| Message ID | 1381351883-8446-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/kernel/kmod.c b/kernel/kmod.c index 41e1524..6444887 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -560,6 +560,10 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait) DECLARE_COMPLETION_ONSTACK(done); int retval = 0; + if (!sub_info->path) { + call_usermodehelper_freeinfo(sub_info); + return -EINVAL; + } helper_lock(); if (!sub_info->path) { retval = -EINVAL;
This is a note to let you know that I have just added a patch titled kernel/kmod.c: check for NULL in call_usermodehelper_exec() to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.11. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From c40923662ca8a768b5c99a382179e9b28ca7ecab Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Date: Mon, 30 Sep 2013 13:45:08 -0700 Subject: kernel/kmod.c: check for NULL in call_usermodehelper_exec() commit 4c1c7be95c345cf2ad537a0c48e9aeadc7304527 upstream. If /proc/sys/kernel/core_pattern contains only "|", a NULL pointer dereference happens upon core dump because argv_split("") returns argv[0] == NULL. This bug was once fixed by commit 264b83c07a84 ("usermodehelper: check subprocess_info->path != NULL") but was by error reintroduced by commit 7f57cfa4e2aa ("usermodehelper: kill the sub_info->path[0] check"). This bug seems to exist since 2.6.19 (the version which core dump to pipe was added). Depending on kernel version and config, some side effect might happen immediately after this oops (e.g. kernel panic with 2.6.32-358.18.1.el6). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- kernel/kmod.c | 4 ++++ 1 file changed, 4 insertions(+) -- 1.8.1.2