[PATCH] Fix infinite loop in search_binary_handler()
From: Richard Weinberger <richard@nod.at>
Date: 2011-06-16 22:11:20
Also in:
linux-fsdevel, lkml
Subsystem:
exec & binfmt api, elf, filesystems (vfs and infrastructure), the rest · Maintainers:
Kees Cook, Alexander Viro, Christian Brauner, Linus Torvalds
When search_binary_handler() is called to find a handler for /sbin/modprobe it will end up in an infinite loop because it executes request_module() to load a binfmt module with /sbin/modprobe... Running a x86_64 kernel without ia32 emulation and a x86 user land triggers this issue. Signed-off-by: Richard Weinberger <richard@nod.at> --- fs/exec.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index 97e0d52..7271b22 100644
--- a/fs/exec.c
+++ b/fs/exec.c@@ -1411,7 +1411,10 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) printable(bprm->buf[2]) && printable(bprm->buf[3])) break; /* -ENOEXEC */ - request_module("binfmt-%04x", *(unsigned short *)(&bprm->buf[2])); + + /* Avoid an infinite loop */ + if (strcmp(modprobe_path, bprm->filename)) + request_module("binfmt-%04x", *(unsigned short *)(&bprm->buf[2])); #endif } }
--
1.7.5.4