diff options
Diffstat (limited to 'kernel/hw_breakpoint.c')
| -rw-r--r-- | kernel/hw_breakpoint.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index 9ed9ae3a48b3..89e8a050c43a 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -308,6 +308,28 @@ int dbg_release_bp_slot(struct perf_event *bp) return 0; } +static int validate_hw_breakpoint(struct perf_event *bp) +{ + int ret; + + ret = arch_validate_hwbkpt_settings(bp); + if (ret) + return ret; + + if (arch_check_bp_in_kernelspace(bp)) { + if (bp->attr.exclude_kernel) + return -EINVAL; + /* + * Don't let unprivileged users set a breakpoint in the trap + * path to avoid trap recursion attacks. + */ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + } + + return 0; +} + int register_perf_hw_breakpoint(struct perf_event *bp) { int ret; @@ -316,7 +338,7 @@ int register_perf_hw_breakpoint(struct perf_event *bp) if (ret) return ret; - ret = arch_validate_hwbkpt_settings(bp, bp->ctx->task); + ret = validate_hw_breakpoint(bp); /* if arch_validate_hwbkpt_settings() fails then release bp slot */ if (ret) @@ -363,7 +385,7 @@ int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *att if (attr->disabled) goto end; - err = arch_validate_hwbkpt_settings(bp, bp->ctx->task); + err = validate_hw_breakpoint(bp); if (!err) perf_event_enable(bp); |