On Tue, Nov 05, 2024 at 10:19:11AM -0800, Kees Cook wrote: > Attempting to free an ERR_PTR will not work. ;) > > process 'syz-executor210' launched '/dev/fd/3' with NULL argv: empty string added > kernel BUG at arch/x86/mm/physaddr.c:23! > > Set bprm->argv0 to NULL if it fails to get a string from userspace so > that bprm_free() will not try to free an invalid pointer when cleaning up. > > Reported-by: syzbot+03e1af5c332f7e0eb84b@xxxxxxxxxxxxxxxxxxxxxxxxx > Closes: https://lore.kernel.org/all/6729d8d1.050a0220.701a.0017.GAE@xxxxxxxxxx > Fixes: 7bdc6fc85c9a ("exec: fix up /proc/pid/comm in the execveat(AT_EMPTY_PATH) case") > Signed-off-by: Kees Cook <kees@xxxxxxxxxx> > --- > Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> > Cc: Christian Brauner <brauner@xxxxxxxxxx> > Cc: Jan Kara <jack@xxxxxxx> > Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx> > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> -- Kiryl Shutsemau / Kirill A. Shutemov
