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[PATCH openEuler-1.0-LTS] ext4: fix corruption during on-line resize
by Zhihao Cheng 21 May '24

21 May '24

From: Maximilian Heyne <mheyne(a)amazon.de> stable inclusion from stable-v5.10.215 commit e8e8b197317228b5089ed9e7802dadf3ccaa027a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CF CVE: CVE-2024-35807 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit a6b3bfe176e8a5b05ec4447404e412c2a3fc92cc ] We observed a corruption during on-line resize of a file system that is larger than 16 TiB with 4k block size. With having more then 2^32 blocks resize_inode is turned off by default by mke2fs. The issue can be reproduced on a smaller file system for convenience by explicitly turning off resize_inode. An on-line resize across an 8 GiB boundary (the size of a meta block group in this setup) then leads to a corruption: dev=/dev/<some_dev> # should be >= 16 GiB mkdir -p /corruption /sbin/mke2fs -t ext4 -b 4096 -O ^resize_inode $dev $((2 * 2**21 - 2**15)) mount -t ext4 $dev /corruption dd if=/dev/zero bs=4096 of=/corruption/test count=$((2*2**21 - 4*2**15)) sha1sum /corruption/test # 79d2658b39dcfd77274e435b0934028adafaab11 /corruption/test /sbin/resize2fs $dev $((2*2**21)) # drop page cache to force reload the block from disk echo 1 > /proc/sys/vm/drop_caches sha1sum /corruption/test # 3c2abc63cbf1a94c9e6977e0fbd72cd832c4d5c3 /corruption/test 2^21 = 2^15*2^6 equals 8 GiB whereof 2^15 is the number of blocks per block group and 2^6 are the number of block groups that make a meta block group. The last checksum might be different depending on how the file is laid out across the physical blocks. The actual corruption occurs at physical block 63*2^15 = 2064384 which would be the location of the backup of the meta block group's block descriptor. During the on-line resize the file system will be converted to meta_bg starting at s_first_meta_bg which is 2 in the example - meaning all block groups after 16 GiB. However, in ext4_flex_group_add we might add block groups that are not part of the first meta block group yet. In the reproducer we achieved this by substracting the size of a whole block group from the point where the meta block group would start. This must be considered when updating the backup block group descriptors to follow the non-meta_bg layout. The fix is to add a test whether the group to add is already part of the meta block group or not. Fixes: 01f795f9e0d67 ("ext4: add online resizing support for meta_bg and 64-bit file systems") Cc: <stable(a)vger.kernel.org> Signed-off-by: Maximilian Heyne <mheyne(a)amazon.de> Tested-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Reviewed-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Link: https://lore.kernel.org/r/20240215155009.94493-1-mheyne@amazon.de Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: fs/ext4/resize.c [ Commit 31f13421c004a420c("ext4: correct offset of gdb backup in non meta_bg group to update_backups") is not applied. ] Signed-off-by: Zhihao Cheng <chengzhihao(a)huaweicloud.com> --- fs/ext4/resize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 767cbebf04ee..eb10a43b1498 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1558,7 +1558,8 @@ static int ext4_flex_group_add(struct super_block *sb, int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); - int meta_bg = ext4_has_feature_meta_bg(sb); + int meta_bg = ext4_has_feature_meta_bg(sb) && + gdb_num >= le32_to_cpu(es->s_first_meta_bg); sector_t old_gdb = 0; update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, -- 2.31.1

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[PATCH openEuler-22.03-LTS-SP2 0/2] CVE-2023-52676
by Pu Lehui 21 May '24

21 May '24

Andrei Matei (2): bpf: Fix verification of indirect var-off stack access bpf: Guard stack limits against 32bit overflow kernel/bpf/verifier.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) -- 2.34.1

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[PATCH openEuler-22.03-LTS-SP1 0/2] CVE-2023-52676
by Pu Lehui 21 May '24

21 May '24

Andrei Matei (2): bpf: Fix verification of indirect var-off stack access bpf: Guard stack limits against 32bit overflow kernel/bpf/verifier.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) -- 2.34.1

2 3

[PATCH openEuler-22.03-LTS 0/2] CVE-2023-52676
by Pu Lehui 21 May '24

21 May '24

Andrei Matei (2): bpf: Fix verification of indirect var-off stack access bpf: Guard stack limits against 32bit overflow kernel/bpf/verifier.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) -- 2.34.1

