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| author | Anton Gusev <aagusev@ispras.ru> | 2023-02-03 16:22:13 +0300 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2023-02-03 16:52:10 +0300 |
| commit | 966d47e1f27c45507c5df82b2a2157e5a4fd3909 (patch) | |
| tree | b43fa4ec2c1693a7a2ea380503df9aebe8c23bc7 /drivers/firmware | |
| parent | 636ab417a7aec4ee993916e688eb5c5977570836 (diff) | |
| download | linux-966d47e1f27c45507c5df82b2a2157e5a4fd3909.tar.xz | |
efi: fix potential NULL deref in efi_mem_reserve_persistent
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>
Diffstat (limited to 'drivers/firmware')
| -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 a2b0cbc8741c..1e0b016fdc2b 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1007,6 +1007,8 @@ 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; |