diff options
| author | Kees Cook <kees@kernel.org> | 2025-08-04 08:40:27 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-28 16:31:13 +0200 |
| commit | 4bdb0f78bddbfa77d3ab458a21dd9cec495d317a (patch) | |
| tree | a84b39cc3724e47b176d415365cd8d53f0b2a953 | |
| parent | f1424c830d6ce840341aac33fe99c8ac45447ac1 (diff) | |
iommu/amd: Avoid stack buffer overflow from kernel cmdline
[ Upstream commit 8503d0fcb1086a7cfe26df67ca4bd9bd9e99bdec ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/iommu/amd/init.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index ff11cd7e5c06..f5b544e0f230 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -3598,7 +3598,7 @@ 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, '@'); @@ -3624,7 +3624,7 @@ 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) |