https://github.com/torvalds/linux
Revision 140456f994195b568ecd7fc2287a34eadffef3ca authored by Andrey Ryabinin on 17 February 2021, 14:30:04 UTC, committed by Joerg Roedel on 04 March 2021, 12:15:56 UTC
increase_address_space() calls get_zeroed_page(gfp) under spin_lock with disabled interrupts. gfp flags passed to increase_address_space() may allow sleeping, so it comes to this: BUG: sleeping function called from invalid context at mm/page_alloc.c:4342 in_atomic(): 1, irqs_disabled(): 1, pid: 21555, name: epdcbbf1qnhbsd8 Call Trace: dump_stack+0x66/0x8b ___might_sleep+0xec/0x110 __alloc_pages_nodemask+0x104/0x300 get_zeroed_page+0x15/0x40 iommu_map_page+0xdd/0x3e0 amd_iommu_map+0x50/0x70 iommu_map+0x106/0x220 vfio_iommu_type1_ioctl+0x76e/0x950 [vfio_iommu_type1] do_vfs_ioctl+0xa3/0x6f0 ksys_ioctl+0x66/0x70 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x4e/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fix this by moving get_zeroed_page() out of spin_lock/unlock section. Fixes: 754265bcab ("iommu/amd: Fix race in increase_address_space()") Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com> Acked-by: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20210217143004.19165-1-arbn@yandex-team.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
1 parent 45e606f
Tip revision: 140456f994195b568ecd7fc2287a34eadffef3ca authored by Andrey Ryabinin on 17 February 2021, 14:30:04 UTC
iommu/amd: Fix sleeping in atomic in increase_address_space()
iommu/amd: Fix sleeping in atomic in increase_address_space()
Tip revision: 140456f
dh_helper.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2016, Intel Corporation
* Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/string.h>
#include <crypto/dh.h>
#include <crypto/kpp.h>
#define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 4 * sizeof(int))
static inline u8 *dh_pack_data(u8 *dst, u8 *end, const void *src, size_t size)
{
if (!dst || size > end - dst)
return NULL;
memcpy(dst, src, size);
return dst + size;
}
static inline const u8 *dh_unpack_data(void *dst, const void *src, size_t size)
{
memcpy(dst, src, size);
return src + size;
}
static inline unsigned int dh_data_size(const struct dh *p)
{
return p->key_size + p->p_size + p->q_size + p->g_size;
}
unsigned int crypto_dh_key_len(const struct dh *p)
{
return DH_KPP_SECRET_MIN_SIZE + dh_data_size(p);
}
EXPORT_SYMBOL_GPL(crypto_dh_key_len);
int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params)
{
u8 *ptr = buf;
u8 * const end = ptr + len;
struct kpp_secret secret = {
.type = CRYPTO_KPP_SECRET_TYPE_DH,
.len = len
};
if (unlikely(!len))
return -EINVAL;
ptr = dh_pack_data(ptr, end, &secret, sizeof(secret));
ptr = dh_pack_data(ptr, end, ¶ms->key_size,
sizeof(params->key_size));
ptr = dh_pack_data(ptr, end, ¶ms->p_size, sizeof(params->p_size));
ptr = dh_pack_data(ptr, end, ¶ms->q_size, sizeof(params->q_size));
ptr = dh_pack_data(ptr, end, ¶ms->g_size, sizeof(params->g_size));
ptr = dh_pack_data(ptr, end, params->key, params->key_size);
ptr = dh_pack_data(ptr, end, params->p, params->p_size);
ptr = dh_pack_data(ptr, end, params->q, params->q_size);
ptr = dh_pack_data(ptr, end, params->g, params->g_size);
if (ptr != end)
return -EINVAL;
return 0;
}
EXPORT_SYMBOL_GPL(crypto_dh_encode_key);
int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params)
{
const u8 *ptr = buf;
struct kpp_secret secret;
if (unlikely(!buf || len < DH_KPP_SECRET_MIN_SIZE))
return -EINVAL;
ptr = dh_unpack_data(&secret, ptr, sizeof(secret));
if (secret.type != CRYPTO_KPP_SECRET_TYPE_DH)
return -EINVAL;
ptr = dh_unpack_data(¶ms->key_size, ptr, sizeof(params->key_size));
ptr = dh_unpack_data(¶ms->p_size, ptr, sizeof(params->p_size));
ptr = dh_unpack_data(¶ms->q_size, ptr, sizeof(params->q_size));
ptr = dh_unpack_data(¶ms->g_size, ptr, sizeof(params->g_size));
if (secret.len != crypto_dh_key_len(params))
return -EINVAL;
/*
* Don't permit the buffer for 'key' or 'g' to be larger than 'p', since
* some drivers assume otherwise.
*/
if (params->key_size > params->p_size ||
params->g_size > params->p_size || params->q_size > params->p_size)
return -EINVAL;
/* Don't allocate memory. Set pointers to data within
* the given buffer
*/
params->key = (void *)ptr;
params->p = (void *)(ptr + params->key_size);
params->q = (void *)(ptr + params->key_size + params->p_size);
params->g = (void *)(ptr + params->key_size + params->p_size +
params->q_size);
/*
* Don't permit 'p' to be 0. It's not a prime number, and it's subject
* to corner cases such as 'mod 0' being undefined or
* crypto_kpp_maxsize() returning 0.
*/
if (memchr_inv(params->p, 0, params->p_size) == NULL)
return -EINVAL;
/* It is permissible to not provide Q. */
if (params->q_size == 0)
params->q = NULL;
return 0;
}
EXPORT_SYMBOL_GPL(crypto_dh_decode_key);
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