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[PATCH openEuler-1.0-LTS 0/1] CVE-2023-52669
by Yongqiang Liu 21 May '24

21 May '24

Herbert Xu (1): crypto: s390/aes - Fix buffer overread in CTR mode arch/s390/crypto/aes_s390.c | 5 +++-- arch/s390/crypto/paes_s390.c | 4 +++- 2 files changed, 6 insertions(+), 3 deletions(-) -- 2.34.1

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[PATCH openEuler-22.03-LTS-SP2] ext4: fix corruption during on-line resize
by Zhihao Cheng 21 May '24

21 May '24

From: Maximilian Heyne <mheyne(a)amazon.de> stable inclusion from stable-v5.10.215 commit e8e8b197317228b5089ed9e7802dadf3ccaa027a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CF CVE: CVE-2024-35807 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit a6b3bfe176e8a5b05ec4447404e412c2a3fc92cc ] We observed a corruption during on-line resize of a file system that is larger than 16 TiB with 4k block size. With having more then 2^32 blocks resize_inode is turned off by default by mke2fs. The issue can be reproduced on a smaller file system for convenience by explicitly turning off resize_inode. An on-line resize across an 8 GiB boundary (the size of a meta block group in this setup) then leads to a corruption: dev=/dev/<some_dev> # should be >= 16 GiB mkdir -p /corruption /sbin/mke2fs -t ext4 -b 4096 -O ^resize_inode $dev $((2 * 2**21 - 2**15)) mount -t ext4 $dev /corruption dd if=/dev/zero bs=4096 of=/corruption/test count=$((2*2**21 - 4*2**15)) sha1sum /corruption/test # 79d2658b39dcfd77274e435b0934028adafaab11 /corruption/test /sbin/resize2fs $dev $((2*2**21)) # drop page cache to force reload the block from disk echo 1 > /proc/sys/vm/drop_caches sha1sum /corruption/test # 3c2abc63cbf1a94c9e6977e0fbd72cd832c4d5c3 /corruption/test 2^21 = 2^15*2^6 equals 8 GiB whereof 2^15 is the number of blocks per block group and 2^6 are the number of block groups that make a meta block group. The last checksum might be different depending on how the file is laid out across the physical blocks. The actual corruption occurs at physical block 63*2^15 = 2064384 which would be the location of the backup of the meta block group's block descriptor. During the on-line resize the file system will be converted to meta_bg starting at s_first_meta_bg which is 2 in the example - meaning all block groups after 16 GiB. However, in ext4_flex_group_add we might add block groups that are not part of the first meta block group yet. In the reproducer we achieved this by substracting the size of a whole block group from the point where the meta block group would start. This must be considered when updating the backup block group descriptors to follow the non-meta_bg layout. The fix is to add a test whether the group to add is already part of the meta block group or not. Fixes: 01f795f9e0d67 ("ext4: add online resizing support for meta_bg and 64-bit file systems") Cc: <stable(a)vger.kernel.org> Signed-off-by: Maximilian Heyne <mheyne(a)amazon.de> Tested-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Reviewed-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Link: https://lore.kernel.org/r/20240215155009.94493-1-mheyne@amazon.de Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com> --- fs/ext4/resize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 2d022055675c..9edc8da921f4 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1551,7 +1551,8 @@ static int ext4_flex_group_add(struct super_block *sb, int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); - int meta_bg = ext4_has_feature_meta_bg(sb); + int meta_bg = ext4_has_feature_meta_bg(sb) && + gdb_num >= le32_to_cpu(es->s_first_meta_bg); sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - ext4_group_first_block_no(sb, 0); sector_t old_gdb = 0; -- 2.31.1

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[PATCH openEuler-22.03-LTS-SP1] ext4: fix corruption during on-line resize
by Zhihao Cheng 21 May '24

