| Message ID | 20210110115245.30762-1-alobakin@pm.me |
|---|---|
| Headers | show |
| Series | MIPS: vmlinux.lds.S sections fixes & cleanup | expand |
On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: > This series hunts the problems discovered after manual enabling of > ARCH_WANT_LD_ORPHAN_WARN. Notably: > - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO > placement (marked for stable); > - stops blind catching of orphan text sections with .text.* > directive; > - properly stops .eh_frame section generation. > > Compile and runtime tested on MIPS32R2 CPS board with no issues > using two different toolkits: > - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches); > - LLVM stack: 11.0.0 and from latest Git snapshot. > > Since v4 [3]: > - new: drop redundant .text.cps-vec creation and blind inclusion > of orphan text sections via .text.* directive in vmlinux.lds.S; > - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not > empty on certain machines and compilers (Thomas); > - align GOT table like it's done for ARM64; > - new: catch UBSAN's "unnamed data" sections in generic definitions > when building with LD_DEAD_CODE_DATA_ELIMINATION; > - collect Reviewed-bys (Kees, Nathan). Looks good; which tree will this land through? -Kees > > Since v3 [2]: > - fix the third patch as GNU stack emits .rel.dyn into VDSO for > some reason if .cfi_sections is specified. > > Since v2 [1]: > - stop discarding .eh_frame and just prevent it from generating > (Kees); > - drop redundant sections assertions (Fangrui); > - place GOT table in .text instead of asserting as it's not empty > when building with LLVM (Nathan); > - catch compound literals in generic definitions when building with > LD_DEAD_CODE_DATA_ELIMINATION (Kees); > - collect two Reviewed-bys (Kees). > > Since v1 [0]: > - catch .got entries too as LLD may produce it (Nathan); > - check for unwanted sections to be zero-sized instead of > discarding (Fangrui). > > [0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me > [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me > [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me > [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me > > Alexander Lobakin (9): > MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section > MIPS: CPS: don't create redundant .text.cps-vec section > MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS > MIPS: properly stop .eh_frame generation > MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols > MIPS: vmlinux.lds.S: explicitly declare .got table > vmlinux.lds.h: catch compound literals into data and BSS > vmlinux.lds.h: catch UBSAN's "unnamed data" into data > MIPS: select ARCH_WANT_LD_ORPHAN_WARN > > arch/mips/Kconfig | 1 + > arch/mips/include/asm/asm.h | 18 ++++++++++++++++++ > arch/mips/kernel/cps-vec.S | 1 - > arch/mips/kernel/vmlinux.lds.S | 11 +++++++++-- > include/asm-generic/vmlinux.lds.h | 6 +++--- > 5 files changed, 31 insertions(+), 6 deletions(-) > > -- > 2.30.0 > >
From: Kees Cook <keescook@chromium.org> Date: Mon, 11 Jan 2021 11:53:39 -0800 > On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: >> This series hunts the problems discovered after manual enabling of >> ARCH_WANT_LD_ORPHAN_WARN. Notably: >> - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO >> placement (marked for stable); >> - stops blind catching of orphan text sections with .text.* >> directive; >> - properly stops .eh_frame section generation. >> >> Compile and runtime tested on MIPS32R2 CPS board with no issues >> using two different toolkits: >> - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches); >> - LLVM stack: 11.0.0 and from latest Git snapshot. >> >> Since v4 [3]: >> - new: drop redundant .text.cps-vec creation and blind inclusion >> of orphan text sections via .text.* directive in vmlinux.lds.S; >> - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not >> empty on certain machines and compilers (Thomas); >> - align GOT table like it's done for ARM64; >> - new: catch UBSAN's "unnamed data" sections in generic definitions >> when building with LD_DEAD_CODE_DATA_ELIMINATION; >> - collect Reviewed-bys (Kees, Nathan). > > Looks good; which tree will this land through? linux-mips/mips-next I guess, since 7 of 9 patches are related only to this architecture. This might need Arnd's Acked-bys or Reviewed-by for the two that refer include/asm-generic, let's see what Thomas think. > -Kees > >> >> Since v3 [2]: >> - fix the third patch as GNU stack emits .rel.dyn into VDSO for >> some reason if .cfi_sections is specified. >> >> Since v2 [1]: >> - stop discarding .eh_frame and just prevent it from generating >> (Kees); >> - drop redundant sections assertions (Fangrui); >> - place GOT table in .text instead of asserting as it's not empty >> when building with LLVM (Nathan); >> - catch compound literals in generic definitions when building with >> LD_DEAD_CODE_DATA_ELIMINATION (Kees); >> - collect two Reviewed-bys (Kees). >> >> Since v1 [0]: >> - catch .got entries too as LLD may produce it (Nathan); >> - check for unwanted sections to be zero-sized instead of >> discarding (Fangrui). >> >> [0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me >> [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me >> [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me >> [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me >> >> Alexander Lobakin (9): >> MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section >> MIPS: CPS: don't create redundant .text.cps-vec section >> MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS >> MIPS: properly stop .eh_frame generation >> MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols >> MIPS: vmlinux.lds.S: explicitly declare .got table >> vmlinux.lds.h: catch compound literals into data and BSS >> vmlinux.lds.h: catch UBSAN's "unnamed data" into data >> MIPS: select ARCH_WANT_LD_ORPHAN_WARN >> >> arch/mips/Kconfig | 1 + >> arch/mips/include/asm/asm.h | 18 ++++++++++++++++++ >> arch/mips/kernel/cps-vec.S | 1 - >> arch/mips/kernel/vmlinux.lds.S | 11 +++++++++-- >> include/asm-generic/vmlinux.lds.h | 6 +++--- >> 5 files changed, 31 insertions(+), 6 deletions(-) >> >> -- >> 2.30.0 >> >> > > -- > Kees Cook Al
