On 02/29/2016 02:26 PM, Michal Hocko wrote:
From: Michal Hocko <mho...@suse.com>
vm_brk is allowed to fail but load_aout_binary simply ignores the error
and happily continues. I haven't noticed any problem from that in real
life but later patches will make the failure more likely because
vm_brk will become killable (resp. mmap_sem for write waiting will become
killable) so we should be more careful now.
The error handling should be quite straightforward because there are
calls to vm_mmap which check the error properly already. The only
notable exception is set_brk which is called after beyond_if label.
But nothing indicates that we cannot move it above set_binfmt as the two
do not depend on each other and fail before we do set_binfmt and alter
reference counting.
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Alexander Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Michal Hocko <mho...@suse.com>
Acked--by: Vlastimil Babka <vba...@suse.cz>
[...]
@@ -378,7 +381,9 @@ static int load_aout_library(struct file *file)
"N_TXTOFF is not page aligned. Please convert
library: %pD\n",
file);
}
- vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
+ retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
+ if (IS_ERR_VALUE(retval))
+ goto out;
You could have removed the extra whitespace on the line above, which my vim so
prominently highlights :)
read_code(file, start_addr, N_TXTOFF(ex),
ex.a_text + ex.a_data);
