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| author | Lv Yunlong <lyl2019@mail.ustc.edu.cn> | 2021-03-10 00:31:27 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-24 11:54:18 +0100 |
| commit | 7168a2d61e5e6ee0160af272bdc1a54cd985d812 (patch) | |
| tree | 743fa07dd96844ea71d8c201bd097da6affab1eb | |
| parent | 46257a7630b25e974f5facee350c1ed4e3083157 (diff) | |
| download | linux-stable-7168a2d61e5e6ee0160af272bdc1a54cd985d812.tar.gz linux-stable-7168a2d61e5e6ee0160af272bdc1a54cd985d812.tar.bz2 linux-stable-7168a2d61e5e6ee0160af272bdc1a54cd985d812.zip | |
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 df3f9bcab581..4b7ee3fa9224 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -927,7 +927,7 @@ 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) { @@ -937,6 +937,7 @@ 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); } |