Commit 2ccd4f4d4737b37e21dd92c8c584c23cd87740a2
Committed by
Linus Torvalds
Linus Torvalds
1 parent
888a214dc4
Exists in
master
and in
20 other branches
pipe: fail cleanly when root tries F_SETPIPE_SZ with big size
When a user with the CAP_SYS_RESOURCE cap tries to F_SETPIPE_SZ a pipe
with size bigger than kmalloc() can alloc it spits out an ugly warning:
------------[ cut here ]------------
WARNING: at mm/page_alloc.c:2095 __alloc_pages_nodemask+0x5d3/0x7a0()
Pid: 733, comm: a.out Not tainted 3.2.0-rc1+ #4
Call Trace:
warn_slowpath_common+0x75/0xb0
warn_slowpath_null+0x15/0x20
__alloc_pages_nodemask+0x5d3/0x7a0
__get_free_pages+0x12/0x50
__kmalloc+0x12b/0x150
pipe_set_size+0x75/0x120
pipe_fcntl+0xf8/0x140
do_fcntl+0x2d4/0x410
sys_fcntl+0x66/0xa0
system_call_fastpath+0x16/0x1b
---[ end trace 432f702e6db7b5ee ]---
Instead, make kcalloc() handle the overflow case and fail quietly.
[akpm@linux-foundation.org: switch to sizeof(*bufs) for 80-column niceness]
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Acked-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 1 additions and 1 deletions Side-by-side Diff
fs/pipe.c
| ... | ... | @@ -1137,7 +1137,7 @@ |
| 1137 | 1137 | if (nr_pages < pipe->nrbufs) |
| 1138 | 1138 | return -EBUSY; |
| 1139 | 1139 | |
| 1140 | - bufs = kcalloc(nr_pages, sizeof(struct pipe_buffer), GFP_KERNEL); | |
| 1140 | + bufs = kcalloc(nr_pages, sizeof(*bufs), GFP_KERNEL | __GFP_NOWARN); | |
| 1141 | 1141 | if (unlikely(!bufs)) |
| 1142 | 1142 | return -ENOMEM; |
| 1143 | 1143 |