| Message ID | 2780c632bc2c6e39f27920f8cc98e17430189e27.1491991939.git.naveen.n.rao@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
On Wed, 12 Apr 2017 16:28:24 +0530 "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote: > The macro is now pretty long and ugly on powerpc. In the light of > further changes needed here, convert it to a __weak variant to be > over-ridden with a nicer looking function. Looks good to me. Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Thanks! > > Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> > Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> > --- > arch/powerpc/include/asm/kprobes.h | 53 ---------------------------------- > arch/powerpc/kernel/kprobes.c | 58 ++++++++++++++++++++++++++++++++++++++ > arch/powerpc/kernel/optprobes.c | 4 +-- > include/linux/kprobes.h | 1 + > kernel/kprobes.c | 20 ++++++------- > 5 files changed, 69 insertions(+), 67 deletions(-) > > diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h > index 0503c98b2117..a843884aafaf 100644 > --- a/arch/powerpc/include/asm/kprobes.h > +++ b/arch/powerpc/include/asm/kprobes.h > @@ -61,59 +61,6 @@ extern kprobe_opcode_t optprobe_template_end[]; > #define MAX_OPTINSN_SIZE (optprobe_template_end - optprobe_template_entry) > #define RELATIVEJUMP_SIZE sizeof(kprobe_opcode_t) /* 4 bytes */ > > -#ifdef PPC64_ELF_ABI_v2 > -/* PPC64 ABIv2 needs local entry point */ > -#define kprobe_lookup_name(name, addr) \ > -{ \ > - addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ > - if (addr) \ > - addr = (kprobe_opcode_t *)ppc_function_entry(addr); \ > -} > -#elif defined(PPC64_ELF_ABI_v1) > -/* > - * 64bit powerpc ABIv1 uses function descriptors: > - * - Check for the dot variant of the symbol first. > - * - If that fails, try looking up the symbol provided. > - * > - * This ensures we always get to the actual symbol and not the descriptor. > - * Also handle <module:symbol> format. > - */ > -#define kprobe_lookup_name(name, addr) \ > -{ \ > - char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; \ > - const char *modsym; \ > - bool dot_appended = false; \ > - if ((modsym = strchr(name, ':')) != NULL) { \ > - modsym++; \ > - if (*modsym != '\0' && *modsym != '.') { \ > - /* Convert to <module:.symbol> */ \ > - strncpy(dot_name, name, modsym - name); \ > - dot_name[modsym - name] = '.'; \ > - dot_name[modsym - name + 1] = '\0'; \ > - strncat(dot_name, modsym, \ > - sizeof(dot_name) - (modsym - name) - 2);\ > - dot_appended = true; \ > - } else { \ > - dot_name[0] = '\0'; \ > - strncat(dot_name, name, sizeof(dot_name) - 1); \ > - } \ > - } else if (name[0] != '.') { \ > - dot_name[0] = '.'; \ > - dot_name[1] = '\0'; \ > - strncat(dot_name, name, KSYM_NAME_LEN - 2); \ > - dot_appended = true; \ > - } else { \ > - dot_name[0] = '\0'; \ > - strncat(dot_name, name, KSYM_NAME_LEN - 1); \ > - } \ > - addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \ > - if (!addr && dot_appended) { \ > - /* Let's try the original non-dot symbol lookup */ \ > - addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ > - } \ > -} > -#endif > - > #define flush_insn_slot(p) do { } while (0) > #define kretprobe_blacklist_size 0 > > diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c > index 331751701fed..a7aa7394954d 100644 > --- a/arch/powerpc/kernel/kprobes.c > +++ b/arch/powerpc/kernel/kprobes.c > @@ -42,6 +42,64 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); > > struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}}; > > +kprobe_opcode_t *kprobe_lookup_name(const char *name) > +{ > + kprobe_opcode_t *addr; > + > +#ifdef PPC64_ELF_ABI_v2 > + /* PPC64 ABIv2 needs local entry point */ > + addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); > + if (addr) > + addr = (kprobe_opcode_t *)ppc_function_entry(addr); > +#elif defined(PPC64_ELF_ABI_v1) > + /* > + * 64bit powerpc ABIv1 uses function descriptors: > + * - Check for the dot variant of the symbol first. > + * - If that fails, try looking up the symbol provided. > + * > + * This ensures we always get to the actual symbol and not > + * the descriptor. > + * > + * Also handle <module:symbol> format. > + */ > + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; > + const char *modsym; > + bool dot_appended = false; > + if ((modsym = strchr(name, ':')) != NULL) { > + modsym++; > + if (*modsym != '\0' && *modsym != '.') { > + /* Convert to <module:.symbol> */ > + strncpy(dot_name, name, modsym - name); > + dot_name[modsym - name] = '.'; > + dot_name[modsym - name + 1] = '\0'; > + strncat(dot_name, modsym, > + sizeof(dot_name) - (modsym - name) - 2); > + dot_appended = true; > + } else { > + dot_name[0] = '\0'; > + strncat(dot_name, name, sizeof(dot_name) - 1); > + } > + } else if (name[0] != '.') { > + dot_name[0] = '.'; > + dot_name[1] = '\0'; > + strncat(dot_name, name, KSYM_NAME_LEN - 2); > + dot_appended = true; > + } else { > + dot_name[0] = '\0'; > + strncat(dot_name, name, KSYM_NAME_LEN - 1); > + } > + addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); > + if (!addr && dot_appended) { > + /* Let's try the original non-dot symbol lookup */ > + addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); > + } > +#else > + addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); > +#endif > + > + return addr; > +} > + > int __kprobes arch_prepare_kprobe(struct kprobe *p) > { > int ret = 0; > diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c > index 2282bf4e63cd..aefe076d00e0 100644 > --- a/arch/powerpc/kernel/optprobes.c > +++ b/arch/powerpc/kernel/optprobes.c > @@ -243,8 +243,8 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p) > /* > * 2. branch to optimized_callback() and emulate_step() > */ > - kprobe_lookup_name("optimized_callback", op_callback_addr); > - kprobe_lookup_name("emulate_step", emulate_step_addr); > + op_callback_addr = kprobe_lookup_name("optimized_callback"); > + emulate_step_addr = kprobe_lookup_name("emulate_step"); > if (!op_callback_addr || !emulate_step_addr) { > WARN(1, "kprobe_lookup_name() failed\n"); > goto error; > diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h > index c328e4f7dcad..16f153c84646 100644 > --- a/include/linux/kprobes.h > +++ b/include/linux/kprobes.h > @@ -379,6 +379,7 @@ static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void) > return this_cpu_ptr(&kprobe_ctlblk); > } > > +kprobe_opcode_t *kprobe_lookup_name(const char *name); > int register_kprobe(struct kprobe *p); > void unregister_kprobe(struct kprobe *p); > int register_kprobes(struct kprobe **kps, int num); > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > index 699c5bc51a92..f3421b6b47a3 100644 > --- a/kernel/kprobes.c > +++ b/kernel/kprobes.c > @@ -58,15 +58,6 @@ > #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS) > > > -/* > - * Some oddball architectures like 64bit powerpc have function descriptors > - * so this must be overridable. > - */ > -#ifndef kprobe_lookup_name > -#define kprobe_lookup_name(name, addr) \ > - addr = ((kprobe_opcode_t *)(kallsyms_lookup_name(name))) > -#endif > - > static int kprobes_initialized; > static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE]; > static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; > @@ -81,6 +72,11 @@ static struct { > raw_spinlock_t lock ____cacheline_aligned_in_smp; > } kretprobe_table_locks[KPROBE_TABLE_SIZE]; > > +kprobe_opcode_t * __weak kprobe_lookup_name(const char *name) > +{ > + return ((kprobe_opcode_t *)(kallsyms_lookup_name(name))); > +} > + > static raw_spinlock_t *kretprobe_table_lock_ptr(unsigned long hash) > { > return &(kretprobe_table_locks[hash].lock); > @@ -1400,7 +1396,7 @@ static kprobe_opcode_t *kprobe_addr(struct kprobe *p) > goto invalid; > > if (p->symbol_name) { > - kprobe_lookup_name(p->symbol_name, addr); > + addr = kprobe_lookup_name(p->symbol_name); > if (!addr) > return ERR_PTR(-ENOENT); > } > @@ -2192,8 +2188,8 @@ static int __init init_kprobes(void) > if (kretprobe_blacklist_size) { > /* lookup the function address from its name */ > for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { > - kprobe_lookup_name(kretprobe_blacklist[i].name, > - kretprobe_blacklist[i].addr); > + kretprobe_blacklist[i].addr = > + kprobe_lookup_name(kretprobe_blacklist[i].name); > if (!kretprobe_blacklist[i].addr) > printk("kretprobe: lookup failed: %s\n", > kretprobe_blacklist[i].name); > -- > 2.12.1 >
