aboutsummaryrefslogtreecommitdiffstatshomepage
diff options
context:
space:
mode:
authorKees Cook <kees@kernel.org>2025-08-04 08:40:27 -0700
committerJoerg Roedel <joerg.roedel@amd.com>2025-08-15 11:50:47 +0200
commit8503d0fcb1086a7cfe26df67ca4bd9bd9e99bdec (patch)
treea06f03cebaf33b49cd80f97ac1eb683013898f41
parentLinux 6.17-rc1 (diff)
downloadwireguard-linux-8503d0fcb1086a7cfe26df67ca4bd9bd9e99bdec.tar.xz
wireguard-linux-8503d0fcb1086a7cfe26df67ca4bd9bd9e99bdec.zip
iommu/amd: Avoid stack buffer overflow from kernel cmdline
While the kernel command line is considered trusted in most environments, avoid writing 1 byte past the end of "acpiid" if the "str" argument is maximum length. Reported-by: Simcha Kosman <simcha.kosman@cyberark.com> Closes: https://lore.kernel.org/all/AS8P193MB2271C4B24BCEDA31830F37AE84A52@AS8P193MB2271.EURP193.PROD.OUTLOOK.COM Fixes: b6b26d86c61c ("iommu/amd: Add a length limitation for the ivrs_acpihid command-line parameter") Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: Ankit Soni <Ankit.Soni@amd.com> Link: https://lore.kernel.org/r/20250804154023.work.970-kees@kernel.org Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
-rw-r--r--drivers/iommu/amd/init.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 7b5af6176de9..8de689b2c5ed 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -3638,7 +3638,7 @@ static int __init parse_ivrs_acpihid(char *str)
{
u32 seg = 0, bus, dev, fn;
char *hid, *uid, *p, *addr;
- char acpiid[ACPIID_LEN] = {0};
+ char acpiid[ACPIID_LEN + 1] = { }; /* size with NULL terminator */
int i;
addr = strchr(str, '@');
@@ -3664,7 +3664,7 @@ static int __init parse_ivrs_acpihid(char *str)
/* We have the '@', make it the terminator to get just the acpiid */
*addr++ = 0;
- if (strlen(str) > ACPIID_LEN + 1)
+ if (strlen(str) > ACPIID_LEN)
goto not_found;
if (sscanf(str, "=%s", acpiid) != 1)