| Message ID | 20200918132439.1475479-5-arnd@arndb.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | syscalls: remove compat_alloc_user_space callers | expand |
On Fri, Sep 18, 2020 at 03:24:39PM +0200, Arnd Bergmann wrote: > The compat implementations for mbind, get_mempolicy, set_mempolicy > and migrate_pages are just there to handle the subtly different > layout of bitmaps on 32-bit hosts. > > The compat implementation however lacks some of the checks that > are present in the native one, in particular for checking that > the extra bits are all zero when user space has a larger mask > size than the kernel. Worse, those extra bits do not get cleared > when copying in or out of the kernel, which can lead to incorrect > data as well. > > Unify the implementation to handle the compat bitmap layout directly > in the get_nodes() and copy_nodes_to_user() helpers. Splitting out > the get_bitmap() helper from get_nodes() also helps readability of the > native case. > > On x86, two additional problems are addressed by this: compat tasks can > pass a bitmap at the end of a mapping, causing a fault when reading > across the page boundary for a 64-bit word. x32 tasks might also run > into problems with get_mempolicy corrupting data when an odd number of > 32-bit words gets passed. > > On parisc the migrate_pages() system call apparently had the wrong > calling convention, as big-endian architectures expect the words > inside of a bitmap to be swapped. This is not a problem though > since parisc has no NUMA support. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > arch/arm64/include/asm/unistd32.h | 8 +- > arch/mips/kernel/syscalls/syscall_n32.tbl | 8 +- > arch/mips/kernel/syscalls/syscall_o32.tbl | 8 +- > arch/parisc/kernel/syscalls/syscall.tbl | 6 +- > arch/powerpc/kernel/syscalls/syscall.tbl | 8 +- > arch/s390/kernel/syscalls/syscall.tbl | 8 +- > arch/sparc/kernel/syscalls/syscall.tbl | 8 +- > arch/x86/entry/syscalls/syscall_32.tbl | 2 +- > include/linux/compat.h | 15 -- > include/uapi/asm-generic/unistd.h | 8 +- > kernel/kexec.c | 6 +- > kernel/sys_ni.c | 4 - > mm/mempolicy.c | 193 +++++----------------- > 13 files changed, 79 insertions(+), 203 deletions(-) > > diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h > index af793775ba98..31479f7120a0 100644 > --- a/arch/arm64/include/asm/unistd32.h > +++ b/arch/arm64/include/asm/unistd32.h > @@ -649,11 +649,11 @@ __SYSCALL(__NR_inotify_add_watch, sys_inotify_add_watch) > #define __NR_inotify_rm_watch 318 > __SYSCALL(__NR_inotify_rm_watch, sys_inotify_rm_watch) > #define __NR_mbind 319 > -__SYSCALL(__NR_mbind, compat_sys_mbind) > +__SYSCALL(__NR_mbind, sys_mbind) > #define __NR_get_mempolicy 320 > -__SYSCALL(__NR_get_mempolicy, compat_sys_get_mempolicy) > +__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy) > #define __NR_set_mempolicy 321 > -__SYSCALL(__NR_set_mempolicy, compat_sys_set_mempolicy) > +__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy) > #define __NR_openat 322 > __SYSCALL(__NR_openat, compat_sys_openat) > #define __NR_mkdirat 323 > @@ -811,7 +811,7 @@ __SYSCALL(__NR_rseq, sys_rseq) > #define __NR_io_pgetevents 399 > __SYSCALL(__NR_io_pgetevents, compat_sys_io_pgetevents) > #define __NR_migrate_pages 400 > -__SYSCALL(__NR_migrate_pages, compat_sys_migrate_pages) > +__SYSCALL(__NR_migrate_pages, sys_migrate_pages) > #define __NR_kexec_file_load 401 > __SYSCALL(__NR_kexec_file_load, sys_kexec_file_load) > /* 402 is unused */ > diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl > index 7fa1ca45e44c..15fda882d07e 100644 > --- a/arch/mips/kernel/syscalls/syscall_n32.tbl > +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl > @@ -239,9 +239,9 @@ > 228 n32 clock_nanosleep sys_clock_nanosleep_time32 > 229 n32 tgkill sys_tgkill > 230 n32 utimes sys_utimes_time32 > -231 n32 mbind compat_sys_mbind > -232 n32 get_mempolicy compat_sys_get_mempolicy > -233 n32 set_mempolicy compat_sys_set_mempolicy > +231 n32 mbind sys_mbind > +232 n32 get_mempolicy sys_get_mempolicy > +233 n32 set_mempolicy sys_set_mempolicy > 234 n32 mq_open compat_sys_mq_open > 235 n32 mq_unlink sys_mq_unlink > 236 n32 mq_timedsend sys_mq_timedsend_time32 > @@ -258,7 +258,7 @@ > 247 n32 inotify_init sys_inotify_init > 248 n32 inotify_add_watch sys_inotify_add_watch > 249 n32 inotify_rm_watch sys_inotify_rm_watch > -250 n32 migrate_pages compat_sys_migrate_pages > +250 n32 migrate_pages sys_migrate_pages > 251 n32 openat sys_openat > 252 n32 mkdirat sys_mkdirat > 253 n32 mknodat sys_mknodat > diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl > index 194c7fbeedf7..6591388a9d88 100644 > --- a/arch/mips/kernel/syscalls/syscall_o32.tbl > +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl > @@ -279,9 +279,9 @@ > 265 o32 clock_nanosleep sys_clock_nanosleep_time32 > 266 o32 tgkill sys_tgkill > 267 o32 utimes sys_utimes_time32 > -268 o32 mbind sys_mbind compat_sys_mbind > -269 o32 get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > -270 o32 set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy > +268 o32 mbind sys_mbind > +269 o32 get_mempolicy sys_get_mempolicy > +270 o32 set_mempolicy sys_set_mempolicy > 271 o32 mq_open sys_mq_open compat_sys_mq_open > 272 o32 mq_unlink sys_mq_unlink > 273 o32 mq_timedsend sys_mq_timedsend_time32 > @@ -298,7 +298,7 @@ > 284 o32 inotify_init sys_inotify_init > 285 o32 inotify_add_watch sys_inotify_add_watch > 286 o32 inotify_rm_watch sys_inotify_rm_watch > -287 o32 migrate_pages sys_migrate_pages compat_sys_migrate_pages > +287 o32 migrate_pages sys_migrate_pages > 288 o32 openat sys_openat compat_sys_openat > 289 o32 mkdirat sys_mkdirat > 290 o32 mknodat sys_mknodat > diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl > index 5c17edaffe70..30f3c0146abf 100644 > --- a/arch/parisc/kernel/syscalls/syscall.tbl > +++ b/arch/parisc/kernel/syscalls/syscall.tbl > @@ -292,9 +292,9 @@ > 258 32 clock_nanosleep sys_clock_nanosleep_time32 > 258 64 clock_nanosleep sys_clock_nanosleep > 259 common tgkill sys_tgkill > -260 common mbind sys_mbind compat_sys_mbind > -261 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > -262 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy > +260 common mbind sys_mbind > +261 common get_mempolicy sys_get_mempolicy > +262 common set_mempolicy sys_set_mempolicy > # 263 was vserver > 264 common add_key sys_add_key > 265 common request_key sys_request_key > diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl > index 04fb42d7b377..4f5216320721 100644 > --- a/arch/powerpc/kernel/syscalls/syscall.tbl > +++ b/arch/powerpc/kernel/syscalls/syscall.tbl > @@ -338,10 +338,10 @@ > 256 64 sys_debug_setcontext sys_ni_syscall > 256 spu sys_debug_setcontext sys_ni_syscall > # 257 reserved for vserver > -258 nospu migrate_pages sys_migrate_pages compat_sys_migrate_pages > -259 nospu mbind sys_mbind compat_sys_mbind > -260 nospu get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > -261 nospu set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy > +258 nospu migrate_pages sys_migrate_pages > +259 nospu mbind sys_mbind > +260 nospu get_mempolicy sys_get_mempolicy > +261 nospu set_mempolicy sys_set_mempolicy > 262 nospu mq_open sys_mq_open compat_sys_mq_open > 263 nospu mq_unlink sys_mq_unlink > 264 32 mq_timedsend sys_mq_timedsend_time32 > diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl > index 3197965d45e9..70c0b830d14f 100644 > --- a/arch/s390/kernel/syscalls/syscall.tbl > +++ b/arch/s390/kernel/syscalls/syscall.tbl > @@ -274,9 +274,9 @@ > 265 common statfs64 sys_statfs64 compat_sys_statfs64 > 266 common fstatfs64 sys_fstatfs64 compat_sys_fstatfs64 > 267 common remap_file_pages sys_remap_file_pages sys_remap_file_pages > -268 common mbind sys_mbind compat_sys_mbind > -269 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > -270 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy > +268 common mbind sys_mbind sys_mbind > +269 common get_mempolicy sys_get_mempolicy sys_get_mempolicy > +270 common set_mempolicy sys_set_mempolicy sys_set_mempolicy > 271 common mq_open sys_mq_open compat_sys_mq_open > 272 common mq_unlink sys_mq_unlink sys_mq_unlink > 273 common mq_timedsend sys_mq_timedsend sys_mq_timedsend_time32 > @@ -293,7 +293,7 @@ > 284 common inotify_init sys_inotify_init sys_inotify_init > 285 common inotify_add_watch sys_inotify_add_watch sys_inotify_add_watch > 286 common inotify_rm_watch sys_inotify_rm_watch sys_inotify_rm_watch > -287 common migrate_pages sys_migrate_pages compat_sys_migrate_pages > +287 common migrate_pages sys_migrate_pages sys_migrate_pages > 288 common openat sys_openat compat_sys_openat > 289 common mkdirat sys_mkdirat sys_mkdirat > 290 common mknodat sys_mknodat sys_mknodat > diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl > index e36ac364e61a..50ff839a2661 100644 > --- a/arch/sparc/kernel/syscalls/syscall.tbl > +++ b/arch/sparc/kernel/syscalls/syscall.tbl > @@ -365,10 +365,10 @@ > 299 common unshare sys_unshare > 300 common set_robust_list sys_set_robust_list compat_sys_set_robust_list > 301 common get_robust_list sys_get_robust_list compat_sys_get_robust_list > -302 common migrate_pages sys_migrate_pages compat_sys_migrate_pages > -303 common mbind sys_mbind compat_sys_mbind > -304 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > -305 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy > +302 common migrate_pages sys_migrate_pages > +303 common mbind sys_mbind > +304 common get_mempolicy sys_get_mempolicy > +305 common set_mempolicy sys_set_mempolicy > 306 common kexec_load sys_kexec_load sys_kexec_load > 307 common move_pages sys_move_pages > 308 common getcpu sys_getcpu > diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl > index b3263b8b2eae..d07c3fbd4697 100644 > --- a/arch/x86/entry/syscalls/syscall_32.tbl > +++ b/arch/x86/entry/syscalls/syscall_32.tbl > @@ -286,7 +286,7 @@ > 272 i386 fadvise64_64 sys_ia32_fadvise64_64 > 273 i386 vserver > 274 i386 mbind sys_mbind > -275 i386 get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy > +275 i386 get_mempolicy sys_get_mempolicy > 276 i386 set_mempolicy sys_set_mempolicy > 277 i386 mq_open sys_mq_open compat_sys_mq_open > 278 i386 mq_unlink sys_mq_unlink > diff --git a/include/linux/compat.h b/include/linux/compat.h > index db1d7ac2c9e0..be06367b336c 100644 > --- a/include/linux/compat.h > +++ b/include/linux/compat.h > @@ -749,21 +749,6 @@ asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr > /* mm/fadvise.c: No generic prototype for fadvise64_64 */ > > /* mm/, CONFIG_MMU only */ > -asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len, > - compat_ulong_t mode, > - compat_ulong_t __user *nmask, > - compat_ulong_t maxnode, compat_ulong_t flags); > -asmlinkage long compat_sys_get_mempolicy(int __user *policy, > - compat_ulong_t __user *nmask, > - compat_ulong_t maxnode, > - compat_ulong_t addr, > - compat_ulong_t flags); > -asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask, > - compat_ulong_t maxnode); > -asmlinkage long compat_sys_migrate_pages(compat_pid_t pid, > - compat_ulong_t maxnode, const compat_ulong_t __user *old_nodes, > - const compat_ulong_t __user *new_nodes); > - > asmlinkage long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, > compat_pid_t pid, int sig, > struct compat_siginfo __user *uinfo); > diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h > index 4da51702fb21..4e31f9b68a8f 100644 > --- a/include/uapi/asm-generic/unistd.h > +++ b/include/uapi/asm-generic/unistd.h > @@ -673,13 +673,13 @@ __SYSCALL(__NR_madvise, sys_madvise) > #define __NR_remap_file_pages 234 > __SYSCALL(__NR_remap_file_pages, sys_remap_file_pages) > #define __NR_mbind 235 > -__SC_COMP(__NR_mbind, sys_mbind, compat_sys_mbind) > +__SYSCALL(__NR_mbind, sys_mbind) > #define __NR_get_mempolicy 236 > -__SC_COMP(__NR_get_mempolicy, sys_get_mempolicy, compat_sys_get_mempolicy) > +__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy) > #define __NR_set_mempolicy 237 > -__SC_COMP(__NR_set_mempolicy, sys_set_mempolicy, compat_sys_set_mempolicy) > +__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy) > #define __NR_migrate_pages 238 > -__SC_COMP(__NR_migrate_pages, sys_migrate_pages, compat_sys_migrate_pages) > +__SYSCALL(__NR_migrate_pages, sys_migrate_pages) > #define __NR_move_pages 239 > __SYSCALL(__NR_move_pages, sys_move_pages) > #endif > diff --git a/kernel/kexec.c b/kernel/kexec.c > index 1ef7d3dc906f..0fecf2370be1 100644 > --- a/kernel/kexec.c > +++ b/kernel/kexec.c > @@ -30,11 +30,13 @@ static int copy_user_segment_list(struct kimage *image, > image->nr_segments = nr_segments; > segment_bytes = nr_segments * sizeof(*segments); > if (in_compat_syscall()) { > - struct compat_kexec_segment __user *cs = (void __user *)segments; > + struct compat_kexec_segment __user *cs; > struct compat_kexec_segment segment; > int i; > + > + cs = (struct compat_kexec_segment __user *)segments; > for (i=0; i< nr_segments; i++) { > - copy_from_user(&segment, &cs[i], sizeof(segment)); > + ret = copy_from_user(&segment, &cs[i], sizeof(segment)); > if (ret) > break; > > diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c > index 