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| author | Lv Yunlong <lyl2019@mail.ustc.edu.cn> | 2021-03-10 11:31:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-24 13:26:45 +0300 |
| commit | b8ebe853abcac83428e80059bac22efbec28f5a2 (patch) | |
| tree | e687587c8f7cb52b5e3ec0fc8da8c8d8dba1b9b5 | |
| parent | 31e17169a1166b14ce9269497ffa0c0dd07a1387 (diff) | |
| download | linux-b8ebe853abcac83428e80059bac22efbec28f5a2.tar.xz | |
firmware/efi: Fix a use after bug in efi_mem_reserve_persistent
commit 9ceee7d0841a8f7d7644021ba7d4cc1fbc7966e3 upstream.
In the for loop in efi_mem_reserve_persistent(), prsv = rsv->next
use the unmapped rsv. Use the unmapped pages will cause segment
fault.
Fixes: 18df7577adae6 ("efi/memreserve: deal with memreserve entries in unmapped memory")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/firmware/efi/efi.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index b299e22b7532..3a2b60736915 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -1006,7 +1006,7 @@ 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; prsv = rsv->next) { + for (prsv = efi_memreserve_root->next; prsv; ) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { @@ -1016,6 +1016,7 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) memunmap(rsv); return efi_mem_reserve_iomem(addr, size); } + prsv = rsv->next; memunmap(rsv); } |