commit
3ff84a7f36554b257cd57325b1a7c1fa4b49fbe3 upstream.
This reverts commit
5c5e3b33b7cb959a401f823707bee006caadd76e.
The commit breaks ARM thusly:
| Mount-cache hash table entries: 512
| slab error in verify_redzone_free(): cache `idr_layer_cache': memory outside object was overwritten
| Backtrace:
| [<
c0227088>] (dump_backtrace+0x0/0x110) from [<
c0431afc>] (dump_stack+0x18/0x1c)
| [<
c0431ae4>] (dump_stack+0x0/0x1c) from [<
c0293304>] (__slab_error+0x28/0x30)
| [<
c02932dc>] (__slab_error+0x0/0x30) from [<
c0293a74>] (cache_free_debugcheck+0x1c0/0x2b8)
| [<
c02938b4>] (cache_free_debugcheck+0x0/0x2b8) from [<
c0293f78>] (kmem_cache_free+0x3c/0xc0)
| [<
c0293f3c>] (kmem_cache_free+0x0/0xc0) from [<
c032b1c8>] (ida_get_new_above+0x19c/0x1c0)
| [<
c032b02c>] (ida_get_new_above+0x0/0x1c0) from [<
c02af7ec>] (alloc_vfsmnt+0x54/0x144)
| [<
c02af798>] (alloc_vfsmnt+0x0/0x144) from [<
c0299830>] (vfs_kern_mount+0x30/0xec)
| [<
c0299800>] (vfs_kern_mount+0x0/0xec) from [<
c0299908>] (kern_mount_data+0x1c/0x20)
| [<
c02998ec>] (kern_mount_data+0x0/0x20) from [<
c02146c4>] (sysfs_init+0x68/0xc8)
| [<
c021465c>] (sysfs_init+0x0/0xc8) from [<
c02137d4>] (mnt_init+0x90/0x1b0)
| [<
c0213744>] (mnt_init+0x0/0x1b0) from [<
c0213388>] (vfs_caches_init+0x100/0x140)
| [<
c0213288>] (vfs_caches_init+0x0/0x140) from [<
c0208c0c>] (start_kernel+0x2e8/0x368)
| [<
c0208924>] (start_kernel+0x0/0x368) from [<
c0208034>] (__enable_mmu+0x0/0x2c)
|
c0113268: redzone 1:0xd84156c5c032b3ac, redzone 2:0xd84156c5635688c0.
| slab error in cache_alloc_debugcheck_after(): cache `idr_layer_cache': double free, or memory outside object was overwritten
| ...
|
c011307c: redzone 1:0x9f91102ffffffff, redzone 2:0x9f911029d74e35b
| slab: Internal list corruption detected in cache 'idr_layer_cache'(24), slabp
c0113000(16). Hexdump:
|
| 000: 20 4f 10 c0 20 4f 10 c0 7c 00 00 00 7c 30 11 c0
| 010: 10 00 00 00 10 00 00 00 00 00 c9 17 fe ff ff ff
| 020: fe ff ff ff fe ff ff ff fe ff ff ff fe ff ff ff
| 030: fe ff ff ff fe ff ff ff fe ff ff ff fe ff ff ff
| 040: fe ff ff ff fe ff ff ff fe ff ff ff fe ff ff ff
| 050: fe ff ff ff fe ff ff ff fe ff ff ff 11 00 00 00
| 060: 12 00 00 00 13 00 00 00 14 00 00 00 15 00 00 00
| 070: 16 00 00 00 17 00 00 00 c0 88 56 63
| kernel BUG at /home/rmk/git/linux-2.6-rmk/mm/slab.c:2928!
Reference: https://lkml.org/lkml/2011/2/7/238
Reported-and-analyzed-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
if (ralign < align) {
ralign = align;
}
- /* disable debug if not aligning with REDZONE_ALIGN */
- if (ralign & (__alignof__(unsigned long long) - 1))
+ /* disable debug if necessary */
+ if (ralign > __alignof__(unsigned long long))
flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
/*
* 4) Store it.
*/
if (flags & SLAB_RED_ZONE) {
/* add space for red zone words */
- cachep->obj_offset += align;
- size += align + sizeof(unsigned long long);
+ cachep->obj_offset += sizeof(unsigned long long);
+ size += 2 * sizeof(unsigned long long);
}
if (flags & SLAB_STORE_USER) {
/* user store requires one word storage behind the end of