Reviewed-by: Star Zeng <[email protected]> -----Original Message----- From: Wang, Jian J Sent: Monday, October 29, 2018 4:22 PM To: [email protected] Cc: Wu, Hao A <[email protected]>; Zeng, Star <[email protected]> Subject: [PATCH] MdeModulePkg/Core: fix an issue of potential NULL pointer access
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1286 This issue is introduced by bb685071c2602cf786ea84c69bbebf2158194a38. The *MemorySpaceMap assigned with NULL (line 1710) value might be accessed (line 1726/1730) without any sanity check. Although it won't happen in practice because of line 1722, we still need to add check against NULL to make static code analyzer happy. 1710 *MemorySpaceMap = NULL; .... ... 1722 if (DescriptorCount == *NumberOfDescriptors) { .... ... 1726 Descriptor = *MemorySpaceMap; .... ... 1730 BuildMemoryDescriptor (Descriptor, Entry); Tests: Pass build and boot to shell. Cc: Hao Wu <[email protected]> Cc: Star Zeng <[email protected]> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Jian J Wang <[email protected]> --- MdeModulePkg/Core/Dxe/Gcd/Gcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/MdeModulePkg/Core/Dxe/Gcd/Gcd.c b/MdeModulePkg/Core/Dxe/Gcd/Gcd.c index 8bbdf7129f..a76d2db73c 100644 --- a/MdeModulePkg/Core/Dxe/Gcd/Gcd.c +++ b/MdeModulePkg/Core/Dxe/Gcd/Gcd.c @@ -1719,7 +1719,7 @@ CoreGetMemorySpaceMap ( // AllocatePool() called below has to be running outside the GCD lock. // DescriptorCount = CoreCountGcdMapEntry (&mGcdMemorySpaceMap); - if (DescriptorCount == *NumberOfDescriptors) { + if (DescriptorCount == *NumberOfDescriptors && *MemorySpaceMap != + NULL) { // // Fill in the MemorySpaceMap if no memory space map change. // -- 2.16.2.windows.1 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
