diff mbox series

[bpf-next,2/2] bpf: Call the missed kfree() when there is no special field in btf

Message ID 20240912012845.3458483-3-houtao@huaweicloud.com (mailing list archive)
State Accepted
Commit 986deb297d48ae7039ab975f00c14f0bfe069125
Delegated to: BPF
Headers show
Series Two tiny fixes for btf record | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 16 of 16 maintainers
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 18 this patch: 18
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 11 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-VM_Test-0 success Logs for Lint
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Unittests
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Validate matrix.py
bpf/vmtest-bpf-next-VM_Test-5 success Logs for aarch64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-4 success Logs for aarch64-gcc / build / build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for aarch64-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-12 success Logs for s390x-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-6 success Logs for aarch64-gcc / test (test_maps, false, 360) / test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for aarch64-gcc / test (test_progs, false, 360) / test_progs on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for aarch64-gcc / test (test_verifier, false, 360) / test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for s390x-gcc / build / build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for s390x-gcc / test (test_verifier, false, 360) / test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for s390x-gcc / veristat
bpf/vmtest-bpf-next-VM_Test-17 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-18 success Logs for x86_64-gcc / build / build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-19 success Logs for x86_64-gcc / build-release
bpf/vmtest-bpf-next-VM_Test-27 success Logs for x86_64-llvm-17 / build / build for x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-28 success Logs for x86_64-llvm-17 / build-release / build for x86_64 with llvm-17-O2
bpf/vmtest-bpf-next-VM_Test-34 success Logs for x86_64-llvm-18 / build / build for x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-35 success Logs for x86_64-llvm-18 / build-release / build for x86_64 with llvm-18-O2
bpf/vmtest-bpf-next-VM_Test-33 success Logs for x86_64-llvm-17 / veristat
bpf/vmtest-bpf-next-VM_Test-41 success Logs for x86_64-llvm-18 / veristat
bpf/vmtest-bpf-next-VM_Test-25 success Logs for x86_64-gcc / test (test_verifier, false, 360) / test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-14 success Logs for s390x-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for s390x-gcc / test (test_progs, false, 360) / test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-40 success Logs for x86_64-llvm-18 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-8 success Logs for aarch64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-32 success Logs for x86_64-llvm-17 / test (test_verifier, false, 360) / test_verifier on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-23 success Logs for x86_64-gcc / test (test_progs_no_alu32_parallel, true, 30) / test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for x86_64-gcc / test (test_maps, false, 360) / test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-30 success Logs for x86_64-llvm-17 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-24 success Logs for x86_64-gcc / test (test_progs_parallel, true, 30) / test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-22 success Logs for x86_64-gcc / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-21 success Logs for x86_64-gcc / test (test_progs, false, 360) / test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-31 success Logs for x86_64-llvm-17 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-37 success Logs for x86_64-llvm-18 / test (test_progs, false, 360) / test_progs on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-26 success Logs for x86_64-gcc / veristat / veristat on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-29 success Logs for x86_64-llvm-17 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-17
bpf/vmtest-bpf-next-VM_Test-39 success Logs for x86_64-llvm-18 / test (test_progs_no_alu32, false, 360) / test_progs_no_alu32 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-38 success Logs for x86_64-llvm-18 / test (test_progs_cpuv4, false, 360) / test_progs_cpuv4 on x86_64 with llvm-18
bpf/vmtest-bpf-next-VM_Test-36 success Logs for x86_64-llvm-18 / test (test_maps, false, 360) / test_maps on x86_64 with llvm-18

