| Message ID | afd95fa4747f1c1eb66677025c2c7c9055f43cce.1547652372.git.christophe.leroy@c-s.fr (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3,1/2] mm: add probe_user_read() | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | next/apply_patch Successfully applied |
| snowpatch_ozlabs/build-ppc64le | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-ppc64be | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-ppc64e | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/build-pmac32 | success | build succeeded & removed 0 sparse warning(s) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 119 lines checked |
Christophe Leroy <christophe.leroy@c-s.fr> writes: > Instead of opencoding, use probe_user_read() to failessly > read a user location. > > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> > --- > v3: No change > > v2: Using probe_user_read() instead of probe_user_address() > > arch/powerpc/kernel/process.c | 12 +----------- > arch/powerpc/mm/fault.c | 6 +----- > arch/powerpc/perf/callchain.c | 20 +++----------------- > arch/powerpc/perf/core-book3s.c | 8 +------- > arch/powerpc/sysdev/fsl_pci.c | 10 ++++------ > 5 files changed, 10 insertions(+), 46 deletions(-) Looks good. Acked-by: Michael Ellerman <mpe@ellerman.id.au> cheers > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c > index ce393df243aa..6a4b59d574c2 100644 > --- a/arch/powerpc/kernel/process.c > +++ b/arch/powerpc/kernel/process.c > @@ -1298,16 +1298,6 @@ void show_user_instructions(struct pt_regs *regs) > > pc = regs->nip - (NR_INSN_TO_PRINT * 3 / 4 * sizeof(int)); > > - /* > - * Make sure the NIP points at userspace, not kernel text/data or > - * elsewhere. > - */ > - if (!__access_ok(pc, NR_INSN_TO_PRINT * sizeof(int), USER_DS)) { > - pr_info("%s[%d]: Bad NIP, not dumping instructions.\n", > - current->comm, current->pid); > - return; > - } > - > seq_buf_init(&s, buf, sizeof(buf)); > > while (n) { > @@ -1318,7 +1308,7 @@ void show_user_instructions(struct pt_regs *regs) > for (i = 0; i < 8 && n; i++, n--, pc += sizeof(int)) { > int instr; > > - if (probe_kernel_address((const void *)pc, instr)) { > + if (probe_user_read(&instr, (void __user *)pc, sizeof(instr))) { > seq_buf_printf(&s, "XXXXXXXX "); > continue; > } > diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c > index 887f11bcf330..ec74305fa330 100644 > --- a/arch/powerpc/mm/fault.c > +++ b/arch/powerpc/mm/fault.c > @@ -276,12 +276,8 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, > if ((flags & FAULT_FLAG_WRITE) && (flags & FAULT_FLAG_USER) && > access_ok(nip, sizeof(*nip))) { > unsigned int inst; > - int res; > > - pagefault_disable(); > - res = __get_user_inatomic(inst, nip); > - pagefault_enable(); > - if (!res) > + if (!probe_user_read(&inst, nip, sizeof(inst))) > return !store_updates_sp(inst); > *must_retry = true; > } > diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c > index 0af051a1974e..0680efb2237b 100644 > --- a/arch/powerpc/perf/callchain.c > +++ b/arch/powerpc/perf/callchain.c > @@ -159,12 +159,8 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret) > ((unsigned long)ptr & 7)) > return -EFAULT; > > - pagefault_disable(); > - if (!__get_user_inatomic(*ret, ptr)) { > - pagefault_enable(); > + if (!probe_user_read(ret, ptr, sizeof(*ret))) > return 0; > - } > - pagefault_enable(); > > return read_user_stack_slow(ptr, ret, 8); > } > @@ -175,12 +171,8 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) > ((unsigned long)ptr & 3)) > return -EFAULT; > > - pagefault_disable(); > - if (!__get_user_inatomic(*ret, ptr)) { > - pagefault_enable(); > + if (!probe_user_read(ret, ptr, sizeof(*ret))) > return 0; > - } > - pagefault_enable(); > > return read_user_stack_slow(ptr, ret, 4); > } > @@ -307,17 +299,11 @@ static inline int current_is_64bit(void) > */ > static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) > { > - int rc; > - > if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) || > ((unsigned long)ptr & 3)) > return -EFAULT; > > - pagefault_disable(); > - rc = __get_user_inatomic(*ret, ptr); > - pagefault_enable(); > - > - return rc; > + return probe_user_read(ret, ptr, sizeof(*ret)); > } > > static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry, > diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c > index b0723002a396..4b64ddf0db68 100644 > --- a/arch/powerpc/perf/core-book3s.c > +++ b/arch/powerpc/perf/core-book3s.c > @@ -416,7 +416,6 @@ static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) > static __u64 power_pmu_bhrb_to(u64 addr) > { > unsigned int instr; > - int ret; > __u64 target; > > if (is_kernel_addr(addr)) { > @@ -427,13 +426,8 @@ static __u64 power_pmu_bhrb_to(u64 addr) > } > > /* Userspace: need copy instruction here then translate it */ > - pagefault_disable(); > - ret = __get_user_inatomic(instr, (unsigned int __user *)addr); > - if (ret) { > - pagefault_enable(); > + if (probe_user_read(&instr, (unsigned int __user *)addr, sizeof(instr))) > return 0; > - } > - pagefault_enable(); > > target = branch_target(&instr); > if ((!target) || (instr & BRANCH_ABSOLUTE)) > diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c > index 918be816b097..c8a1b26489f5 100644 > --- a/arch/powerpc/sysdev/fsl_pci.c > +++ b/arch/powerpc/sysdev/fsl_pci.c > @@ -1068,13 +1068,11 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs) > addr += mfspr(SPRN_MCAR); > > if (is_in_pci_mem_space(addr)) { > - if (user_mode(regs)) { > - pagefault_disable(); > - ret = get_user(inst, (__u32 __user *)regs->nip); > - pagefault_enable(); > - } else { > + if (user_mode(regs)) > + ret = probe_user_read(&inst, (void __user *)regs->nip, > + sizeof(inst)); > + else > ret = probe_kernel_address((void *)regs->nip, inst); > - } > > if (!ret && mcheck_handle_load(regs, inst)) { > regs->nip += 4; > -- > 2.13.3
