..ffc2ea1072 100644 > --- a/include/sysemu/dump.h > +++ b/include/sysemu/dump.h > @@ -159,6 +159,10 @@ typedef struct DumpState { > bool resume; > bool detached; > ssize_t note_size; > + hwaddr shdr_offset; > + hwaddr phdr_offset; > + hwaddr section_offset; > + hwaddr note_offset; > hwaddr memory_offset; > int fd; > > -- > 2.32.0 >
diff --git a/dump/dump.c b/dump/dump.c index ce3a5e7003..242f83db95 100644 --- a/dump/dump.c +++ b/dump/dump.c @@ -137,13 +137,11 @@ static void write_elf64_header(DumpState *s, Error **errp) elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine); elf_header.e_version = cpu_to_dump32(s, EV_CURRENT); elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); - elf_header.e_phoff = cpu_to_dump64(s, sizeof(Elf64_Ehdr)); + elf_header.e_phoff = cpu_to_dump64(s, s->phdr_offset); elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr)); elf_header.e_phnum = cpu_to_dump16(s, phnum); if (s->shdr_num) { - uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->phdr_num; - - elf_header.e_shoff = cpu_to_dump64(s, shoff); + elf_header.e_shoff = cpu_to_dump64(s, s->shdr_offset); elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr)); elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num); } @@ -169,13 +167,11 @@ static void write_elf32_header(DumpState *s, Error **errp) elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine); elf_header.e_version = cpu_to_dump32(s, EV_CURRENT); elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header)); - elf_header.e_phoff = cpu_to_dump32(s, sizeof(Elf32_Ehdr)); + elf_header.e_phoff = cpu_to_dump32(s, s->phdr_offset); elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr)); elf_header.e_phnum = cpu_to_dump16(s, phnum); if (s->shdr_num) { - uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->phdr_num; - - elf_header.e_shoff = cpu_to_dump32(s, shoff); + elf_header.e_shoff = cpu_to_dump32(s, s->shdr_offset); elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr)); elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num); } @@ -238,12 +234,11 @@ static void write_elf32_load(DumpState *s, MemoryMapping *memory_mapping, static void write_elf64_note(DumpState *s, Error **errp) { Elf64_Phdr phdr; - hwaddr begin = s->memory_offset - s->note_size; int ret; memset(&phdr, 0, sizeof(Elf64_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_NOTE); - phdr.p_offset = cpu_to_dump64(s, begin); + phdr.p_offset = cpu_to_dump64(s, s->note_offset); phdr.p_paddr = 0; phdr.p_filesz = cpu_to_dump64(s, s->note_size); phdr.p_memsz = cpu_to_dump64(s, s->note_size); @@ -303,13 +298,12 @@ static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, static void write_elf32_note(DumpState *s, Error **errp) { - hwaddr begin = s->memory_offset - s->note_size; Elf32_Phdr phdr; int ret; memset(&phdr, 0, sizeof(Elf32_Phdr)); phdr.p_type = cpu_to_dump32(s, PT_NOTE); - phdr.p_offset = cpu_to_dump32(s, begin); + phdr.p_offset = cpu_to_dump32(s, s->note_offset); phdr.p_paddr = 0; phdr.p_filesz = cpu_to_dump32(s, s->note_size); phdr.p_memsz = cpu_to_dump32(s, s->note_size); @@ -1828,15 +1822,15 @@ static void dump_init(DumpState *s, int fd, bool has_format, } if (s->dump_info.d_class == ELFCLASS64) { - s->memory_offset = sizeof(Elf64_Ehdr) + - sizeof(Elf64_Phdr) * s->phdr_num + - sizeof(Elf64_Shdr) * s->shdr_num + - s->note_size; + s->phdr_offset = sizeof(Elf64_Ehdr); + s->shdr_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num; + s->note_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num; + s->memory_offset = s->note_offset + s->note_size; } else { - s->memory_offset = sizeof(Elf32_Ehdr) + - sizeof(Elf32_Phdr) * s->phdr_num + - sizeof(Elf32_Shdr) * s->shdr_num + - s->note_size; + s->phdr_offset = sizeof(Elf32_Ehdr); + s->shdr_offset = s->phdr_offset + sizeof(Elf32_Phdr) * s->phdr_num; + s->note_offset = s->shdr_offset + sizeof(Elf32_Shdr) * s->shdr_num; + s->memory_offset = s->note_offset + s->note_size; } return; diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h index 19458bffbd..ffc2ea1072 100644 --- a/include/sysemu/dump.h +++ b/include/sysemu/dump.h @@ -159,6 +159,10 @@ typedef struct DumpState { bool resume; bool detached; ssize_t note_size; + hwaddr shdr_offset; + hwaddr phdr_offset; + hwaddr section_offset; + hwaddr note_offset; hwaddr memory_offset; int fd;
Offset calculations are easy enough to get wrong. Let's add a few variables to make moving around elf headers and data sections easier. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> --- dump/dump.c | 34 ++++++++++++++-------------------- include/sysemu/dump.h | 4 ++++ 2 files changed, 18 insertions(+), 20 deletions(-)