diff options
| author | Song Liu <song@kernel.org> | 2025-03-27 11:55:28 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-04-02 21:55:43 -0700 |
| commit | 00387808d36e23c7d56e9e04a31de0be1443b0e9 (patch) | |
| tree | 7e66ce063840256aa714fceb3f2fc5087aac26aa | |
| parent | 5d0b204654de25615cf712be86c3192eca68ed80 (diff) | |
selftests/bpf: Fix tests after fields reorder in struct file
The change in struct file [1] moved f_ref to the 3rd cache line.
It made *(u64 *)file dereference invalid from the verifier point of view,
because btf_struct_walk() walks into f_lock field, which is 4-byte long.
Fix the selftests to deference the file pointer as a 4-byte access.
[1] commit e249056c91a2 ("fs: place f_ref to 3rd cache line in struct file to resolve false sharing")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20250327185528.1740787-1-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_module_attach.c | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_subprogs_extable.c | 6 |
2 files changed, 4 insertions, 4 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_module_attach.c b/tools/testing/selftests/bpf/progs/test_module_attach.c index fb07f5773888..7f3c233943b3 100644 --- a/tools/testing/selftests/bpf/progs/test_module_attach.c +++ b/tools/testing/selftests/bpf/progs/test_module_attach.c @@ -117,7 +117,7 @@ int BPF_PROG(handle_fexit_ret, int arg, struct file *ret) bpf_probe_read_kernel(&buf, 8, ret); bpf_probe_read_kernel(&buf, 8, (char *)ret + 256); - *(volatile long long *)ret; + *(volatile int *)ret; *(volatile int *)&ret->f_mode; return 0; } diff --git a/tools/testing/selftests/bpf/progs/test_subprogs_extable.c b/tools/testing/selftests/bpf/progs/test_subprogs_extable.c index e2a21fbd4e44..dcac69f5928a 100644 --- a/tools/testing/selftests/bpf/progs/test_subprogs_extable.c +++ b/tools/testing/selftests/bpf/progs/test_subprogs_extable.c @@ -21,7 +21,7 @@ static __u64 test_cb(struct bpf_map *map, __u32 *key, __u64 *val, void *data) SEC("fexit/bpf_testmod_return_ptr") int BPF_PROG(handle_fexit_ret_subprogs, int arg, struct file *ret) { - *(volatile long *)ret; + *(volatile int *)ret; *(volatile int *)&ret->f_mode; bpf_for_each_map_elem(&test_array, test_cb, NULL, 0); triggered++; @@ -31,7 +31,7 @@ int BPF_PROG(handle_fexit_ret_subprogs, int arg, struct file *ret) SEC("fexit/bpf_testmod_return_ptr") int BPF_PROG(handle_fexit_ret_subprogs2, int arg, struct file *ret) { - *(volatile long *)ret; + *(volatile int *)ret; *(volatile int *)&ret->f_mode; bpf_for_each_map_elem(&test_array, test_cb, NULL, 0); triggered++; @@ -41,7 +41,7 @@ int BPF_PROG(handle_fexit_ret_subprogs2, int arg, struct file *ret) SEC("fexit/bpf_testmod_return_ptr") int BPF_PROG(handle_fexit_ret_subprogs3, int arg, struct file *ret) { - *(volatile long *)ret; + *(volatile int *)ret; *(volatile int *)&ret->f_mode; bpf_for_each_map_elem(&test_array, test_cb, NULL, 0); triggered++; |