From: Naveen N. Rao > Sent: 12 April 2017 11:58 ... > +kprobe_opcode_t *kprobe_lookup_name(const char *name) > +{ ... > + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; > + const char *modsym; > + bool dot_appended = false; > + if ((modsym = strchr(name, ':')) != NULL) { > + modsym++; > + if (*modsym != '\0' && *modsym != '.') { > + /* Convert to <module:.symbol> */ > + strncpy(dot_name, name, modsym - name); > + dot_name[modsym - name] = '.'; > + dot_name[modsym - name + 1] = '\0'; > + strncat(dot_name, modsym, > + sizeof(dot_name) - (modsym - name) - 2); > + dot_appended = true; If the ':' is 'a way down' name[] then although the strncpy() won't overrun dot_name[] the rest of the code can. The strncat() call is particularly borked. David
Excerpts from David Laight's message of April 18, 2017 18:22: > From: Naveen N. Rao >> Sent: 12 April 2017 11:58 > ... >> +kprobe_opcode_t *kprobe_lookup_name(const char *name) >> +{ > ... >> + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; >> + const char *modsym; >> + bool dot_appended = false; >> + if ((modsym = strchr(name, ':')) != NULL) { >> + modsym++; >> + if (*modsym != '\0' && *modsym != '.') { >> + /* Convert to <module:.symbol> */ >> + strncpy(dot_name, name, modsym - name); >> + dot_name[modsym - name] = '.'; >> + dot_name[modsym - name + 1] = '\0'; >> + strncat(dot_name, modsym, >> + sizeof(dot_name) - (modsym - name) - 2); >> + dot_appended = true; > > If the ':' is 'a way down' name[] then although the strncpy() won't > overrun dot_name[] the rest of the code can. Nice catch, thanks David! We need to be validating the length of 'name'. I'll put out a patch for that. As an aside, I'm not sure I follow what you mean when you say that the strncpy() won't overrun dot_name[]. If we have a name[] longer than sizeof(dot_name) with the ':' after that, the strncpy() can also overrun dot_name[]. - Naveen > > The strncat() call is particularly borked. > > David > >
From: Naveen N. Rao > Sent: 19 April 2017 09:09 > To: David Laight; Michael Ellerman > Cc: linux-kernel@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; Masami Hiramatsu; Ingo Molnar > Subject: RE: [PATCH v2 1/5] kprobes: convert kprobe_lookup_name() to a function > > Excerpts from David Laight's message of April 18, 2017 18:22: > > From: Naveen N. Rao > >> Sent: 12 April 2017 11:58 > > ... > >> +kprobe_opcode_t *kprobe_lookup_name(const char *name) > >> +{ > > ... > >> + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; > >> + const char *modsym; > >> + bool dot_appended = false; > >> + if ((modsym = strchr(name, ':')) != NULL) { > >> + modsym++; > >> + if (*modsym != '\0' && *modsym != '.') { > >> + /* Convert to <module:.symbol> */ > >> + strncpy(dot_name, name, modsym - name); > >> + dot_name[modsym - name] = '.'; > >> + dot_name[modsym - name + 1] = '\0'; > >> + strncat(dot_name, modsym, > >> + sizeof(dot_name) - (modsym - name) - 2); > >> + dot_appended = true; > > > > If the ':' is 'a way down' name[] then although the strncpy() won't > > overrun dot_name[] the rest of the code can. > > Nice catch, thanks David! > We need to be validating the length of 'name'. I'll put out a patch for > that. Silent truncation is almost certainly wrong here. > As an aside, I'm not sure I follow what you mean when you say that the > strncpy() won't overrun dot_name[]. If we have a name[] longer than > sizeof(dot_name) with the ':' after that, the strncpy() can also overrun > dot_name[]. Yes, that should just be a memcpy(), as should the strncat(). Using strncpy() where the length is other than the size of the target buffer should be banned. Not that it ever does what people expect. strncat() is even worse. David
On 2017/04/19 08:48AM, David Laight wrote: > From: Naveen N. Rao > > Sent: 19 April 2017 09:09 > > To: David Laight; Michael Ellerman > > Cc: linux-kernel@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; Masami Hiramatsu; Ingo Molnar > > Subject: RE: [PATCH v2 1/5] kprobes: convert kprobe_lookup_name() to a function > > > > Excerpts from David Laight's message of April 18, 2017 18:22: > > > From: Naveen N. Rao > > >> Sent: 12 April 2017 11:58 > > > ... > > >> +kprobe_opcode_t *kprobe_lookup_name(const char *name) > > >> +{ > > > ... > > >> + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; > > >> + const char *modsym; > > >> + bool dot_appended = false; > > >> + if ((modsym = strchr(name, ':')) != NULL) { > > >> + modsym++; > > >> + if (*modsym != '\0' && *modsym != '.') { > > >> + /* Convert to <module:.symbol> */ > > >> + strncpy(dot_name, name, modsym - name); > > >> + dot_name[modsym - name] = '.'; > > >> + dot_name[modsym - name + 