(2014/06/20 16:34), Jianyu Zhan wrote: > Hi, I found that this patch wasn't merged into mainline during this merge > window(maybe it wasn't cooked in any tree), while it has been acked-by for > a couple of days. > > Ingo, would you mind queueing this one? Thanks.
Ping? I've already acked this. > > -----<8----- > > Currently, if user specifies both symbol name and address, we just > bail out. > > This might be too rude. This patch makes it give more tolerance. > If both are specified, check address first, if the symbol found > does not match the one user specify, print a waring. If not found, > return -ENOENT, because some symbols might have muplitple instances, > we don't bother to check symbol name. > > Acked-by: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> > Signed-off-by: Jianyu Zhan <nasa4...@gmail.com> > --- > Documentation/kprobes.txt | 4 +++- > kernel/kprobes.c | 32 +++++++++++++++++++++++++++++--- > 2 files changed, 32 insertions(+), 4 deletions(-) > > diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt > index 4bbeca8..49af14e 100644 > --- a/Documentation/kprobes.txt > +++ b/Documentation/kprobes.txt > @@ -358,7 +358,9 @@ to install a probepoint is known. This field is used to > calculate the > probepoint. > > 3. Specify either the kprobe "symbol_name" OR the "addr". If both are > -specified, kprobe registration will fail with -EINVAL. > +specified, only check "addr", because some symbols might have muplitple > +instances. If neither is specified, kprobe registration will fail > +with -EINVAL. > > 4. With CISC architectures (such as i386 and x86_64), the kprobes code > does not validate if the kprobe.addr is at an instruction boundary. > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > index 3214289..81d891b 100644 > --- a/kernel/kprobes.c > +++ b/kernel/kprobes.c > @@ -1358,15 +1358,41 @@ static bool within_kprobe_blacklist(unsigned long > addr) > static kprobe_opcode_t *kprobe_addr(struct kprobe *p) > { > kprobe_opcode_t *addr = p->addr; > + char namebuf[KSYM_NAME_LEN]; > + const char *sym_name = NULL; > + unsigned long offset; > > - if ((p->symbol_name && p->addr) || > - (!p->symbol_name && !p->addr)) > + if (!p->symbol_name && !p->addr) > goto invalid; > > - if (p->symbol_name) { > + /* > + * Some symbols might have muplitple instances, > + * so if both specified, only check address. > + */ > + if (unlikely(p->addr && p->symbol_name)) { > + sym_name = kallsyms_lookup((unsigned long)(p->addr), > + NULL, &offset, NULL, namebuf); > + if (!sym_name) > + return ERR_PTR(-ENOENT); > + > + if (strncmp(sym_name, p->symbol_name, KSYM_NAME_LEN) > + || offset != p->offset) { > + pr_err("Incorrect symbol or offset, should be " > + "symbol=%s, offset=%ld.\n", sym_name, offset); > + goto invalid; > + } > + } else if (p->symbol_name) { > + /* Only symbol case */ > kprobe_lookup_name(p->symbol_name, addr); > if (!addr) > return ERR_PTR(-ENOENT); > + } else { > + /* > + * Only address case. > + * Since we later will do sanity check of the > + * address range in check_kprobe_address_safe(), > + * do nothing here. > + */ > } > > addr = (kprobe_opcode_t *)(((char *)addr) + p->offset); > -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu...@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/