From 3b27d13940c3710a1128527c43719cb0bb05d73b Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Tue, 1 Sep 2015 03:29:44 +0000 Subject: [PATCH] perf dwarf: Fix potential array out of bounds access There is a problem in the dwarf-regs.c files for sh, sparc and x86 where it is possible to make an out-of-bounds array access when searching for register names. This patch fixes it by replacing '<=' to '<', so when register (number == XXX_MAX_REGS), get_arch_regstr() will return NULL. Signed-off-by: Wang Nan Reviewed-by: Matt Fleming Acked-by: Jiri Olsa Acked-by: Masami Hiramatsu Cc: David S. Miller Cc: Zefan Li Cc: pi3orama@huawei.com Link: http://lkml.kernel.org/r/1441078184-105038-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/sh/util/dwarf-regs.c | 2 +- tools/perf/arch/sparc/util/dwarf-regs.c | 2 +- tools/perf/arch/x86/util/dwarf-regs.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/perf/arch/sh/util/dwarf-regs.c b/tools/perf/arch/sh/util/dwarf-regs.c index 0d0897f57a10..f8dfa89696f4 100644 --- a/tools/perf/arch/sh/util/dwarf-regs.c +++ b/tools/perf/arch/sh/util/dwarf-regs.c @@ -51,5 +51,5 @@ const char *sh_regs_table[SH_MAX_REGS] = { /* Return architecture dependent register string (for kprobe-tracer) */ const char *get_arch_regstr(unsigned int n) { - return (n <= SH_MAX_REGS) ? sh_regs_table[n] : NULL; + return (n < SH_MAX_REGS) ? sh_regs_table[n] : NULL; } diff --git a/tools/perf/arch/sparc/util/dwarf-regs.c b/tools/perf/arch/sparc/util/dwarf-regs.c index 92eda412fed3..b704fdb9237a 100644 --- a/tools/perf/arch/sparc/util/dwarf-regs.c +++ b/tools/perf/arch/sparc/util/dwarf-regs.c @@ -39,5 +39,5 @@ const char *sparc_regs_table[SPARC_MAX_REGS] = { */ const char *get_arch_regstr(unsigned int n) { - return (n <= SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL; + return (n < SPARC_MAX_REGS) ? sparc_regs_table[n] : NULL; } diff --git a/tools/perf/arch/x86/util/dwarf-regs.c b/tools/perf/arch/x86/util/dwarf-regs.c index be22dd463232..a08de0a35b83 100644 --- a/tools/perf/arch/x86/util/dwarf-regs.c +++ b/tools/perf/arch/x86/util/dwarf-regs.c @@ -71,5 +71,5 @@ const char *x86_64_regs_table[X86_64_MAX_REGS] = { /* Return architecture dependent register string (for kprobe-tracer) */ const char *get_arch_regstr(unsigned int n) { - return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL; + return (n < ARCH_MAX_REGS) ? arch_regs_table[n] : NULL; }