| Message ID | 20190610212015.9157-8-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/15] binfmt_flat: remove flat_reloc_valid | expand |
Hi Christoph, On Mon, Jun 10, 2019 at 11:21 PM Christoph Hellwig <hch@lst.de> wrote: > So far binfmt_flat has onl been supported on 32-bit platforms, so the > variable size of the fields didn't matter. But the upcoming RISC-V > nommu port supports 64-bit CPUs, and we now have a conflict between > the elf2flt creation tool that always uses 32-bit fields and the kernel > that uses (unsigned) long field. Switch to the userspace view as the > rest of the binfmt_flat format is completely architecture neutral, > and binfmt_flat isn't the right binary format for huge executables to > start with. > > While we're at it also ensure these fields are using __be types as > they big endian and are byteswapped when loaded. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- a/include/linux/flat.h > +++ b/include/linux/flat.h > @@ -67,19 +67,19 @@ struct flat_hdr { > #define OLD_FLAT_RELOC_TYPE_BSS 2 > > typedef union { > - unsigned long value; > + u32 value; > struct { > # if defined(mc68000) && !defined(CONFIG_COLDFIRE) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__BIG_ENDIAN_BITFIELD) > - unsigned long type : 2; > - signed long offset : 30; > + u32 type : 2; > + s32 offset : 30; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__LITTLE_ENDIAN_BITFIELD) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ The definitions of OLD_FLAT_FLAG_RAM are identical, so could be factored out. However, they appear to be unused. > # else > # error "Unknown bitfield order for flat files." Gr{oetje,eeting}s, Geert
On 6/10/19 10:20 PM, Christoph Hellwig wrote: > So far binfmt_flat has onl been supported on 32-bit platforms, so the ^^^^ only > variable size of the fields didn't matter. But the upcoming RISC-V > nommu port supports 64-bit CPUs, and we now have a conflict between > the elf2flt creation tool that always uses 32-bit fields and the kernel > that uses (unsigned) long field. Switch to the userspace view as the > rest of the binfmt_flat format is completely architecture neutral, > and binfmt_flat isn't the right binary format for huge executables to > start with. > > While we're at it also ensure these fields are using __be types as > they big endian and are byteswapped when loaded. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > > wip ^^^ Unintended? > --- > include/linux/flat.h | 48 ++++++++++++++++++++++---------------------- > 1 file changed, 24 insertions(+), 24 deletions(-) With comment message fixed: Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com> > > diff --git a/include/linux/flat.h b/include/linux/flat.h > index 21d901ba191b..59e892d5fadb 100644 > --- a/include/linux/flat.h > +++ b/include/linux/flat.h > @@ -24,26 +24,26 @@ > */ > > struct flat_hdr { > - char magic[4]; > - unsigned long rev; /* version (as above) */ > - unsigned long entry; /* Offset of first executable instruction > - with text segment from beginning of file */ > - unsigned long data_start; /* Offset of data segment from beginning of > - file */ > - unsigned long data_end; /* Offset of end of data segment > - from beginning of file */ > - unsigned long bss_end; /* Offset of end of bss segment from beginning > - of file */ > + char magic[4]; > + __be32 rev; /* version (as above) */ > + __be32 entry; /* Offset of first executable instruction > + with text segment from beginning of file */ > + __be32 data_start; /* Offset of data segment from beginning of > + file */ > + __be32 data_end; /* Offset of end of data segment from beginning > + of file */ > + __be32 bss_end; /* Offset of end of bss segment from beginning > + of file */ > > /* (It is assumed that data_end through bss_end forms the bss segment.) */ > > - unsigned long stack_size; /* Size of stack, in bytes */ > - unsigned long reloc_start; /* Offset of relocation records from > - beginning of file */ > - unsigned long reloc_count; /* Number of relocation records */ > - unsigned long flags; > - unsigned long build_date; /* When the program/library was built */ > - unsigned long filler[5]; /* Reservered, set to zero */ > + __be32 stack_size; /* Size of stack, in bytes */ > + __be32 reloc_start; /* Offset of relocation records from beginning of > + file */ > + __be32 reloc_count; /* Number of relocation records */ > + __be32 flags; > + __be32 build_date; /* When the program/library was built */ > + __u32 filler[5]; /* Reservered, set to zero */ > }; > > #define FLAT_FLAG_RAM 0x0001 /* load program entirely into RAM */ > @@ -67,19 +67,19 @@ struct flat_hdr { > #define OLD_FLAT_RELOC_TYPE_BSS 2 > > typedef union { > - unsigned long value; > + u32 value; > struct { > # if defined(mc68000) && !defined(CONFIG_COLDFIRE) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__BIG_ENDIAN_BITFIELD) > - unsigned long type : 2; > - signed long offset : 30; > + u32 type : 2; > + s32 offset : 30; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # elif defined(__LITTLE_ENDIAN_BITFIELD) > - signed long offset : 30; > - unsigned long type : 2; > + s32 offset : 30; > + u32 type : 2; > # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ > # else > # error "Unknown bitfield order for flat files." >
diff --git a/include/linux/flat.h b/include/linux/flat.h index 21d901ba191b..59e892d5fadb 100644 --- a/include/linux/flat.h +++ b/include/linux/flat.h @@ -24,26 +24,26 @@ */ struct flat_hdr { - char magic[4]; - unsigned long rev; /* version (as above) */ - unsigned long entry; /* Offset of first executable instruction - with text segment from beginning of file */ - unsigned long data_start; /* Offset of data segment from beginning of - file */ - unsigned long data_end; /* Offset of end of data segment - from beginning of file */ - unsigned long bss_end; /* Offset of end of bss segment from beginning - of file */ + char magic[4]; + __be32 rev; /* version (as above) */ + __be32 entry; /* Offset of first executable instruction + with text segment from beginning of file */ + __be32 data_start; /* Offset of data segment from beginning of + file */ + __be32 data_end; /* Offset of end of data segment from beginning + of file */ + __be32 bss_end; /* Offset of end of bss segment from beginning + of file */ /* (It is assumed that data_end through bss_end forms the bss segment.) */ - unsigned long stack_size; /* Size of stack, in bytes */ - unsigned long reloc_start; /* Offset of relocation records from - beginning of file */ - unsigned long reloc_count; /* Number of relocation records */ - unsigned long flags; - unsigned long build_date; /* When the program/library was built */ - unsigned long filler[5]; /* Reservered, set to zero */ + __be32 stack_size; /* Size of stack, in bytes */ + __be32 reloc_start; /* Offset of relocation records from beginning of + file */ + __be32 reloc_count; /* Number of relocation records */ + __be32 flags; + __be32 build_date; /* When the program/library was built */ + __u32 filler[5]; /* Reservered, set to zero */ }; #define FLAT_FLAG_RAM 0x0001 /* load program entirely into RAM */ @@ -67,19 +67,19 @@ struct flat_hdr { #define OLD_FLAT_RELOC_TYPE_BSS 2 typedef union { - unsigned long value; + u32 value; struct { # if defined(mc68000) && !defined(CONFIG_COLDFIRE) - signed long offset : 30; - unsigned long type : 2; + s32 offset : 30; + u32 type : 2; # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ # elif defined(__BIG_ENDIAN_BITFIELD) - unsigned long type : 2; - signed long offset : 30; + u32 type : 2; + s32 offset : 30; # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ # elif defined(__LITTLE_ENDIAN_BITFIELD) - signed long offset : 30; - unsigned long type : 2; + s32 offset : 30; + u32 type : 2; # define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */ # else # error "Unknown bitfield order for flat files."
So far binfmt_flat has onl been supported on 32-bit platforms, so the variable size of the fields didn't matter. But the upcoming RISC-V nommu port supports 64-bit CPUs, and we now have a conflict between the elf2flt creation tool that always uses 32-bit fields and the kernel that uses (unsigned) long field. Switch to the userspace view as the rest of the binfmt_flat format is completely architecture neutral, and binfmt_flat isn't the right binary format for huge executables to start with. While we're at it also ensure these fields are using __be types as they big endian and are byteswapped when loaded. Signed-off-by: Christoph Hellwig <hch@lst.de> wip --- include/linux/flat.h | 48 ++++++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 24 deletions(-)