On Thu, 10 Oct 2024 at 22:34, Josh Poimboeuf wrote:
>
> On Thu, Oct 10, 2024 at 02:28:07PM +0200, Ard Biesheuvel wrote:
> > From: Ard Biesheuvel
> >
> > Tweak the jump table so
> > - the address is taken far way from its use
> > - its offset from the start of .rodata is != 0x0
> > - its type is S
On Thu, 10 Oct 2024 at 22:15, Josh Poimboeuf wrote:
>
> On Thu, Oct 10, 2024 at 02:28:05PM +0200, Ard Biesheuvel wrote:
> > +++ b/tools/objtool/arch/x86/special.c
> > @@ -115,30 +115,51 @@ struct reloc *arch_find_switch_table(struct
> > objtool_file *file,
> > struct reloc *text_reloc, *ro
On Tue, Oct 8, 2024 at 5:42 PM Liam R. Howlett wrote:
>
> * Jeff Xu [241008 11:01]:
> > Hi Liam,
> >
> > On Mon, Oct 7, 2024 at 7:19 PM Liam R. Howlett
> > wrote:
> > >
> > > * jef...@chromium.org [241004 12:32]:
> > > > From: Jeff Xu
> > > >
> > > > Seal vdso, vvar, sigpage, uprobes and vsys
On Tue, Oct 8, 2024 at 9:37 AM Randy Dunlap wrote:
>
>
>
> On 10/7/24 9:18 PM, jef...@chromium.org wrote:
> > From: Jeff Xu
> >
> > Change "overwrite" to overwrites"
> >
> > Signed-off-by: Jeff Xu
> > ---
> > Documentation/userspace-api/mseal.rst | 2 +-
> > 1 file changed, 1 insertion(+), 1 de
On Thu, Oct 10, 2024 at 07:50:17PM +0200, Ard Biesheuvel wrote:
> On Thu, 10 Oct 2024 at 14:28, Ard Biesheuvel wrote:
> >
> > From: Ard Biesheuvel
> >
> > Jump table handling has faded into the background a little due to the
> > fact that jump tables are [currently] disabled when enabling retpoli
On Thu, Oct 10, 2024 at 02:28:07PM +0200, Ard Biesheuvel wrote:
> From: Ard Biesheuvel
>
> Tweak the jump table so
> - the address is taken far way from its use
> - its offset from the start of .rodata is != 0x0
> - its type is STT_OBJECT and its size is set to the size of the actual
> table
>
On Thu, Oct 10, 2024 at 02:28:05PM +0200, Ard Biesheuvel wrote:
> +++ b/tools/objtool/arch/x86/special.c
> @@ -115,30 +115,51 @@ struct reloc *arch_find_switch_table(struct
> objtool_file *file,
> struct reloc *text_reloc, *rodata_reloc;
> struct section *table_sec;
> unsigned l
On Thu, Oct 10, 2024 at 02:28:05PM +0200, Ard Biesheuvel wrote:
> @@ -1394,8 +1396,12 @@ static struct reloc *insn_reloc(struct objtool_file
> *file, struct instruction *i
> if (!file)
> return NULL;
>
> - reloc = find_reloc_by_dest_range(file->elf, insn->sec,
> -
On Thu, Oct 10, 2024 at 02:28:04PM +0200, Ard Biesheuvel wrote:
> @@ -,7 +2234,6 @@ static void mark_func_jump_tables(struct objtool_file
> *file,
> struct symbol *func)
> {
> struct instruction *insn, *last = NULL;
> - struct reloc *reloc;
>
>
On Thu, 10 Oct 2024 at 14:28, Ard Biesheuvel wrote:
>
> From: Ard Biesheuvel
>
> Jump table handling has faded into the background a little due to the
> fact that jump tables are [currently] disabled when enabling retpoline
> mitigations and/or IBT on x86.
>
> However, this is likely to come back
On Thu, Oct 10, 2024 at 04:07:45PM +0200, Peter Zijlstra wrote:
> On Thu, Oct 10, 2024 at 03:59:43PM +0200, Ard Biesheuvel wrote:
> > On Thu, 10 Oct 2024 at 15:26, Peter Zijlstra wrote:
> > >
> > > On Thu, Oct 10, 2024 at 02:28:03PM +0200, Ard Biesheuvel wrote:
> > > > diff --git a/tools/objtool/c
On Thu, Oct 10, 2024 at 03:59:43PM +0200, Ard Biesheuvel wrote:
> On Thu, 10 Oct 2024 at 15:26, Peter Zijlstra wrote:
> >
> > On Thu, Oct 10, 2024 at 02:28:03PM +0200, Ard Biesheuvel wrote:
> > > diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> > > index 3cb3e9b5ad0b..7f7981a93535 1006
On Thu, 10 Oct 2024 at 15:26, Peter Zijlstra wrote:
>
> On Thu, Oct 10, 2024 at 02:28:03PM +0200, Ard Biesheuvel wrote:
> > diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> > index 3cb3e9b5ad0b..7f7981a93535 100644
> > --- a/tools/objtool/check.c
> > +++ b/tools/objtool/check.c
> > @@
On Thu, Oct 10, 2024 at 02:28:03PM +0200, Ard Biesheuvel wrote:
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 3cb3e9b5ad0b..7f7981a93535 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -2101,6 +2101,8 @@ static int add_jump_table(struct objtool_file *f
From: Ard Biesheuvel
Tweak the jump table so
- the address is taken far way from its use
- its offset from the start of .rodata is != 0x0
- its type is STT_OBJECT and its size is set to the size of the actual
table
- the indirect jump is annotated with a R_X86_64_NONE relocation
pointing to t
From: Ard Biesheuvel
The original crc32c code used a place-relative jump table but with a
slightly awkward use of two separate symbols. To help objtool, this was
replaced with a bog-standard position dependent jump table call, which
was subsequently tweaked to use a RIP-relative reference to the
From: Ard Biesheuvel
Add logic to follow R_X86_64_NONE relocations attached to indirect
jumps, which are emitted to annotate jump tables, which are otherwise
difficult to spot reliably.
If an ELF symbol is associated with the jump table, its size is taken as
the size of the jump table, and subse
From: Ard Biesheuvel
In preparation for adding support for annotated jump tables, where
ELF relocations and symbols are used to describe the locations of jump
tables in the executable, refactor the jump table discovery logic so the
table size can be returned from arch_find_switch_table().
Signed
From: Ard Biesheuvel
Relative jump tables contain entries that carry the offset between the
target of the jump and the start of the jump table. This permits the use
of the PIC idiom of
leaqjump_table(%rip), %tbl
movslq (%tbl,%idx,4), %offset
addq%offset, %tbl
jmp *%t
From: Ard Biesheuvel
Jump table handling has faded into the background a little due to the
fact that jump tables are [currently] disabled when enabling retpoline
mitigations and/or IBT on x86.
However, this is likely to come back and bite us later, so it still
needs to be addressed. Given the di
21 matches
Mail list logo
