6.6-stable review patch. If anyone has any objections, please let me know.
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From: Binbin Wu binbin.wu@linux.intel.com
[ Upstream commit 29060633411a02f6f2dd9d5245919385d69d81f0 ]
Zero out the buffer for readlink() since readlink() does not append a terminating null byte to the buffer. Also change the buffer length passed to readlink() to 'PATH_MAX - 1' to ensure the resulting string is always null terminated.
Fixes: 833c12ce0f430 ("selftests/x86/lam: Add inherit test cases for linear-address masking") Signed-off-by: Binbin Wu binbin.wu@linux.intel.com Signed-off-by: Ingo Molnar mingo@kernel.org Reviewed-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/r/20231016062446.695-1-binbin.wu@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/x86/lam.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/x86/lam.c b/tools/testing/selftests/x86/lam.c index eb0e46905bf9d..8f9b06d9ce039 100644 --- a/tools/testing/selftests/x86/lam.c +++ b/tools/testing/selftests/x86/lam.c @@ -573,7 +573,7 @@ int do_uring(unsigned long lam) char path[PATH_MAX] = {0};
/* get current process path */ - if (readlink("/proc/self/exe", path, PATH_MAX) <= 0) + if (readlink("/proc/self/exe", path, PATH_MAX - 1) <= 0) return 1;
int file_fd = open(path, O_RDONLY); @@ -680,14 +680,14 @@ static int handle_execve(struct testcases *test) perror("Fork failed."); ret = 1; } else if (pid == 0) { - char path[PATH_MAX]; + char path[PATH_MAX] = {0};
/* Set LAM mode in parent process */ if (set_lam(lam) != 0) return 1;
/* Get current binary's path and the binary was run by execve */ - if (readlink("/proc/self/exe", path, PATH_MAX) <= 0) + if (readlink("/proc/self/exe", path, PATH_MAX - 1) <= 0) exit(-1);
/* run binary to get LAM mode and return to parent process */