21 May '24

From: Maximilian Heyne <mheyne(a)amazon.de> stable inclusion from stable-v5.10.215 commit e8e8b197317228b5089ed9e7802dadf3ccaa027a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CF CVE: CVE-2024-35807 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit a6b3bfe176e8a5b05ec4447404e412c2a3fc92cc ] We observed a corruption during on-line resize of a file system that is larger than 16 TiB with 4k block size. With having more then 2^32 blocks resize_inode is turned off by default by mke2fs. The issue can be reproduced on a smaller file system for convenience by explicitly turning off resize_inode. An on-line resize across an 8 GiB boundary (the size of a meta block group in this setup) then leads to a corruption: dev=/dev/<some_dev> # should be >= 16 GiB mkdir -p /corruption /sbin/mke2fs -t ext4 -b 4096 -O ^resize_inode $dev $((2 * 2**21 - 2**15)) mount -t ext4 $dev /corruption dd if=/dev/zero bs=4096 of=/corruption/test count=$((2*2**21 - 4*2**15)) sha1sum /corruption/test # 79d2658b39dcfd77274e435b0934028adafaab11 /corruption/test /sbin/resize2fs $dev $((2*2**21)) # drop page cache to force reload the block from disk echo 1 > /proc/sys/vm/drop_caches sha1sum /corruption/test # 3c2abc63cbf1a94c9e6977e0fbd72cd832c4d5c3 /corruption/test 2^21 = 2^15*2^6 equals 8 GiB whereof 2^15 is the number of blocks per block group and 2^6 are the number of block groups that make a meta block group. The last checksum might be different depending on how the file is laid out across the physical blocks. The actual corruption occurs at physical block 63*2^15 = 2064384 which would be the location of the backup of the meta block group's block descriptor. During the on-line resize the file system will be converted to meta_bg starting at s_first_meta_bg which is 2 in the example - meaning all block groups after 16 GiB. However, in ext4_flex_group_add we might add block groups that are not part of the first meta block group yet. In the reproducer we achieved this by substracting the size of a whole block group from the point where the meta block group would start. This must be considered when updating the backup block group descriptors to follow the non-meta_bg layout. The fix is to add a test whether the group to add is already part of the meta block group or not. Fixes: 01f795f9e0d67 ("ext4: add online resizing support for meta_bg and 64-bit file systems") Cc: <stable(a)vger.kernel.org> Signed-off-by: Maximilian Heyne <mheyne(a)amazon.de> Tested-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Reviewed-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Link: https://lore.kernel.org/r/20240215155009.94493-1-mheyne@amazon.de Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com> --- fs/ext4/resize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 2d022055675c..9edc8da921f4 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1551,7 +1551,8 @@ static int ext4_flex_group_add(struct super_block *sb, int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); - int meta_bg = ext4_has_feature_meta_bg(sb); + int meta_bg = ext4_has_feature_meta_bg(sb) && + gdb_num >= le32_to_cpu(es->s_first_meta_bg); sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - ext4_group_first_block_no(sb, 0); sector_t old_gdb = 0; -- 2.31.1

2 1

[PATCH openEuler-22.03-LTS] ext4: fix corruption during on-line resize
by Zhihao Cheng 21 May '24