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index ce393df243aa..6a4b59d574c2 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1298,16 +1298,6 @@ void show_user_instructions(struct pt_regs *regs) pc = regs->nip - (NR_INSN_TO_PRINT * 3 / 4 * sizeof(int)); - /* - * Make sure the NIP points at userspace, not kernel text/data or - * elsewhere. - */ - if (!__access_ok(pc, NR_INSN_TO_PRINT * sizeof(int), USER_DS)) { - pr_info("%s[%d]: Bad NIP, not dumping instructions.\n", - current->comm, current->pid); - return; - } - seq_buf_init(&s, buf, sizeof(buf)); while (n) { @@ -1318,7 +1308,7 @@ void show_user_instructions(struct pt_regs *regs) for (i = 0; i < 8 && n; i++, n--, pc += sizeof(int)) { int instr; - if (probe_kernel_address((const void *)pc, instr)) { + if (probe_user_read(&instr, (void __user *)pc, sizeof(instr))) { seq_buf_printf(&s, "XXXXXXXX "); continue; } diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 887f11bcf330..ec74305fa330 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -276,12 +276,8 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, if ((flags & FAULT_FLAG_WRITE) && (flags & FAULT_FLAG_USER) && access_ok(nip, sizeof(*nip))) { unsigned int inst; - int res; - pagefault_disable(); - res = __get_user_inatomic(inst, nip); - pagefault_enable(); - if (!res) + if (!probe_user_read(&inst, nip, sizeof(inst))) return !store_updates_sp(inst); *must_retry = true; } diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c index 0af051a1974e..0680efb2237b 100644 --- a/arch/powerpc/perf/callchain.c +++ b/arch/powerpc/perf/callchain.c @@ -159,12 +159,8 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret) ((unsigned long)ptr & 7)) return -EFAULT; - pagefault_disable(); - if (!__get_user_inatomic(*ret, ptr)) { - pagefault_enable(); + if (!probe_user_read(ret, ptr, sizeof(*ret))) return 0; - } - pagefault_enable(); return read_user_stack_slow(ptr, ret, 8); } @@ -175,12 +171,8 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) ((unsigned long)ptr & 3)) return -EFAULT; - pagefault_disable(); - if (!__get_user_inatomic(*ret, ptr)) { - pagefault_enable(); + if (!probe_user_read(ret, ptr, sizeof(*ret))) return 0; - } - pagefault_enable(); return read_user_stack_slow(ptr, ret, 4); } @@ -307,17 +299,11 @@ static inline int current_is_64bit(void) */ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) { - int rc; - if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) || ((unsigned long)ptr & 3)) return -EFAULT; - pagefault_disable(); - rc = __get_user_inatomic(*ret, ptr); - pagefault_enable(); - - return rc; + return probe_user_read(ret, ptr, sizeof(*ret)); } static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry, diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index b0723002a396..4b64ddf0db68 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -416,7 +416,6 @@ static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) static __u64 power_pmu_bhrb_to(u64 addr) { unsigned int instr; - int ret; __u64 target; if (is_kernel_addr(addr)) { @@ -427,13 +426,8 @@ static __u64 power_pmu_bhrb_to(u64 addr) } /* Userspace: need copy instruction here then translate it */ - pagefault_disable(); - ret = __get_user_inatomic(instr, (unsigned int __user *)addr); - if (ret) { - pagefault_enable(); + if (probe_user_read(&instr, (unsigned int __user *)addr, sizeof(instr))) return 0; - } - pagefault_enable(); target = branch_target(&instr); if ((!target) || (instr & BRANCH_ABSOLUTE)) diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c index 918be816b097..c8a1b26489f5 100644 --- a/arch/powerpc/sysdev/fsl_pci.c +++ b/arch/powerpc/sysdev/fsl_pci.c @@ -1068,13 +1068,11 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs) addr += mfspr(SPRN_MCAR); if (is_in_pci_mem_space(addr)) { - if (user_mode(regs)) { - pagefault_disable(); - ret = get_user(inst, (__u32 __user *)regs->nip); - pagefault_enable(); - } else { + if (user_mode(regs)) + ret = probe_user_read(&inst, (void __user *)regs->nip, + sizeof(inst)); + else ret = probe_kernel_address((void *)regs->nip, inst); - } if (!ret && mcheck_handle_load(regs, inst)) { regs->nip += 4;
Instead of opencoding, use probe_user_read() to failessly read a user location. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> --- v3: No change v2: Using probe_user_read() instead of probe_user_address() arch/powerpc/kernel/process.c | 12 +----------- arch/powerpc/mm/fault.c | 6 +----- arch/powerpc/perf/callchain.c | 20 +++----------------- arch/powerpc/perf/core-book3s.c | 8 +------- arch/powerpc/sysdev/fsl_pci.c | 10 ++++------ 5 files changed, 10 insertions(+), 46 deletions(-)