Commit e85c21ba authored by Ze Zuo's avatar Ze Zuo
Browse files

mm/mempolicy.c: fix the out-of-bounds access issue in mpol_parse_str 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9S5SX


CVE: NA

------------------------------------------------------------------

commit 50afa875("mm: prepare to support weighted interleaving mempolicy")
kabi reservation for structures task_struct, vm_operations_struct, for
support of weighted L/R-based memory interleaving Allocation, the above
patch failed to add MPOL_WEIGHTED_INTERLEAVE to the policy_modes array,
resulting in out-of-bounds accesses when accessing the policy_modes array
in mpol_parse_str.

Fixes: 50afa875 ("mm: prepare to support weighted interleaving mempolicy")
Signed-off-by: default avatarZe Zuo <zuoze1@huawei.com>
parent bc160a82

mm/mempolicy.c

+3 −1
Original line number Diff line number Diff line
@@ -1477,7 +1477,8 @@ static inline int sanitize_mpol_flags(int *mode, unsigned short *flags) 
	*flags = *mode & MPOL_MODE_FLAGS;

	*mode &= ~MPOL_MODE_FLAGS;



	if ((unsigned int)(*mode) >=  MPOL_MAX)

	if ((unsigned int)(*mode) >=  MPOL_MAX ||

	    (unsigned int)(*mode) == MPOL_WEIGHTED_INTERLEAVE)

		return -EINVAL;

	if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES))

		return -EINVAL;
@@ -2989,6 +2990,7 @@ static const char * const policy_modes[] = 
	[MPOL_PREFERRED]  = "prefer",

	[MPOL_BIND]       = "bind",

	[MPOL_INTERLEAVE] = "interleave",

	[MPOL_WEIGHTED_INTERLEAVE] = "weighted interleave",

	[MPOL_LOCAL]      = "local",

	[MPOL_PREFERRED_MANY]  = "prefer (many)",

};