summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorNikita Zhandarovich <n.zhandarovich@fintech.ru>2023-03-06 08:06:56 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-03-22 13:27:12 +0100
commitffdf8d81c48822a329af9f31dc239090f4a60761 (patch)
treeae3a780695c6e45c90394b5e07b1b3504a5c1385
parente6d5a0a1e6820f7a7c47f757240b25b43f884eff (diff)
downloadexynos-ffdf8d81c48822a329af9f31dc239090f4a60761.tar.gz
x86/mm: Fix use of uninitialized buffer in sme_enable()
commit cbebd68f59f03633469f3ecf9bea99cd6cce3854 upstream. cmdline_find_option() may fail before doing any initialization of the buffer array. This may lead to unpredictable results when the same buffer is used later in calls to strncmp() function. Fix the issue by returning early if cmdline_find_option() returns an error. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE. Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption") Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/20230306160656.14844-1-n.zhandarovich@fintech.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/mm/mem_encrypt_identity.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c
index 650d5a6cafc7..832c899b7b73 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c
@@ -563,7 +563,8 @@ void __init sme_enable(struct boot_params *bp)
cmdline_ptr = (const char *)((u64)bp->hdr.cmd_line_ptr |
((u64)bp->ext_cmd_line_ptr << 32));
- cmdline_find_option(cmdline_ptr, cmdline_arg, buffer, sizeof(buffer));
+ if (cmdline_find_option(cmdline_ptr, cmdline_arg, buffer, sizeof(buffer)) < 0)
+ return;
if (!strncmp(buffer, cmdline_on, sizeof(buffer)))
sme_me_mask = me_mask;