783a24ceee88..0850111f888e 100644 > --- a/kernel/sys_ni.c > +++ b/kernel/sys_ni.c > @@ -282,13 +282,9 @@ COND_SYSCALL(mincore); > COND_SYSCALL(madvise); > COND_SYSCALL(remap_file_pages); > COND_SYSCALL(mbind); > -COND_SYSCALL_COMPAT(mbind); > COND_SYSCALL(get_mempolicy); > -COND_SYSCALL_COMPAT(get_mempolicy); > COND_SYSCALL(set_mempolicy); > -COND_SYSCALL_COMPAT(set_mempolicy); > COND_SYSCALL(migrate_pages); > -COND_SYSCALL_COMPAT(migrate_pages); > COND_SYSCALL(move_pages); > > COND_SYSCALL(perf_event_open); > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index eddbe4e56c73..2e1b90143b2c 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -1374,16 +1374,30 @@ static long do_mbind(unsigned long start, unsigned long len, > /* > * User space interface with variable sized bitmaps for nodelists. > */ > +static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask, > + unsigned long maxnode) > +{ > + unsigned long nlongs = BITS_TO_LONGS(maxnode); > + int ret; > + > + if (in_compat_syscall()) > + ret = compat_get_bitmap(mask, (void __user *)nmask, maxnode); I'd either pass void __user all the way, or do an explicit case from the native to the compat version in the compat handler. > + else > + ret = copy_from_user(mask, nmask, nlongs*sizeof(unsigned long)); That whole BITS_TO_LONGS(b) * sizeof(unsigned long) pattern is duplicated in various places including the checking of compat vs native and probably want a helper that includes the in_compat_syscall() check.
On Sat, Sep 19, 2020 at 7:41 AM Christoph Hellwig <hch@infradead.org> wrote: > On Fri, Sep 18, 2020 at 03:24:39PM +0200, Arnd Bergmann wrote: > > +static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask, > > + unsigned long maxnode) > > +{ > > + unsigned long nlongs = BITS_TO_LONGS(maxnode); > > + int ret; > > + > > + if (in_compat_syscall()) > > + ret = compat_get_bitmap(mask, (void __user *)nmask, maxnode); > > I'd either pass void __user all the way, or do an explicit case from > the native to the compat version in the compat handler. Changed to if (in_compat_syscall()) ret = compat_get_bitmap(mask, (const compat_ulong_t __user *)nmask, maxnode); > > + else > > + ret = copy_from_user(mask, nmask, nlongs*sizeof(unsigned long)); > > That whole BITS_TO_LONGS(b) * sizeof(unsigned long) pattern is > duplicated in various places including the checking of compat vs native > and probably want a helper that includes the in_compat_syscall() check. I don't see what you mean here. I can see how having the helper would simplify copy_nodes_to_user(), but not how it can be shared with the use in get_bitmap()/get_nodes(). Arnd
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index af793775ba98..31479f7120a0 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -649,11 +649,11 @@ __SYSCALL(__NR_inotify_add_watch, sys_inotify_add_watch) #define __NR_inotify_rm_watch 318 __SYSCALL(__NR_inotify_rm_watch, sys_inotify_rm_watch) #define __NR_mbind 319 -__SYSCALL(__NR_mbind, compat_sys_mbind) +__SYSCALL(__NR_mbind, sys_mbind) #define __NR_get_mempolicy 320 -__SYSCALL(__NR_get_mempolicy, compat_sys_get_mempolicy) +__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy) #define __NR_set_mempolicy 321 -__SYSCALL(__NR_set_mempolicy, compat_sys_set_mempolicy) +__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy) #define __NR_openat 322 __SYSCALL(__NR_openat, compat_sys_openat) #define __NR_mkdirat 323 @@ -811,7 +811,7 @@ __SYSCALL(__NR_rseq, sys_rseq) #define __NR_io_pgetevents 399 __SYSCALL(__NR_io_pgetevents, compat_sys_io_pgetevents) #define __NR_migrate_pages 400 -__SYSCALL(__NR_migrate_pages, compat_sys_migrate_pages) +__SYSCALL(__NR_migrate_pages, sys_migrate_pages) #define __NR_kexec_file_load 401 __SYSCALL(__NR_kexec_file_load, sys_kexec_file_load) /* 402 is unused */ diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 7fa1ca45e44c..15fda882d07e 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -239,9 +239,9 @@ 228 n32 clock_nanosleep sys_clock_nanosleep_time32 229 n32 tgkill sys_tgkill 230 n32 utimes sys_utimes_time32 -231 n32 mbind compat_sys_mbind -232 n32 get_mempolicy compat_sys_get_mempolicy -233 n32 set_mempolicy compat_sys_set_mempolicy +231 n32 mbind sys_mbind +232 n32 get_mempolicy sys_get_mempolicy +233 n32 set_mempolicy sys_set_mempolicy 234 n32 mq_open compat_sys_mq_open 235 n32 mq_unlink sys_mq_unlink 236 n32 mq_timedsend sys_mq_timedsend_time32 @@ -258,7 +258,7 @@ 247 n32 inotify_init sys_inotify_init 248 n32 inotify_add_watch sys_inotify_add_watch 249 n32 inotify_rm_watch sys_inotify_rm_watch -250 n32 migrate_pages compat_sys_migrate_pages +250 n32 migrate_pages sys_migrate_pages 251 n32 openat sys_openat 252 n32 mkdirat sys_mkdirat 253 n32 mknodat sys_mknodat diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index 194c7fbeedf7..6591388a9d88 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -279,9 +279,9 @@ 265 o32 clock_nanosleep sys_clock_nanosleep_time32 266 o32 tgkill sys_tgkill 267 o32 utimes sys_utimes_time32 -268 o32 mbind sys_mbind compat_sys_mbind -269 o32 get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy -270 o32 set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy +268 o32 mbind sys_mbind +269 o32 get_mempolicy sys_get_mempolicy +270 o32 set_mempolicy sys_set_mempolicy 271 o32 mq_open sys_mq_open compat_sys_mq_open 272 o32 mq_unlink sys_mq_unlink 273 o32 mq_timedsend sys_mq_timedsend_time32 @@ -298,7 +298,7 @@ 284 o32 inotify_init sys_inotify_init 285 o32 inotify_add_watch sys_inotify_add_watch 286 o32 inotify_rm_watch sys_inotify_rm_watch -287 o32 migrate_pages sys_migrate_pages compat_sys_migrate_pages +287 o32 migrate_pages sys_migrate_pages 288 o32 openat sys_openat compat_sys_openat 289 o32 mkdirat sys_mkdirat 290 o32 mknodat sys_mknodat diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index 5c17edaffe70..30f3c0146abf 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -292,9 +292,9 @@ 258 32 clock_nanosleep sys_clock_nanosleep_time32 258 64 clock_nanosleep sys_clock_nanosleep 259 common tgkill sys_tgkill -260 common mbind sys_mbind compat_sys_mbind -261 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy -262 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy +260 common mbind sys_mbind +261 common get_mempolicy sys_get_mempolicy +262 common set_mempolicy sys_set_mempolicy # 263 was vserver 264 common add_key sys_add_key 265 common request_key sys_request_key diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index 04fb42d7b377..4f5216320721 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -338,10 +338,10 @@ 256 64 sys_debug_setcontext sys_ni_syscall 256 spu sys_debug_setcontext sys_ni_syscall # 257 reserved for vserver -258 nospu migrate_pages sys_migrate_pages compat_sys_migrate_pages -259 nospu mbind sys_mbind compat_sys_mbind -260 nospu get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy -261 nospu set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy +258 nospu migrate_pages sys_migrate_pages +259 nospu mbind sys_mbind +260 nospu get_mempolicy sys_get_mempolicy +261 nospu set_mempolicy sys_set_mempolicy 262 nospu mq_open sys_mq_open compat_sys_mq_open 263 nospu mq_unlink sys_mq_unlink 264 32 mq_timedsend sys_mq_timedsend_time32 diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index 3197965d45e9..70c0b830d14f 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -274,9 +274,9 @@ 265 common statfs64 sys_statfs64 compat_sys_statfs64 266 common fstatfs64 sys_fstatfs64 compat_sys_fstatfs64 267 common remap_file_pages sys_remap_file_pages sys_remap_file_pages -268 common mbind sys_mbind compat_sys_mbind -269 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy -270 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy +268 common mbind sys_mbind sys_mbind +269 common get_mempolicy sys_get_mempolicy sys_get_mempolicy +270 common set_mempolicy sys_set_mempolicy sys_set_mempolicy 271 common mq_open sys_mq_open compat_sys_mq_open 272 common mq_unlink sys_mq_unlink sys_mq_unlink 273 common mq_timedsend sys_mq_timedsend sys_mq_timedsend_time32 @@ -293,7 +293,7 @@ 284 common inotify_init sys_inotify_init sys_inotify_init 285 common inotify_add_watch sys_inotify_add_watch sys_inotify_add_watch 286 common inotify_rm_watch sys_inotify_rm_watch sys_inotify_rm_watch -287 common migrate_pages sys_migrate_pages compat_sys_migrate_pages +287 common migrate_pages sys_migrate_pages sys_migrate_pages 288 common openat sys_openat compat_sys_openat 289 common mkdirat sys_mkdirat sys_mkdirat 290 common mknodat sys_mknodat sys_mknodat diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index e36ac364e61a..50ff839a2661 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -365,10 +365,10 @@ 299 common unshare sys_unshare 300 common set_robust_list sys_set_robust_list