[ Upstream commit fd1f70776a ]
mount_overload() builds an environment variable name like
"PERF_SYSFS_ENVIRONMENT" from fs->name. Two bugs:
1) snprintf() uses name_len as the buffer size instead of sizeof(upper_name).
For fs->name = "sysfs" (len=5), the output is truncated to "PERF" (4
chars + null), so getenv() never finds the intended variable.
2) mem_toupper() only uppercases name_len bytes, converting just the "PERF"
prefix rather than the full string including the filesystem name portion.
Fix by using sizeof(upper_name) for snprintf and strlen(upper_name) for
mem_toupper, so the full "PERF_SYSFS_ENVIRONMENT" string is correctly
formatted and uppercased.
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Fixes: 73ca85ad36 ("tools lib api fs: Add FSTYPE__mount() method")
Cc: Jiri Olsa <jolsa@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
919c9c7933