diff options
| author | Anton Gusev <aagusev@ispras.ru> | 2023-02-03 16:22:13 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-22 12:50:25 +0100 |
| commit | d92a25627bcdf264183670da73c9a60c0bac327e (patch) | |
| tree | fa0a62c39fa69bca136b7a14fce2c83a19fd10b5 /drivers/firmware/efi | |
| parent | ed6c5e8caf55778500202775167e8ccdb1a030cb (diff) | |
efi: fix potential NULL deref in efi_mem_reserve_persistent
[ Upstream commit 966d47e1f27c45507c5df82b2a2157e5a4fd3909 ]
When iterating on a linked list, a result of memremap is dereferenced
without checking it for NULL.
This patch adds a check that falls back on allocating a new page in
case memremap doesn't succeed.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 18df7577adae ("efi/memreserve: deal with memreserve entries in unmapped memory")
Signed-off-by: Anton Gusev <aagusev@ispras.ru>
[ardb: return -ENOMEM instead of breaking out of the loop]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/firmware/efi')
| -rw-r--r-- | drivers/firmware/efi/efi.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index eb98018ab420..ed31b08855f9 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1022,6 +1022,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) /* first try to find a slot in an existing linked list entry */ for (prsv = efi_memreserve_root->next; prsv; ) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); + if (!rsv) + return -ENOMEM; index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { rsv->entry[index].base = addr; |