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| author |   Mykyta Yatsenko <yatsenko@meta.com> | 2025-05-23 19:17:05 +0100 |
|---|---|---|
| committer |   Andrii Nakryiko <andrii@kernel.org> | 2025-05-23 13:25:02 -0700 |
| commit | 079e5c56a5c41d285068939ff7b0041ab10386fa (patch) | |
| tree | 564e2b77b6d0704b39d1d04e009586dfb8ebb0b8 /kernel | |
| parent | Merge branch 'allow-mmap-of-sys-kernel-btf-vmlinux' (diff) | |
| download | wireguard-linux-079e5c56a5c41d285068939ff7b0041ab10386fa.tar.xz wireguard-linux-079e5c56a5c41d285068939ff7b0041ab10386fa.zip | |
bpf: Fix error return value in bpf_copy_from_user_dynptr
On error, copy_from_user returns number of bytes not copied to
destination, but current implementation of copy_user_data_sleepable does
not handle that correctly and returns it as error value, which may
confuse user, expecting meaningful negative error value.
Fixes: a498ee7576de ("bpf: Implement dynptr copy kfuncs")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250523181705.261585-1-mykyta.yatsenko5@gmail.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 289ff0caa83e..132c8be6f635 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3555,8 +3555,12 @@ static __always_inline int copy_user_data_sleepable(void *dst, const void *unsaf { int ret; - if (!tsk) /* Read from the current task */ - return copy_from_user(dst, (const void __user *)unsafe_src, size); + if (!tsk) { /* Read from the current task */ + ret = copy_from_user(dst, (const void __user *)unsafe_src, size); + if (ret) + return -EFAULT; + return 0; + } ret = access_process_vm(tsk, (unsigned long)unsafe_src, dst, size, 0); if (ret != size) |