compat_sys_set_robust_list 301 common get_robust_list sys_get_robust_list compat_sys_get_robust_list -302 common migrate_pages sys_migrate_pages compat_sys_migrate_pages -303 common mbind sys_mbind compat_sys_mbind -304 common get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy -305 common set_mempolicy sys_set_mempolicy compat_sys_set_mempolicy +302 common migrate_pages sys_migrate_pages +303 common mbind sys_mbind +304 common get_mempolicy sys_get_mempolicy +305 common set_mempolicy sys_set_mempolicy 306 common kexec_load sys_kexec_load sys_kexec_load 307 common move_pages sys_move_pages 308 common getcpu sys_getcpu diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index b3263b8b2eae..d07c3fbd4697 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -286,7 +286,7 @@ 272 i386 fadvise64_64 sys_ia32_fadvise64_64 273 i386 vserver 274 i386 mbind sys_mbind -275 i386 get_mempolicy sys_get_mempolicy compat_sys_get_mempolicy +275 i386 get_mempolicy sys_get_mempolicy 276 i386 set_mempolicy sys_set_mempolicy 277 i386 mq_open sys_mq_open compat_sys_mq_open 278 i386 mq_unlink sys_mq_unlink diff --git a/include/linux/compat.h b/include/linux/compat.h index db1d7ac2c9e0..be06367b336c 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -749,21 +749,6 @@ asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr /* mm/fadvise.c: No generic prototype for fadvise64_64 */ /* mm/, CONFIG_MMU only */ -asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len, - compat_ulong_t mode, - compat_ulong_t __user *nmask, - compat_ulong_t maxnode, compat_ulong_t flags); -asmlinkage long compat_sys_get_mempolicy(int __user *policy, - compat_ulong_t __user *nmask, - compat_ulong_t maxnode, - compat_ulong_t addr, - compat_ulong_t flags); -asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask, - compat_ulong_t maxnode); -asmlinkage long compat_sys_migrate_pages(compat_pid_t pid, - compat_ulong_t maxnode, const compat_ulong_t __user *old_nodes, - const compat_ulong_t __user *new_nodes); - asmlinkage long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig, struct compat_siginfo __user *uinfo); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 4da51702fb21..4e31f9b68a8f 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -673,13 +673,13 @@ __SYSCALL(__NR_madvise, sys_madvise) #define __NR_remap_file_pages 234 __SYSCALL(__NR_remap_file_pages, sys_remap_file_pages) #define __NR_mbind 235 -__SC_COMP(__NR_mbind, sys_mbind, compat_sys_mbind) +__SYSCALL(__NR_mbind, sys_mbind) #define __NR_get_mempolicy 236 -__SC_COMP(__NR_get_mempolicy, sys_get_mempolicy, compat_sys_get_mempolicy) +__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy) #define __NR_set_mempolicy 237 -__SC_COMP(__NR_set_mempolicy, sys_set_mempolicy, compat_sys_set_mempolicy) +__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy) #define __NR_migrate_pages 238 -__SC_COMP(__NR_migrate_pages, sys_migrate_pages, compat_sys_migrate_pages) +__SYSCALL(__NR_migrate_pages, sys_migrate_pages) #define __NR_move_pages 239 __SYSCALL(__NR_move_pages, sys_move_pages) #endif diff --git a/kernel/kexec.c b/kernel/kexec.c index 1ef7d3dc906f..0fecf2370be1 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -30,11 +30,13 @@ static int copy_user_segment_list(struct kimage *image, image->nr_segments = nr_segments; segment_bytes = nr_segments * sizeof(*segments); if (in_compat_syscall()) { - struct compat_kexec_segment __user *cs = (void __user *)segments; + struct compat_kexec_segment __user *cs; struct compat_kexec_segment segment; int i; + + cs = (struct compat_kexec_segment __user *)segments; for (i=0; i< nr_segments; i++) { - copy_from_user(&segment, &cs[i], sizeof(segment)); + ret = copy_from_user(&segment, &cs[i], sizeof(segment)); if (ret) break; diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 783a24ceee88..0850111f888e 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -282,13 +282,9 @@ COND_SYSCALL(mincore); COND_SYSCALL(madvise); COND_SYSCALL(remap_file_pages); COND_SYSCALL(mbind); -COND_SYSCALL_COMPAT(mbind); COND_SYSCALL(get_mempolicy); -COND_SYSCALL_COMPAT(get_mempolicy); COND_SYSCALL(set_mempolicy); -COND_SYSCALL_COMPAT(set_mempolicy); COND_SYSCALL(migrate_pages); -COND_SYSCALL_COMPAT(migrate_pages); COND_SYSCALL(move_pages); COND_SYSCALL(perf_event_open); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index eddbe4e56c73..2e1b90143b2c 