On Mon, Jan 11, 2021 at 11:44 PM Thomas Bogendoerfer <tsbogend@alpha.franken.de> wrote: > On Mon, Jan 11, 2021 at 08:57:25PM +0000, Alexander Lobakin wrote: > > From: Kees Cook <keescook@chromium.org> > > Date: Mon, 11 Jan 2021 11:53:39 -0800 > > > > > On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: > > >> This series hunts the problems discovered after manual enabling of > > >> ARCH_WANT_LD_ORPHAN_WARN. Notably: > > >> - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO > > >> placement (marked for stable); > > >> - stops blind catching of orphan text sections with .text.* > > >> directive; > > >> - properly stops .eh_frame section generation. > > >> > > >> Compile and runtime tested on MIPS32R2 CPS board with no issues > > >> using two different toolkits: > > >> - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches); > > >> - LLVM stack: 11.0.0 and from latest Git snapshot. > > >> > > >> Since v4 [3]: > > >> - new: drop redundant .text.cps-vec creation and blind inclusion > > >> of orphan text sections via .text.* directive in vmlinux.lds.S; > > >> - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not > > >> empty on certain machines and compilers (Thomas); > > >> - align GOT table like it's done for ARM64; > > >> - new: catch UBSAN's "unnamed data" sections in generic definitions > > >> when building with LD_DEAD_CODE_DATA_ELIMINATION; > > >> - collect Reviewed-bys (Kees, Nathan). > > > > > > Looks good; which tree will this land through? > > > > linux-mips/mips-next I guess, since 7 of 9 patches are related only > > to this architecture. > > This might need Arnd's Acked-bys or Reviewed-by for the two that > > refer include/asm-generic, let's see what Thomas think. > > Looks good from my side and I have it already sitting in branch for > submission. > > Arnd, are you ok with the changes in include/asm-generic ? Yes, I'm never quite sure about what to make of linker script changes, but I trust Kees on the review. For merging it through your tree: Acked-by: Arnd Bergmann <arnd@arndb.de>
On Sun, Jan 10, 2021 at 11:53:50AM +0000, Alexander Lobakin wrote: > This series hunts the problems discovered after manual enabling of > ARCH_WANT_LD_ORPHAN_WARN. Notably: > - adds the missing PAGE_ALIGNED_DATA() section affecting VDSO > placement (marked for stable); > - stops blind catching of orphan text sections with .text.* > directive; > - properly stops .eh_frame section generation. > > Compile and runtime tested on MIPS32R2 CPS board with no issues > using two different toolkits: > - Binutils 2.35.1, GCC 10.2.1 (with Alpine patches); > - LLVM stack: 11.0.0 and from latest Git snapshot. > > Since v4 [3]: > - new: drop redundant .text.cps-vec creation and blind inclusion > of orphan text sections via .text.* directive in vmlinux.lds.S; > - don't assert SIZEOF(.rel.dyn) as it's reported that it may be not > empty on certain machines and compilers (Thomas); > - align GOT table like it's done for ARM64; > - new: catch UBSAN's "unnamed data" sections in generic definitions > when building with LD_DEAD_CODE_DATA_ELIMINATION; > - collect Reviewed-bys (Kees, Nathan). > > Since v3 [2]: > - fix the third patch as GNU stack emits .rel.dyn into VDSO for > some reason if .cfi_sections is specified. > > Since v2 [1]: > - stop discarding .eh_frame and just prevent it from generating > (Kees); > - drop redundant sections assertions (Fangrui); > - place GOT table in .text instead of asserting as it's not empty > when building with LLVM (Nathan); > - catch compound literals in generic definitions when building with > LD_DEAD_CODE_DATA_ELIMINATION (Kees); > - collect two Reviewed-bys (Kees). > > Since v1 [0]: > - catch .got entries too as LLD may produce it (Nathan); > - check for unwanted sections to be zero-sized instead of > discarding (Fangrui). > > [0] https://lore.kernel.org/linux-mips/20210104121729.46981-1-alobakin@pm.me > [1] https://lore.kernel.org/linux-mips/20210106200713.31840-1-alobakin@pm.me > [2] https://lore.kernel.org/linux-mips/20210107115120.281008-1-alobakin@pm.me > [3] https://lore.kernel.org/linux-mips/20210107123331.354075-1-alobakin@pm.me > > Alexander Lobakin (9): > MIPS: vmlinux.lds.S: add missing PAGE_ALIGNED_DATA() section > MIPS: CPS: don't create redundant .text.cps-vec section > MIPS: vmlinux.lds.S: add ".gnu.attributes" to DISCARDS > MIPS: properly stop .eh_frame generation > MIPS: vmlinux.lds.S: explicitly catch .rel.dyn symbols > MIPS: vmlinux.lds.S: explicitly declare .got table > vmlinux.lds.h: catch compound literals into data and BSS > vmlinux.lds.h: catch UBSAN's "unnamed data" into data > MIPS: select ARCH_WANT_LD_ORPHAN_WARN > > arch/mips/Kconfig | 1 + > arch/mips/include/asm/asm.h | 18 ++++++++++++++++++ > arch/mips/kernel/cps-vec.S | 1 - > arch/mips/kernel/vmlinux.lds.S | 11 +++++++++-- > include/asm-generic/vmlinux.lds.h | 6 +++--- > 5 files changed, 31 insertions(+), 6 deletions(-) applied to mips-next. Thoomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]