diff options
Diffstat (limited to 'debian/patches/0091-fs-btrfs-Fix-more-ASAN-and-SEGV-issues-found-with-fu.patch')
| -rw-r--r-- | debian/patches/0091-fs-btrfs-Fix-more-ASAN-and-SEGV-issues-found-with-fu.patch | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/debian/patches/0091-fs-btrfs-Fix-more-ASAN-and-SEGV-issues-found-with-fu.patch b/debian/patches/0091-fs-btrfs-Fix-more-ASAN-and-SEGV-issues-found-with-fu.patch new file mode 100644 index 0000000..4ae22c9 --- /dev/null +++ b/debian/patches/0091-fs-btrfs-Fix-more-ASAN-and-SEGV-issues-found-with-fu.patch @@ -0,0 +1,133 @@ +From 22976cf1b9864455173e1bfc617bc63f13fbecf7 Mon Sep 17 00:00:00 2001 +From: Darren Kenny <darren.kenny@oracle.com> +Date: Tue, 29 Mar 2022 15:52:46 +0000 +Subject: fs/btrfs: Fix more ASAN and SEGV issues found with fuzzing + +The fuzzer is generating btrfs file systems that have chunks with +invalid combinations of stripes and substripes for the given RAID +configurations. + +After examining the Linux kernel fs/btrfs/tree-checker.c code, it +appears that sub-stripes should only be applied to RAID10, and in that +case there should only ever be 2 of them. + +Similarly, RAID single should only have 1 stripe, and RAID1/1C3/1C4 +should have 2. 3 or 4 stripes respectively, which is what redundancy +corresponds. + +Some of the chunks ended up with a size of 0, which grub_malloc() still +returned memory for and in turn generated ASAN errors later when +accessed. + +While it would be possible to specifically limit the number of stripes, +a more correct test was on the combination of the chunk item, and the +number of stripes by the size of the chunk stripe structure in +comparison to the size of the chunk itself. + +Signed-off-by: Darren Kenny <darren.kenny@oracle.com> +Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> +--- + grub-core/fs/btrfs.c | 55 ++++++++++++++++++++++++++++++++++++++++++++ + 1 file changed, 55 insertions(+) + +diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c +index eb9857d74..b3d71cd9e 100644 +--- a/grub-core/fs/btrfs.c ++++ b/grub-core/fs/btrfs.c +@@ -912,6 +912,12 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + return grub_error (GRUB_ERR_BAD_FS, + "couldn't find the chunk descriptor"); + ++ if (!chsize) ++ { ++ grub_dprintf ("btrfs", "zero-size chunk\n"); ++ return grub_error (GRUB_ERR_BAD_FS, ++ "got an invalid zero-size chunk"); ++ } + chunk = grub_malloc (chsize); + if (!chunk) + return grub_errno; +@@ -970,6 +976,16 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + stripe_length = grub_divmod64 (grub_le_to_cpu64 (chunk->size), + nstripes, + NULL); ++ ++ /* For single, there should be exactly 1 stripe. */ ++ if (grub_le_to_cpu16 (chunk->nstripes) != 1) ++ { ++ grub_dprintf ("btrfs", "invalid RAID_SINGLE: nstripes != 1 (%u)\n", ++ grub_le_to_cpu16 (chunk->nstripes)); ++ return grub_error (GRUB_ERR_BAD_FS, ++ "invalid RAID_SINGLE: nstripes != 1 (%u)", ++ grub_le_to_cpu16 (chunk->nstripes)); ++ } + if (stripe_length == 0) + stripe_length = 512; + stripen = grub_divmod64 (off, stripe_length, &stripe_offset); +@@ -989,6 +1005,19 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + stripen = 0; + stripe_offset = off; + csize = grub_le_to_cpu64 (chunk->size) - off; ++ ++ /* ++ * Redundancy, and substripes only apply to RAID10, and there ++ * should be exactly 2 sub-stripes. ++ */ ++ if (grub_le_to_cpu16 (chunk->nstripes) != redundancy) ++ { ++ grub_dprintf ("btrfs", "invalid RAID1: nstripes != %u (%u)\n", ++ redundancy, grub_le_to_cpu16 (chunk->nstripes)); ++ return grub_error (GRUB_ERR_BAD_FS, ++ "invalid RAID1: nstripes != %u (%u)", ++ redundancy, grub_le_to_cpu16 (chunk->nstripes)); ++ } + break; + } + case GRUB_BTRFS_CHUNK_TYPE_RAID0: +@@ -1025,6 +1054,20 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + stripe_offset = low + chunk_stripe_length + * high; + csize = chunk_stripe_length - low; ++ ++ /* ++ * Substripes only apply to RAID10, and there ++ * should be exactly 2 sub-stripes. ++ */ ++ if (grub_le_to_cpu16 (chunk->nsubstripes) != 2) ++ { ++ grub_dprintf ("btrfs", "invalid RAID10: nsubstripes != 2 (%u)", ++ grub_le_to_cpu16 (chunk->nsubstripes)); ++ return grub_error (GRUB_ERR_BAD_FS, ++ "invalid RAID10: nsubstripes != 2 (%u)", ++ grub_le_to_cpu16 (chunk->nsubstripes)); ++ } ++ + break; + } + case GRUB_BTRFS_CHUNK_TYPE_RAID5: +@@ -1124,6 +1167,8 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + + for (j = 0; j < 2; j++) + { ++ grub_size_t est_chunk_alloc = 0; ++ + grub_dprintf ("btrfs", "chunk 0x%" PRIxGRUB_UINT64_T + "+0x%" PRIxGRUB_UINT64_T + " (%d stripes (%d substripes) of %" +@@ -1136,6 +1181,16 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr, + grub_dprintf ("btrfs", "reading laddr 0x%" PRIxGRUB_UINT64_T "\n", + addr); + ++ if (grub_mul (sizeof (struct grub_btrfs_chunk_stripe), ++ grub_le_to_cpu16 (chunk->nstripes), &est_chunk_alloc) || ++ grub_add (est_chunk_alloc, ++ sizeof (struct grub_btrfs_chunk_item), &est_chunk_alloc) || ++ est_chunk_alloc > chunk->size) ++ { ++ err = GRUB_ERR_BAD_FS; ++ break; ++ } ++ + if (is_raid56) + { + err = btrfs_read_from_chunk (data, chunk, stripen, |