diff --git a/SOURCES/0677-fs-ext2-Rework-out-of-bounds-read-for-inline-and-ext.patch b/SOURCES/0677-fs-ext2-Rework-out-of-bounds-read-for-inline-and-ext.patch new file mode 100644 index 0000000..162ee8f --- /dev/null +++ b/SOURCES/0677-fs-ext2-Rework-out-of-bounds-read-for-inline-and-ext.patch @@ -0,0 +1,65 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Michael Chang +Date: Fri, 21 Feb 2025 09:06:12 +0800 +Subject: [PATCH] fs/ext2: Rework out-of-bounds read for inline and external + extents + +Previously, the number of extent entries was not properly capped based +on the actual available space. This could lead to insufficient reads for +external extents since the computation was based solely on the inline +extent layout. + +In this patch, when processing the extent header we determine whether +the header is stored inline, i.e. at inode->blocks.dir_blocks, or in an +external extent block. We then clamp the number of entries accordingly +(using max_inline_ext for inline extents and max_external_ext for +external extent blocks). + +This change ensures that only the valid number of extent entries is +processed preventing out-of-bound reads and potential filesystem +corruption. + +Fixes: 7e2f750f0a (fs/ext2: Fix out-of-bounds read for inline extents) + +Signed-off-by: Michael Chang +Tested-by: Christian Hesse +Reviewed-by: Daniel Kiper +--- + grub-core/fs/ext2.c | 15 ++++++++++++++- + 1 file changed, 14 insertions(+), 1 deletion(-) + +diff --git a/grub-core/fs/ext2.c b/grub-core/fs/ext2.c +index dc62a6c..b144549 100644 +--- a/grub-core/fs/ext2.c ++++ b/grub-core/fs/ext2.c +@@ -474,7 +474,10 @@ grub_ext2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock) + int i; + grub_disk_addr_t ret; + grub_uint16_t nent; ++ /* Maximum number of extent entries in the inode's inline extent area. */ + const grub_uint16_t max_inline_ext = sizeof (inode->blocks) / sizeof (*ext) - 1; /* Minus 1 extent header. */ ++ /* Maximum number of extent entries in the external extent block. */ ++ const grub_uint16_t max_external_ext = EXT2_BLOCK_SIZE (data) / sizeof (*ext) - 1; /* Minus 1 extent header. */ + + leaf = grub_ext4_find_leaf (data, (struct grub_ext4_extent_header *) inode->blocks.dir_blocks, fileblock); + if (! leaf) +@@ -487,8 +490,18 @@ grub_ext2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock) + + nent = grub_le_to_cpu16 (leaf->entries); + +- if (leaf->depth == 0) ++ /* ++ * Determine the effective number of extent entries (nent) to process. ++ * If the extent header (leaf) is stored inline in the inode’s block ++ * area, i.e. at inode->blocks.dir_blocks, then only max_inline_ext ++ * entries can fit. Otherwise, if the header was read from an external ++ * extent block use the larger limit, max_external_ext, based on the ++ * full block size. ++ */ ++ if (leaf == (struct grub_ext4_extent_header *) inode->blocks.dir_blocks) + nent = grub_min (nent, max_inline_ext); ++ else ++ nent = grub_min (nent, max_external_ext); + + for (i = 0; i < nent; i++) + { diff --git a/SOURCES/grub.patches b/SOURCES/grub.patches index 36e2c06..a913b39 100644 --- a/SOURCES/grub.patches +++ b/SOURCES/grub.patches @@ -673,3 +673,4 @@ Patch0673: 0673-fs-xfs-Fix-XFS-directory-extent-parsing.patch Patch0674: 0674-fs-xfs-Add-large-extent-counters-incompat-feature-su.patch Patch0675: 0675-fs-xfs-Handle-non-continuous-data-blocks-in-director.patch Patch0676: 0676-fs-xfs-fix-large-extent-counters-incompat-feature-su.patch +Patch0677: 0677-fs-ext2-Rework-out-of-bounds-read-for-inline-and-ext.patch diff --git a/SPECS/grub2.spec b/SPECS/grub2.spec index 0db72cf..112d5c1 100644 --- a/SPECS/grub2.spec +++ b/SPECS/grub2.spec @@ -7,7 +7,7 @@ Name: grub2 Epoch: 1 Version: 2.02 -Release: 164%{?dist} +Release: 165%{?dist} Summary: Bootloader with support for Linux, Multiboot and more Group: System Environment/Base License: GPLv3+ @@ -523,6 +523,10 @@ fi %endif %changelog +* Thu Apr 17 2025 Nicolas Frayer - 2.02-165 +- fs/ext2: Rework of OOB read patch +- Resolves: #RHEL-86553 + * Fri Apr 4 2025 Leo Sandoval - 2.02-164 - Bump NVR to sign the build - Resolves: #RHEL-85627