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1374,16 +1374,30 @@ static long do_mbind(unsigned long start, unsigned long len, /* * User space interface with variable sized bitmaps for nodelists. */ +static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask, + unsigned long maxnode) +{ + unsigned long nlongs = BITS_TO_LONGS(maxnode); + int ret; + + if (in_compat_syscall()) + ret = compat_get_bitmap(mask, (void __user *)nmask, maxnode); + else + ret = copy_from_user(mask, nmask, nlongs*sizeof(unsigned long)); + + if (ret) + return -EFAULT; + + if (maxnode % BITS_PER_LONG) + mask[nlongs-1] &= (1UL << (maxnode % BITS_PER_LONG)) - 1; + + return 0; +} /* Copy a node mask from user space. */ static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, unsigned long maxnode) { - unsigned long k; - unsigned long t; - unsigned long nlongs; - unsigned long endmask; - --maxnode; nodes_clear(*nodes); if (maxnode == 0 || !nmask) @@ -1391,49 +1405,29 @@ static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, if (maxnode > PAGE_SIZE*BITS_PER_BYTE) return -EINVAL; - nlongs = BITS_TO_LONGS(maxnode); - if ((maxnode % BITS_PER_LONG) == 0) - endmask = ~0UL; - else - endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1; - /* * When the user specified more nodes than supported just check - * if the non supported part is all zero. - * - * If maxnode have more longs than MAX_NUMNODES, check - * the bits in that area first. And then go through to - * check the rest bits which equal or bigger than MAX_NUMNODES. - * Otherwise, just check bits [MAX_NUMNODES, maxnode). + * if the non supported part is all zero, one word at a time, + * starting at the end. */ - if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) { - for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) { - if (get_user(t, nmask + k)) - return -EFAULT; - if (k == nlongs - 1) { - if (t & endmask) - return -EINVAL; - } else if (t) - return -EINVAL; - } - nlongs = BITS_TO_LONGS(MAX_NUMNODES); - endmask = ~0UL; - } - - if (maxnode > MAX_NUMNODES && MAX_NUMNODES % BITS_PER_LONG != 0) { - unsigned long valid_mask = endmask; + while (maxnode > MAX_NUMNODES) { + unsigned long bits = min_t(unsigned long, maxnode, BITS_PER_LONG); + unsigned long t; - valid_mask &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1); - if (get_user(t, nmask + nlongs - 1)) + if (get_bitmap(&t, &nmask[maxnode / BITS_PER_LONG], bits)) return -EFAULT; - if (t & valid_mask) + + if (maxnode - bits >= MAX_NUMNODES) { + maxnode -= bits; + } else { + maxnode = MAX_NUMNODES; + t &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1); + } + if (t) return -EINVAL; } - if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long))) - return -EFAULT; - nodes_addr(*nodes)[nlongs-1] &= endmask; - return 0; + return get_bitmap(nodes_addr(*nodes), nmask, maxnode); } /* Copy a kernel node mask to user space */ @@ -1442,6 +1436,10 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, { unsigned long copy = ALIGN(maxnode-1, 64) / 8; unsigned int nbytes = BITS_TO_LONGS(nr_node_ids) * sizeof(long); + bool compat = in_compat_syscall(); + + if (compat) + nbytes = BITS_TO_COMPAT_LONGS(nr_node_ids) * sizeof(compat_long_t); if (copy > nbytes) { if (copy > PAGE_SIZE) @@ -1450,6 +1448,11 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, return -EFAULT; copy = nbytes; } + + if (compat) + return compat_put_bitmap((compat_ulong_t __user *)mask, + nodes_addr(*nodes), maxnode); + return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; } @@ -1641,116 +1644,6 @@ SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags); } -#ifdef CONFIG_COMPAT - -COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, - compat_ulong_t __user *, nmask, - compat_ulong_t, maxnode, - compat_ulong_t, addr, compat_ulong_t, flags) -{ - long err; - unsigned long __user *nm = NULL; - unsigned long nr_bits, alloc_size; - DECLARE_BITMAP(bm, MAX_NUMNODES); - - nr_bits = min_t(unsigned long, maxnode-1, nr_node_ids); - alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; - - if (nmask) - nm = compat_alloc_user_space(alloc_size); - - err = kernel_get_mempolicy(policy, nm, nr_bits+1, addr, flags); - - if (!err && nmask) { - unsigned long copy_size; - copy_size = min_t(unsigned long, sizeof(bm), alloc_size); - err = copy_from_user(bm, nm, copy_size); - /* ensure entire bitmap is zeroed */ - err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8); - err |= compat_put_bitmap(nmask, bm, nr_bits); - } - - return err; -} - -COMPAT_SYSCALL_DEFINE3(set_mempolicy, int, mode, compat_ulong_t __user *, nmask, - compat_ulong_t, maxnode) -{ - unsigned long __user *nm = NULL; - unsigned long nr_bits, alloc_size; - DECLARE_BITMAP(bm, MAX_NUMNODES); - - nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); - alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; - - if (nmask) { - if (compat_get_bitmap(bm, nmask, nr_bits)) - return -EFAULT; - nm = compat_alloc_user_space(alloc_size); - if (copy_to_user(nm, bm, alloc_size)) - return -EFAULT; - } - - return kernel_set_mempolicy(mode, nm, nr_bits+1); -} - -COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len, - compat_ulong_t, mode, compat_ulong_t __user *, nmask, - compat_ulong_t, maxnode, compat_ulong_t, flags) -{ - unsigned long __user *nm = NULL; - unsigned long nr_bits, alloc_size; - nodemask_t bm; - - nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); - alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; - - if (nmask) { - if (compat_get_bitmap(nodes_addr(bm), nmask, nr_bits)) - return -EFAULT; - nm = compat_alloc_user_space(alloc_size); - if (copy_to_user(nm, nodes_addr(bm), alloc_size)) - return -EFAULT; - } - - return kernel_mbind(start, len, mode, nm, nr_bits+1, flags); -} - -COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid, - compat_ulong_t, maxnode, - const compat_ulong_t __user *, old_nodes, - const compat_ulong_t __user *, new_nodes) -{ - unsigned long __user *old = NULL; - unsigned long __user *new = NULL; - nodemask_t tmp_mask; - unsigned long nr_bits; - unsigned long size; - - nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES); - size = ALIGN(nr_bits, BITS_PER_LONG) / 8; - if (old_nodes) { - if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits)) - return -EFAULT; - old = compat_alloc_user_space(new_nodes ? size * 2 : size); - if (new_nodes) - new = old + size / sizeof(unsigned long); - if (copy_to_user(old, nodes_addr(tmp_mask), size)) - return -EFAULT; - } - if (new_nodes) { - if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits)) - return -EFAULT; - if (new == NULL) - new = compat_alloc_user_space(size); - if (copy_to_user(new, nodes_addr(tmp_mask), size)) - return -EFAULT; - } - return kernel_migrate_pages(pid, nr_bits + 1, old, new); -} - -#endif /* CONFIG_COMPAT */ - bool vma_migratable(struct vm_area_struct *vma) { if (vma->vm_flags & (VM_IO | VM_PFNMAP))
The compat implementations for mbind, get_mempolicy, set_mempolicy and migrate_pages are just there to handle the subtly different layout of bitmaps on 32-bit hosts. The compat implementation however lacks some of the checks that are present in the native one, in particular for checking that the extra bits are all zero when user space has a larger mask size than the kernel. Worse, those extra bits do not get cleared when copying in or out of the kernel, which can lead to incorrect data as well. Unify the implementation to handle the compat bitmap layout directly in the get_nodes() and copy_nodes_to_user() helpers. Splitting out the get_bitmap() helper from get_nodes() also helps readability of the native case. On x86, two additional problems are addressed by this: compat tasks can pass a bitmap at the end of a mapping, causing a fault when reading across the page boundary for a 64-bit word. x32 tasks might also run into problems with get_mempolicy corrupting data when an odd number of 32-bit words gets passed. On parisc the migrate_pages() system call apparently had the wrong calling convention, as big-endian architectures expect the words inside of a bitmap to be swapped. This is not a problem though since parisc has no NUMA support. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- arch/arm64/include/asm/unistd32.h | 8 +- arch/mips/kernel/syscalls/syscall_n32.tbl | 8 +- arch/mips/kernel/syscalls/syscall_o32.tbl | 8 +- arch/parisc/kernel/syscalls/syscall.tbl | 6 +- arch/powerpc/kernel/syscalls/syscall.tbl | 8 +- arch/s390/kernel/syscalls/syscall.tbl | 8 +- arch/sparc/kernel/syscalls/syscall.tbl | 8 +- arch/x86/entry/syscalls/syscall_32.tbl | 2 +- include/linux/compat.h | 15 -- include/uapi/asm-generic/unistd.h | 8 +- kernel/kexec.c | 6 +- kernel/sys_ni.c | 4 - mm/mempolicy.c | 193 +++++----------------- 13 files changed, 79 insertions(+), 203 deletions(-)