From: Pavel Paklov <Pavel.Paklov@cyberprotect.ru> stable inclusion from stable-v6.6.90 commit 13d67528e1ae4486e9ab24b70122fab104c73c29 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IC991Z CVE: CVE-2025-37927 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 8dee308e4c01dea48fc104d37f92d5b58c50b96c upstream. There is a string parsing logic error which can lead to an overflow of hid or uid buffers. Comparing ACPIID_LEN against a total string length doesn't take into account the lengths of individual hid and uid buffers so the check is insufficient in some cases. For example if the length of hid string is 4 and the length of the uid string is 260, the length of str will be equal to ACPIID_LEN + 1 but uid string will overflow uid buffer which size is 256. The same applies to the hid string with length 13 and uid string with length 250. Check the length of hid and uid strings separately to prevent buffer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: ca3bf5d47cec ("iommu/amd: Introduces ivrs_acpihid kernel parameter") Cc: stable@vger.kernel.org Signed-off-by: Pavel Paklov <Pavel.Paklov@cyberprotect.ru> Link: https://lore.kernel.org/r/20250325092259.392844-1-Pavel.Paklov@cyberprotect.... Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jiacheng Yu <yujiacheng3@huawei.com> --- drivers/iommu/amd/init.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 4beddd8cc420..e3d4a23b66fd 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -3690,6 +3690,14 @@ static int __init parse_ivrs_acpihid(char *str) while (*uid == '0' && *(uid + 1)) uid++; + if (strlen(hid) >= ACPIHID_HID_LEN) { + pr_err("Invalid command line: hid is too long\n"); + return 1; + } else if (strlen(uid) >= ACPIHID_UID_LEN) { + pr_err("Invalid command line: uid is too long\n"); + return 1; + } + i = early_acpihid_map_size++; memcpy(early_acpihid_map[i].hid, hid, strlen(hid)); memcpy(early_acpihid_map[i].uid, uid, strlen(uid)); -- 2.43.0