1] = '\0'; > > >> + strncat(dot_name, modsym, > > >> + sizeof(dot_name) - (modsym - name) - 2); > > >> + dot_appended = true; > > > > > > If the ':' is 'a way down' name[] then although the strncpy() won't > > > overrun dot_name[] the rest of the code can. > > > > Nice catch, thanks David! > > We need to be validating the length of 'name'. I'll put out a patch for > > that. > > Silent truncation is almost certainly wrong here. Indeed. This will be handled by the earlier validation to ensure that the module name as well as the symbol name are within the expected lengths. > > > As an aside, I'm not sure I follow what you mean when you say that the > > strncpy() won't overrun dot_name[]. If we have a name[] longer than > > sizeof(dot_name) with the ':' after that, the strncpy() can also overrun > > dot_name[]. > > Yes, that should just be a memcpy(), as should the strncat(). > > Using strncpy() where the length is other than the size of the target buffer > should be banned. Not that it ever does what people expect. > strncat() is even worse. Sure, but with the proper validation, I still think string functions are convenient and useful here. I agree about your view on strncat(), so I'll switch to strlcat() instead. Thanks, Naveen
diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h index 0503c98b2117..a843884aafaf 100644 --- a/arch/powerpc/include/asm/kprobes.h +++ b/arch/powerpc/include/asm/kprobes.h @@ -61,59 +61,6 @@ extern kprobe_opcode_t optprobe_template_end[]; #define MAX_OPTINSN_SIZE (optprobe_template_end - optprobe_template_entry) #define RELATIVEJUMP_SIZE sizeof(kprobe_opcode_t) /* 4 bytes */ -#ifdef PPC64_ELF_ABI_v2 -/* PPC64 ABIv2 needs local entry point */ -#define kprobe_lookup_name(name, addr) \ -{ \ - addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ - if (addr) \ - addr = (kprobe_opcode_t *)ppc_function_entry(addr); \ -} -#elif defined(PPC64_ELF_ABI_v1) -/* - * 64bit powerpc ABIv1 uses function descriptors: - * - Check for the dot variant of the symbol first. - * - If that fails, try looking up the symbol provided. - * - * This ensures we always get to the actual symbol and not the descriptor. - * Also handle <module:symbol> format. - */ -#define kprobe_lookup_name(name, addr) \ -{ \ - char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; \ - const char *modsym; \ - bool dot_appended = false; \ - if ((modsym = strchr(name, ':')) != NULL) { \ - modsym++; \ - if (*modsym != '\0' && *modsym != '.') { \ - /* Convert to <module:.symbol> */ \ - strncpy(dot_name, name, modsym - name); \ - dot_name[modsym - name] = '.'; \ - dot_name[modsym - name + 1] = '\0'; \ - strncat(dot_name, modsym, \ - sizeof(dot_name) - (modsym - name) - 2);\ - dot_appended = true; \ - } else { \ - dot_name[0] = '\0'; \ - strncat(dot_name, name, sizeof(dot_name) - 1); \ - } \ - } else if (name[0] != '.') { \ - dot_name[0] = '.'; \ - dot_name[1] = '\0'; \ - strncat(dot_name, name, KSYM_NAME_LEN - 2); \ - dot_appended = true; \ - } else { \ - dot_name[0] = '\0'; \ - strncat(dot_name, name, KSYM_NAME_LEN - 1); \ - } \ - addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \ - if (!addr && dot_appended) { \ - /* Let's try the original non-dot symbol lookup */ \ - addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ - } \ -} -#endif - #define flush_insn_slot(p) do { } while (0) #define kretprobe_blacklist_size 0 diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 331751701fed..a7aa7394954d 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -42,6 +42,64 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); struct kretprobe_blackpoint kretprobe_blacklist[] = {{NULL, NULL}}; +kprobe_opcode_t *kprobe_lookup_name(const char *name) +{ + kprobe_opcode_t *addr; + +#ifdef PPC64_ELF_ABI_v2 + /* PPC64 ABIv2 needs local entry point */ + addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); + if (addr) + addr = (kprobe_opcode_t *)ppc_function_entry(addr); +#elif defined(PPC64_ELF_ABI_v1) + /* + * 64bit powerpc ABIv1 uses function descriptors: + * - Check for the dot variant of the symbol first. + * - If that fails, try looking up the symbol provided. + * + * This ensures we always get to the actual symbol and not + * the descriptor. + * + * Also handle <module:symbol> format. + */ + char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; + const char *modsym; + bool dot_appended = false; + if ((modsym = strchr(name, ':')) != NULL) { + modsym++; + if (*modsym != '\0' && *modsym != '.') { + /* Convert to <module:.symbol> */ + strncpy(dot_name, name, modsym - name); + dot_name[modsym - name] = '.'; + dot_name[modsym - name + 1] = '\0'; + strncat(dot_name, modsym, + sizeof(dot_name) - (modsym - name) - 2); + dot_appended = true; + } else { + dot_name[0] = '\0'; + strncat(dot_name, name, sizeof(dot_name) - 1); + } + } else if (name[0] != '.') { + dot_name[0] = '.'; + dot_name[1] = '\0'; + strncat(dot_name, name, KSYM_NAME_LEN - 2); + dot_appended = true; + } else { + dot_name[0] = '\0'; + strncat(dot_name, name, KSYM_NAME_LEN - 1); + } + addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); + if (!addr && dot_appended) { + /* Let's try the original non-dot symbol lookup */ + addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); + } +#else + addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); +#endif + + return addr; +} + int __kprobes arch_prepare_kprobe(struct kprobe *p) { int ret = 0; diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c index 2282bf4e63cd..aefe076d00e0 100644 --- a/arch/powerpc/kernel/optprobes.c +++ b/arch/powerpc/kernel/optprobes.c @@ -243,8 +243,8 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p) /* * 2. branch to optimized_callback() and emulate_step() */ - kprobe_lookup_name("optimized_callback", op_callback_addr); - kprobe_lookup_name("emulate_step", emulate_step_addr); + op_callback_addr = kprobe_lookup_name("optimized_callback"); + emulate_step_addr = kprobe_lookup_name("emulate_step"); if (!op_callback_addr || !emulate_step_addr) { WARN(1, "kprobe_lookup_name() failed\n"); goto error; diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index c328e4f7dcad..16f153c84646 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -379,6 +379,7 @@ static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void) return this_cpu_ptr(&kprobe_ctlblk); } +kprobe_opcode_t *kprobe_lookup_name(const char *name); int register_kprobe(struct kprobe *p); void unregister_kprobe(struct kprobe *p); int register_kprobes(struct kprobe **kps, int num); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 699c5bc51a92..f3421b6b47a3 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -58,15 +58,6 @@ #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS) -/* - * Some oddball architectures like 64bit powerpc have function descriptors - * so this must be overridable. - */ -#ifndef kprobe_lookup_name -#define kprobe_lookup_name(name, addr) \ - addr = ((kprobe_opcode_t *)(kallsyms_lookup_name(name))) -#endif - static int kprobes_initialized; static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE]; static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; @@ -81,6 +72,11 @@ static struct { raw_spinlock_t lock ____cacheline_aligned_in_smp; } kretprobe_table_locks[KPROBE_TABLE_SIZE]; +kprobe_opcode_t * __weak kprobe_lookup_name(const char *name) +{ + return ((kprobe_opcode_t *)(kallsyms_lookup_name(name))); +} + static raw_spinlock_t *kretprobe_table_lock_ptr(unsigned long hash) { return &(kretprobe_table_locks[hash].lock); @@ -1400,7 +1396,7 @@ static kprobe_opcode_t *kprobe_addr(struct kprobe *p) goto invalid; if (p->symbol_name) { - kprobe_lookup_name(p->symbol_name, addr); + addr = kprobe_lookup_name(p->symbol_name); if (!addr) return ERR_PTR(-ENOENT); } @@ -2192,8 +2188,8 @@ static int __init init_kprobes(void) if (kretprobe_blacklist_size) { /* lookup the function address from its name */ for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { - kprobe_lookup_name(kretprobe_blacklist[i].name, - kretprobe_blacklist[i].addr); + kretprobe_blacklist[i].addr = + kprobe_lookup_name(kretprobe_blacklist[i].name); if (!kretprobe_blacklist[i].addr) printk("kretprobe: lookup failed: %s\n", kretprobe_blacklist[i].name);
The macro is now pretty long and ugly on powerpc. In the light of further changes needed here, convert it to a __weak variant to be over-ridden with a nicer looking function. Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> --- arch/powerpc/include/asm/kprobes.h | 53 ---------------------------------- arch/powerpc/kernel/kprobes.c | 58 ++++++++++++++++++++++++++++++++++++++ arch/powerpc/kernel/optprobes.c | 4 +-- include/linux/kprobes.h | 1 + kernel/kprobes.c | 20 ++++++------- 5 files changed, 69 insertions(+), 67 deletions(-)