Commit Message

Hou Tao Sept. 12, 2024, 1:28 a.m. UTC 
From: Hou Tao <houtao1@huawei.com>

Call the missed kfree() in btf_parse_struct_metas() when there is no
special field in btf, otherwise will get the following kmemleak report:

unreferenced object 0xffff888101033620 (size 8):
  comm "test_progs", pid 604, jiffies 4295127011
  ......
  backtrace (crc e77dc444):
    [<00000000186f90f3>] kmemleak_alloc+0x4b/0x80
    [<00000000ac8e9c4d>] __kmalloc_cache_noprof+0x2a1/0x310
    [<00000000d99d68d6>] btf_new_fd+0x72d/0xe90
    [<00000000f010b7f8>] __sys_bpf+0xec3/0x2410
    [<00000000e077ed6f>] __x64_sys_bpf+0x1f/0x30
    [<00000000a12f9e55>] x64_sys_call+0x199/0x9f0
    [<00000000f3029ea6>] do_syscall_64+0x3b/0xc0
    [<000000005640913a>] entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: 7a851ecb1806 ("bpf: Search for kptrs in prog BTF structs")
Signed-off-by: Hou Tao <houtao1@huawei.com>
---
 kernel/bpf/btf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Jiri Olsa Sept. 12, 2024, 7:53 a.m. UTC | #1 
On Thu, Sep 12, 2024 at 09:28:45AM +0800, Hou Tao wrote:
> From: Hou Tao <houtao1@huawei.com>
> 
> Call the missed kfree() in btf_parse_struct_metas() when there is no
> special field in btf, otherwise will get the following kmemleak report:
> 
> unreferenced object 0xffff888101033620 (size 8):
>   comm "test_progs", pid 604, jiffies 4295127011
>   ......
>   backtrace (crc e77dc444):
>     [<00000000186f90f3>] kmemleak_alloc+0x4b/0x80
>     [<00000000ac8e9c4d>] __kmalloc_cache_noprof+0x2a1/0x310
>     [<00000000d99d68d6>] btf_new_fd+0x72d/0xe90
>     [<00000000f010b7f8>] __sys_bpf+0xec3/0x2410
>     [<00000000e077ed6f>] __x64_sys_bpf+0x1f/0x30
>     [<00000000a12f9e55>] x64_sys_call+0x199/0x9f0
>     [<00000000f3029ea6>] do_syscall_64+0x3b/0xc0
>     [<000000005640913a>] entry_SYSCALL_64_after_hwframe+0x4b/0x53
> 
> Fixes: 7a851ecb1806 ("bpf: Search for kptrs in prog BTF structs")
> Signed-off-by: Hou Tao <houtao1@huawei.com>
> ---
>  kernel/bpf/btf.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
> index 59b4f7265761..31eae516f701 100644
> --- a/kernel/bpf/btf.c
> +++ b/kernel/bpf/btf.c
> @@ -5572,8 +5572,10 @@ btf_parse_struct_metas(struct bpf_verifier_log *log, struct btf *btf)
>  		aof->ids[aof->cnt++] = i;
>  	}

I was wondering we could get away without the initial kmalloc and
let the first krealoc do the first allocation, but it might need
some other extra checks, so not sure it's worth it

in any case this lgtm

Acked-by: Jiri Olsa <jolsa@kernel.org>

jirka

>  
> -	if (!aof->cnt)
> +	if (!aof->cnt) {
> +		kfree(aof);
>  		return NULL;
> +	}
>  	sort(&aof->ids, aof->cnt, sizeof(aof->ids[0]), btf_id_cmp_func, NULL);
>  
>  	for (i = 1; i < n; i++) {
> -- 
> 2.29.2
>
diff mbox series

Patch

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 59b4f7265761..31eae516f701 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -5572,8 +5572,10 @@  btf_parse_struct_metas(struct bpf_verifier_log *log, struct btf *btf)
 		aof->ids[aof->cnt++] = i;
 	}
 
-	if (!aof->cnt)
+	if (!aof->cnt) {
+		kfree(aof);
 		return NULL;
+	}
 	sort(&aof->ids, aof->cnt, sizeof(aof->ids[0]), btf_id_cmp_func, NULL);
 
 	for (i = 1; i < n; i++) {