From 90b271fbd2b9708a8fa79b7e98d90c7919e7ed73 Mon Sep 17 00:00:00 2001 From: Emil Velikov Date: Mon, 12 Feb 2024 17:23:05 +0000 Subject: [PATCH] libkmod: clear file->memory if map fails On mmap failure file->memory is set to -1, which we'll happily pass down to munmap later on. More importantly, since we do a NULL check in kmod_file_load_contents() we will exit the function without (re)attempting the load again. Since we ignore the return code for the load function(s), one can end up calling kmod_elf_get_memory() and feed that -1 into init_module. Signed-off-by: Emil Velikov Reviewed-by: Lucas De Marchi Signed-off-by: Lucas De Marchi --- libkmod/libkmod-file.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/libkmod/libkmod-file.c b/libkmod/libkmod-file.c index abd4723b..b408aed2 100644 --- a/libkmod/libkmod-file.c +++ b/libkmod/libkmod-file.c @@ -392,8 +392,10 @@ static int load_reg(struct kmod_file *file) file->size = st.st_size; file->memory = mmap(NULL, file->size, PROT_READ, MAP_PRIVATE, file->fd, 0); - if (file->memory == MAP_FAILED) + if (file->memory == MAP_FAILED) { + file->memory = NULL; return -errno; + } return 0; } -- 2.47.3