| From e8814c811132a70f9b55418f7567378a34ad3883 Mon Sep 17 00:00:00 2001 |
| From: Darren Kenny <darren.kenny@oracle.com> |
| Date: Tue, 3 Nov 2020 16:43:37 +0000 |
| Subject: [PATCH] libgcrypt/mpi: Fix possible unintended sign extension |
| |
| The array of unsigned char gets promoted to a signed 32-bit int before |
| it is finally promoted to a size_t. There is the possibility that this |
| may result in the signed-bit being set for the intermediate signed |
| 32-bit int. We should ensure that the promotion is to the correct type |
| before we bitwise-OR the values. |
| |
| Fixes: CID 96697 |
| |
| Signed-off-by: Darren Kenny <darren.kenny@oracle.com> |
| Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> |
| Signed-off-by: Stefan SΓΈrensen <stefan.sorensen@spectralink.com> |
| --- |
| grub-core/lib/libgcrypt-grub/mpi/mpicoder.c | 2 +- |
| grub-core/lib/libgcrypt/mpi/mpicoder.c | 2 +- |
| 2 files changed, 2 insertions(+), 2 deletions(-) |
| |
| diff --git a/grub-core/lib/libgcrypt-grub/mpi/mpicoder.c b/grub-core/lib/libgcrypt-grub/mpi/mpicoder.c |
| index 3d55dfc..faf1cd6 100644 |
| --- a/grub-core/lib/libgcrypt-grub/mpi/mpicoder.c |
| +++ b/grub-core/lib/libgcrypt-grub/mpi/mpicoder.c |
| @@ -460,7 +460,7 @@ gcry_mpi_scan (struct gcry_mpi **ret_mpi, enum gcry_mpi_format format, |
| if (len && len < 4) |
| return gcry_error (GPG_ERR_TOO_SHORT); |
| |
| - n = (s[0] << 24 | s[1] << 16 | s[2] << 8 | s[3]); |
| + n = ((size_t)s[0] << 24 | (size_t)s[1] << 16 | (size_t)s[2] << 8 | (size_t)s[3]); |
| s += 4; |
| if (len) |
| len -= 4; |
| diff --git a/grub-core/lib/libgcrypt/mpi/mpicoder.c b/grub-core/lib/libgcrypt/mpi/mpicoder.c |
| index a3435ed..7ecad27 100644 |
| --- a/grub-core/lib/libgcrypt/mpi/mpicoder.c |
| +++ b/grub-core/lib/libgcrypt/mpi/mpicoder.c |
| @@ -458,7 +458,7 @@ gcry_mpi_scan (struct gcry_mpi **ret_mpi, enum gcry_mpi_format format, |
| if (len && len < 4) |
| return gcry_error (GPG_ERR_TOO_SHORT); |
| |
| - n = (s[0] << 24 | s[1] << 16 | s[2] << 8 | s[3]); |
| + n = ((size_t)s[0] << 24 | (size_t)s[1] << 16 | (size_t)s[2] << 8 | (size_t)s[3]); |
| s += 4; |
| if (len) |
| len -= 4; |
| -- |
| 2.14.2 |
| |