| Message ID | 20200306044852.3236-1-cai@lca.pw (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | c2e929b18cea6cbf71364f22d742d9aad7f4677a |
| Headers | show |
| Series | [v3] powerpc/64s/pgtable: fix an undefined behaviour | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (ab326587bb5fb91cc97df9b9f48e9e1469f04621) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 29 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
Le 06/03/2020 à 05:48, Qian Cai a écrit : > Booting a power9 server with hash MMU could trigger an undefined > behaviour because pud_offset(p4d, 0) will do, > > 0 >> (PAGE_SHIFT:16 + PTE_INDEX_SIZE:8 + H_PMD_INDEX_SIZE:10) > > Fix it by converting pud_index() and friends to static inline > functions. > > UBSAN: shift-out-of-bounds in arch/powerpc/mm/ptdump/ptdump.c:282:15 > shift exponent 34 is too large for 32-bit type 'int' > CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200303+ #13 > Call Trace: > dump_stack+0xf4/0x164 (unreliable) > ubsan_epilogue+0x18/0x78 > __ubsan_handle_shift_out_of_bounds+0x160/0x21c > walk_pagetables+0x2cc/0x700 > walk_pud at arch/powerpc/mm/ptdump/ptdump.c:282 > (inlined by) walk_pagetables at arch/powerpc/mm/ptdump/ptdump.c:311 > ptdump_check_wx+0x8c/0xf0 > mark_rodata_ro+0x48/0x80 > kernel_init+0x74/0x194 > ret_from_kernel_thread+0x5c/0x74 > > Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> > Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> > --- > > v3: convert pud_index() etc to static inline functions. > v2: convert pud_offset() etc to static inline functions. > > arch/powerpc/include/asm/book3s/64/pgtable.h | 23 ++++++++++++++++---- > 1 file changed, 19 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h > index 201a69e6a355..bd432c6706b9 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -998,10 +998,25 @@ extern struct page *pgd_page(pgd_t pgd); > #define pud_page_vaddr(pud) __va(pud_val(pud) & ~PUD_MASKED_BITS) > #define pgd_page_vaddr(pgd) __va(pgd_val(pgd) & ~PGD_MASKED_BITS) > > -#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & (PTRS_PER_PGD - 1)) > -#define pud_index(address) (((address) >> (PUD_SHIFT)) & (PTRS_PER_PUD - 1)) > -#define pmd_index(address) (((address) >> (PMD_SHIFT)) & (PTRS_PER_PMD - 1)) > -#define pte_index(address) (((address) >> (PAGE_SHIFT)) & (PTRS_PER_PTE - 1)) > +static inline unsigned long pgd_index(unsigned long address) > +{ > + return (address >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1); > +} > + > +static inline unsigned long pud_index(unsigned long address) > +{ > + return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1); > +} > + > +static inline unsigned long pmd_index(unsigned long address) > +{ > + return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); > +} > + > +static inline unsigned long pte_index(unsigned long address) > +{ > + return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1); > +} > > /* > * Find an entry in a page-table-directory. We combine the address region >
> On Mar 6, 2020, at 1:56 AM, Christophe Leroy <christophe.leroy@c-s.fr> wrote: > > > > Le 06/03/2020 à 05:48, Qian Cai a écrit : >> Booting a power9 server with hash MMU could trigger an undefined >> behaviour because pud_offset(p4d, 0) will do, >> 0 >> (PAGE_SHIFT:16 + PTE_INDEX_SIZE:8 + H_PMD_INDEX_SIZE:10) >> Fix it by converting pud_index() and friends to static inline >> functions. >> UBSAN: shift-out-of-bounds in arch/powerpc/mm/ptdump/ptdump.c:282:15 >> shift exponent 34 is too large for 32-bit type 'int' >> CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200303+ #13 >> Call Trace: >> dump_stack+0xf4/0x164 (unreliable) >> ubsan_epilogue+0x18/0x78 >> __ubsan_handle_shift_out_of_bounds+0x160/0x21c >> walk_pagetables+0x2cc/0x700 >> walk_pud at arch/powerpc/mm/ptdump/ptdump.c:282 >> (inlined by) walk_pagetables at arch/powerpc/mm/ptdump/ptdump.c:311 >> ptdump_check_wx+0x8c/0xf0 >> mark_rodata_ro+0x48/0x80 >> kernel_init+0x74/0x194 >> ret_from_kernel_thread+0x5c/0x74 >> Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> >> Signed-off-by: Qian Cai <cai@lca.pw> > > Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Michael, can you take a look at this patch when you have a chance? It looks falling through the cracks. > >> --- >> v3: convert pud_index() etc to static inline functions. >> v2: convert pud_offset() etc to static inline functions. >> arch/powerpc/include/asm/book3s/64/pgtable.h | 23 ++++++++++++++++---- >> 1 file changed, 19 insertions(+), 4 deletions(-) >> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h >> index 201a69e6a355..bd432c6706b9 100644 >> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h >> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h >> @@ -998,10 +998,25 @@ extern struct page *pgd_page(pgd_t pgd); >> #define pud_page_vaddr(pud) __va(pud_val(pud) & ~PUD_MASKED_BITS) >> #define pgd_page_vaddr(pgd) __va(pgd_val(pgd) & ~PGD_MASKED_BITS) >> -#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & (PTRS_PER_PGD - 1)) >> -#define pud_index(address) (((address) >> (PUD_SHIFT)) & (PTRS_PER_PUD - 1)) >> -#define pmd_index(address) (((address) >> (PMD_SHIFT)) & (PTRS_PER_PMD - 1)) >> -#define pte_index(address) (((address) >> (PAGE_SHIFT)) & (PTRS_PER_PTE - 1)) >> +static inline unsigned long pgd_index(unsigned long address) >> +{ >> + return (address >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1); >> +} >> + >> +static inline unsigned long pud_index(unsigned long address) >> +{ >> + return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1); >> +} >> + >> +static inline unsigned long pmd_index(unsigned long address) >> +{ >> + return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); >> +} >> + >> +static inline unsigned long pte_index(unsigned long address) >> +{ >> + return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1); >> +} >> /* >> * Find an entry in a page-table-directory. We combine the address region
On Thu, 5 Mar 2020 23:48:52 -0500, Qian Cai wrote: > Booting a power9 server with hash MMU could trigger an undefined > behaviour because pud_offset(p4d, 0) will do, > > 0 >> (PAGE_SHIFT:16 + PTE_INDEX_SIZE:8 + H_PMD_INDEX_SIZE:10) > > Fix it by converting pud_index() and friends to static inline > functions. > > [...] Applied to powerpc/next. [1/1] powerpc/64s/pgtable: fix an undefined behaviour https://git.kernel.org/powerpc/c/c2e929b18cea6cbf71364f22d742d9aad7f4677a cheers
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 201a69e6a355..bd432c6706b9 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -998,10 +998,25 @@ extern struct page *pgd_page(pgd_t pgd); #define pud_page_vaddr(pud) __va(pud_val(pud) & ~PUD_MASKED_BITS) #define pgd_page_vaddr(pgd) __va(pgd_val(pgd) & ~PGD_MASKED_BITS) -#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & (PTRS_PER_PGD - 1)) -#define pud_index(address) (((address) >> (PUD_SHIFT)) & (PTRS_PER_PUD - 1)) -#define pmd_index(address) (((address) >> (PMD_SHIFT)) & (PTRS_PER_PMD - 1)) -#define pte_index(address) (((address) >> (PAGE_SHIFT)) & (PTRS_PER_PTE - 1)) +static inline unsigned long pgd_index(unsigned long address) +{ + return (address >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1); +} + +static inline unsigned long pud_index(unsigned long address) +{ + return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1); +} + +static inline unsigned long pmd_index(unsigned long address) +{ + return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); +} + +static inline unsigned long pte_index(unsigned long address) +{ + return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1); +} /* * Find an entry in a page-table-directory. We combine the address region
Booting a power9 server with hash MMU could trigger an undefined behaviour because pud_offset(p4d, 0) will do, 0 >> (PAGE_SHIFT:16 + PTE_INDEX_SIZE:8 + H_PMD_INDEX_SIZE:10) Fix it by converting pud_index() and friends to static inline functions. UBSAN: shift-out-of-bounds in arch/powerpc/mm/ptdump/ptdump.c:282:15 shift exponent 34 is too large for 32-bit type 'int' CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4-next-20200303+ #13 Call Trace: dump_stack+0xf4/0x164 (unreliable) ubsan_epilogue+0x18/0x78 __ubsan_handle_shift_out_of_bounds+0x160/0x21c walk_pagetables+0x2cc/0x700 walk_pud at arch/powerpc/mm/ptdump/ptdump.c:282 (inlined by) walk_pagetables at arch/powerpc/mm/ptdump/ptdump.c:311 ptdump_check_wx+0x8c/0xf0 mark_rodata_ro+0x48/0x80 kernel_init+0x74/0x194 ret_from_kernel_thread+0x5c/0x74 Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Qian Cai <cai@lca.pw> --- v3: convert pud_index() etc to static inline functions. v2: convert pud_offset() etc to static inline functions. arch/powerpc/include/asm/book3s/64/pgtable.h | 23 ++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-)