21 May '24

From: Maximilian Heyne <mheyne(a)amazon.de> stable inclusion from stable-v5.10.215 commit e8e8b197317228b5089ed9e7802dadf3ccaa027a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CF CVE: CVE-2024-35807 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit a6b3bfe176e8a5b05ec4447404e412c2a3fc92cc ] We observed a corruption during on-line resize of a file system that is larger than 16 TiB with 4k block size. With having more then 2^32 blocks resize_inode is turned off by default by mke2fs. The issue can be reproduced on a smaller file system for convenience by explicitly turning off resize_inode. An on-line resize across an 8 GiB boundary (the size of a meta block group in this setup) then leads to a corruption: dev=/dev/<some_dev> # should be >= 16 GiB mkdir -p /corruption /sbin/mke2fs -t ext4 -b 4096 -O ^resize_inode $dev $((2 * 2**21 - 2**15)) mount -t ext4 $dev /corruption dd if=/dev/zero bs=4096 of=/corruption/test count=$((2*2**21 - 4*2**15)) sha1sum /corruption/test # 79d2658b39dcfd77274e435b0934028adafaab11 /corruption/test /sbin/resize2fs $dev $((2*2**21)) # drop page cache to force reload the block from disk echo 1 > /proc/sys/vm/drop_caches sha1sum /corruption/test # 3c2abc63cbf1a94c9e6977e0fbd72cd832c4d5c3 /corruption/test 2^21 = 2^15*2^6 equals 8 GiB whereof 2^15 is the number of blocks per block group and 2^6 are the number of block groups that make a meta block group. The last checksum might be different depending on how the file is laid out across the physical blocks. The actual corruption occurs at physical block 63*2^15 = 2064384 which would be the location of the backup of the meta block group's block descriptor. During the on-line resize the file system will be converted to meta_bg starting at s_first_meta_bg which is 2 in the example - meaning all block groups after 16 GiB. However, in ext4_flex_group_add we might add block groups that are not part of the first meta block group yet. In the reproducer we achieved this by substracting the size of a whole block group from the point where the meta block group would start. This must be considered when updating the backup block group descriptors to follow the non-meta_bg layout. The fix is to add a test whether the group to add is already part of the meta block group or not. Fixes: 01f795f9e0d67 ("ext4: add online resizing support for meta_bg and 64-bit file systems") Cc: <stable(a)vger.kernel.org> Signed-off-by: Maximilian Heyne <mheyne(a)amazon.de> Tested-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Reviewed-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Link: https://lore.kernel.org/r/20240215155009.94493-1-mheyne@amazon.de Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com> Signed-off-by: Zhihao Cheng <chengzhihao(a)huaweicloud.com> --- fs/ext4/resize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 2d022055675c..9edc8da921f4 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1551,7 +1551,8 @@ static int ext4_flex_group_add(struct super_block *sb, int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); - int meta_bg = ext4_has_feature_meta_bg(sb); + int meta_bg = ext4_has_feature_meta_bg(sb) && + gdb_num >= le32_to_cpu(es->s_first_meta_bg); sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - ext4_group_first_block_no(sb, 0); sector_t old_gdb = 0; -- 2.31.1

2 1

[PATCH OLK-5.10] ext4: fix corruption during on-line resize
by Zhihao Cheng 21 May '24

21 May '24

From: Maximilian Heyne <mheyne(a)amazon.de> stable inclusion from stable-v5.10.215 commit e8e8b197317228b5089ed9e7802dadf3ccaa027a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9Q9CF CVE: CVE-2024-35807 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit a6b3bfe176e8a5b05ec4447404e412c2a3fc92cc ] We observed a corruption during on-line resize of a file system that is larger than 16 TiB with 4k block size. With having more then 2^32 blocks resize_inode is turned off by default by mke2fs. The issue can be reproduced on a smaller file system for convenience by explicitly turning off resize_inode. An on-line resize across an 8 GiB boundary (the size of a meta block group in this setup) then leads to a corruption: dev=/dev/<some_dev> # should be >= 16 GiB mkdir -p /corruption /sbin/mke2fs -t ext4 -b 4096 -O ^resize_inode $dev $((2 * 2**21 - 2**15)) mount -t ext4 $dev /corruption dd if=/dev/zero bs=4096 of=/corruption/test count=$((2*2**21 - 4*2**15)) sha1sum /corruption/test # 79d2658b39dcfd77274e435b0934028adafaab11 /corruption/test /sbin/resize2fs $dev $((2*2**21)) # drop page cache to force reload the block from disk echo 1 > /proc/sys/vm/drop_caches sha1sum /corruption/test # 3c2abc63cbf1a94c9e6977e0fbd72cd832c4d5c3 /corruption/test 2^21 = 2^15*2^6 equals 8 GiB whereof 2^15 is the number of blocks per block group and 2^6 are the number of block groups that make a meta block group. The last checksum might be different depending on how the file is laid out across the physical blocks. The actual corruption occurs at physical block 63*2^15 = 2064384 which would be the location of the backup of the meta block group's block descriptor. During the on-line resize the file system will be converted to meta_bg starting at s_first_meta_bg which is 2 in the example - meaning all block groups after 16 GiB. However, in ext4_flex_group_add we might add block groups that are not part of the first meta block group yet. In the reproducer we achieved this by substracting the size of a whole block group from the point where the meta block group would start. This must be considered when updating the backup block group descriptors to follow the non-meta_bg layout. The fix is to add a test whether the group to add is already part of the meta block group or not. Fixes: 01f795f9e0d67 ("ext4: add online resizing support for meta_bg and 64-bit file systems") Cc: <stable(a)vger.kernel.org> Signed-off-by: Maximilian Heyne <mheyne(a)amazon.de> Tested-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Reviewed-by: Srivathsa Dara <srivathsa.d.dara(a)oracle.com> Link: https://lore.kernel.org/r/20240215155009.94493-1-mheyne@amazon.de Signed-off-by: Theodore Ts'o <tytso(a)mit.edu> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com> --- fs/ext4/resize.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 2d022055675c..9edc8da921f4 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1551,7 +1551,8 @@ static int ext4_flex_group_add(struct super_block *sb, int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); int gdb_num_end = ((group + flex_gd->count - 1) / EXT4_DESC_PER_BLOCK(sb)); - int meta_bg = ext4_has_feature_meta_bg(sb); + int meta_bg = ext4_has_feature_meta_bg(sb) && + gdb_num >= le32_to_cpu(es->s_first_meta_bg); sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - ext4_group_first_block_no(sb, 0); sector_t old_gdb = 0; -- 2.31.1

