From: Xu Kuohai xukuohai@huawei.com
[ Upstream commit 0dc9254e03704c75f2ebc9cbef2ce4de83fba603 ]
In the arm64 version of parse_usdt_arg(), when sscanf returns 2, reg_name is allocated but not freed. Fix it.
Fixes: 0f8619929c57 ("libbpf: Usdt aarch64 arg parsing support") Signed-off-by: Xu Kuohai xukuohai@huawei.com Signed-off-by: Andrii Nakryiko andrii@kernel.org Acked-by: Martin KaFai Lau martin.lau@kernel.org Link: https://lore.kernel.org/bpf/20221011120108.782373-3-xukuohai@huaweicloud.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/lib/bpf/usdt.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/tools/lib/bpf/usdt.c b/tools/lib/bpf/usdt.c index d18e37982344..2ade9c7969d7 100644 --- a/tools/lib/bpf/usdt.c +++ b/tools/lib/bpf/usdt.c @@ -1348,25 +1348,23 @@ static int calc_pt_regs_off(const char *reg_name)
static int parse_usdt_arg(const char *arg_str, int arg_num, struct usdt_arg_spec *arg) { - char *reg_name = NULL; + char reg_name[16]; int arg_sz, len, reg_off; long off;
- if (sscanf(arg_str, " %d @ [ %m[a-z0-9], %ld ] %n", &arg_sz, ®_name, &off, &len) == 3) { + if (sscanf(arg_str, " %d @ [ %15[a-z0-9], %ld ] %n", &arg_sz, reg_name, &off, &len) == 3) { /* Memory dereference case, e.g., -4@[sp, 96] */ arg->arg_type = USDT_ARG_REG_DEREF; arg->val_off = off; reg_off = calc_pt_regs_off(reg_name); - free(reg_name); if (reg_off < 0) return reg_off; arg->reg_off = reg_off; - } else if (sscanf(arg_str, " %d @ [ %m[a-z0-9] ] %n", &arg_sz, ®_name, &len) == 2) { + } else if (sscanf(arg_str, " %d @ [ %15[a-z0-9] ] %n", &arg_sz, reg_name, &len) == 2) { /* Memory dereference case, e.g., -4@[sp] */ arg->arg_type = USDT_ARG_REG_DEREF; arg->val_off = 0; reg_off = calc_pt_regs_off(reg_name); - free(reg_name); if (reg_off < 0) return reg_off; arg->reg_off = reg_off; @@ -1375,12 +1373,11 @@ static int parse_usdt_arg(const char *arg_str, int arg_num, struct usdt_arg_spec arg->arg_type = USDT_ARG_CONST; arg->val_off = off; arg->reg_off = 0; - } else if (sscanf(arg_str, " %d @ %m[a-z0-9] %n", &arg_sz, ®_name, &len) == 2) { + } else if (sscanf(arg_str, " %d @ %15[a-z0-9] %n", &arg_sz, reg_name, &len) == 2) { /* Register read case, e.g., -8@x4 */ arg->arg_type = USDT_ARG_REG; arg->val_off = 0; reg_off = calc_pt_regs_off(reg_name); - free(reg_name); if (reg_off < 0) return reg_off; arg->reg_off = reg_off;