Messages in this thread Patch in this message | | | From | kan.liang@linux ... | Subject | [PATCH 2/2] perf/x86/regs: Check reserved bits | Date | Thu, 23 May 2019 11:36:56 -0700 |
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From: Kan Liang <kan.liang@linux.intel.com>
The perf fuzzer triggers a warning which map to:
if (WARN_ON_ONCE(idx >= ARRAY_SIZE(pt_regs_offset))) return 0;
The bits between XMM registers and generic registers are reserved. But perf_reg_validate() doesn't check these bits.
Add REG_RESERVED for reserved bits. Check the reserved bits in perf_reg_validate().
Fixes: 878068ea270e ("perf/x86: Support outputting XMM registers") Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> --- arch/x86/kernel/perf_regs.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c index 86ffe5a..3f8c1fc 100644 --- a/arch/x86/kernel/perf_regs.c +++ b/arch/x86/kernel/perf_regs.c @@ -79,6 +79,9 @@ u64 perf_reg_value(struct pt_regs *regs, int idx) return regs_get_register(regs, pt_regs_offset[idx]); } +#define REG_RESERVED (((1ULL << PERF_REG_X86_XMM0) - 1) & \ + ~((1ULL << PERF_REG_X86_MAX) - 1)) + #ifdef CONFIG_X86_32 #define REG_NOSUPPORT ((1ULL << PERF_REG_X86_R8) | \ (1ULL << PERF_REG_X86_R9) | \ @@ -91,7 +94,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx) int perf_reg_validate(u64 mask) { - if (!mask || (mask & REG_NOSUPPORT)) + if (!mask || (mask & (REG_NOSUPPORT | REG_RESERVED))) return -EINVAL; return 0; @@ -117,7 +120,7 @@ void perf_get_regs_user(struct perf_regs *regs_user, int perf_reg_validate(u64 mask) { - if (!mask || (mask & REG_NOSUPPORT)) + if (!mask || (mask & (REG_NOSUPPORT | REG_RESERVED))) return -EINVAL; return 0; -- 2.7.4
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