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| author | Xu Kuohai <xukuohai@huawei.com> | 2022-10-11 14:01:04 +0200 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2022-10-13 19:53:18 +0200 |
| commit | 0dc9254e03704c75f2ebc9cbef2ce4de83fba603 (patch) | |
| tree | 9241bdca95d8ad1589961a09e182f3e97a199567 /tools/lib/bpf/usdt.c | |
| parent | libbpf: Fix use-after-free in btf_dump_name_dups (diff) | |
| download | linux-0dc9254e03704c75f2ebc9cbef2ce4de83fba603.tar.xz linux-0dc9254e03704c75f2ebc9cbef2ce4de83fba603.zip | |
libbpf: Fix memory leak in parse_usdt_arg()
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
Diffstat (limited to 'tools/lib/bpf/usdt.c')
| -rw-r--r-- | tools/lib/bpf/usdt.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/tools/lib/bpf/usdt.c b/tools/lib/bpf/usdt.c index e83b497c2245..49f3c3b7f609 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; |