From: Sudip Mukherjee sudipm.mukherjee@gmail.com
commit db973a7289dad24e6c017dcedc6aee886579dc3a upstream.
If the core_pattern is set to "|" and any process segfaults then we get a null pointer derefernce while trying to coredump. The call stack shows:
RIP: do_coredump+0x628/0x11c0
When the core_pattern has only "|" there is no use of trying the coredump and we can check that while formating the corename and exit with an error.
After this change I get:
format_corename failed Aborting core
Fixes: 315c69261dd3 ("coredump: split pipe command whitespace before expanding template") Reported-by: Matthew Ruffell matthew.ruffell@canonical.com Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Cc: Paul Wise pabs3@bonedaddy.net Cc: Alexander Viro viro@zeniv.linux.org.uk Cc: Neil Horman nhorman@tuxdriver.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20200416194612.21418-1-sudipm.mukherjee@gmail.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/coredump.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/coredump.c +++ b/fs/coredump.c @@ -211,6 +211,8 @@ static int format_corename(struct core_n return -ENOMEM; (*argv)[(*argc)++] = 0; ++pat_ptr; + if (!(*pat_ptr)) + return -ENOMEM; }
/* Repeat as long as we have more pattern to process and more output