2 1

[PATCH openEuler-1.0-LTS] arm64: asm-bug: Add .align 2 to the end of __BUG_ENTRY
by Li Zetao 21 May '24

21 May '24

From: Jiangfeng Xiao <xiaojiangfeng(a)huawei.com> Offering: HULK hulk inclusion category: bugfix bugzilla: NA Reference: https://lore.kernel.org/all/1716212077-43826-1-git-send-email-xiaojiangfeng… ---------------------------------------- When CONFIG_DEBUG_BUGVERBOSE=n, we fail to add necessary padding bytes to bug_table entries, and as a result the last entry in a bug table will be ignored, potentially leading to an unexpected panic(). All prior entries in the table will be handled correctly. The arm64 ABI requires that struct fields of up to 8 bytes are naturally-aligned, with padding added within a struct such that struct are suitably aligned within arrays. When CONFIG_DEBUG_BUGVERPOSE=y, the layout of a bug_entry is: struct bug_entry { signed int bug_addr_disp; // 4 bytes signed int file_disp; // 4 bytes unsigned short line; // 2 bytes unsigned short flags; // 2 bytes } ... with 12 bytes total, requiring 4-byte alignment. When CONFIG_DEBUG_BUGVERBOSE=n, the layout of a bug_entry is: struct bug_entry { signed int bug_addr_disp; // 4 bytes unsigned short flags; // 2 bytes < implicit padding > // 2 bytes } ... with 8 bytes total, with 6 bytes of data and 2 bytes of trailing padding, requiring 4-byte alginment. When we create a bug_entry in assembly, we align the start of the entry to 4 bytes, which implicitly handles padding for any prior entries. However, we do not align the end of the entry, and so when CONFIG_DEBUG_BUGVERBOSE=n, the final entry lacks the trailing padding bytes. For the main kernel image this is not a problem as find_bug() doesn't depend on the trailing padding bytes when searching for entries: for (bug = __start___bug_table; bug < __stop___bug_table; ++bug) if (bugaddr == bug_addr(bug)) return bug; However for modules, module_bug_finalize() depends on the trailing bytes when calculating the number of entries: mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry); ... and as the last bug_entry lacks the necessary padding bytes, this entry will not be counted, e.g. in the case of a single entry: sechdrs[i].sh_size == 6 sizeof(struct bug_entry) == 8; sechdrs[i].sh_size / sizeof(struct bug_entry) == 0; Consequently module_find_bug() will miss the last bug_entry when it does: for (i = 0; i < mod->num_bugs; ++i, ++bug) if (bugaddr == bug_addr(bug)) goto out; ... which can lead to a kenrel panic due to an unhandled bug. This can be demonstrated with the following module: static int __init buginit(void) { WARN(1, "hello\n"); return 0; } static void __exit bugexit(void) { } module_init(buginit); module_exit(bugexit); MODULE_LICENSE("GPL"); ... which will trigger a kernel panic when loaded: ------------[ cut here ]------------ hello Unexpected kernel BRK exception at EL1 Internal error: BRK handler: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: hello(O+) CPU: 0 PID: 50 Comm: insmod Tainted: G O 6.9.1 #8 Hardware name: linux,dummy-virt (DT) pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : buginit+0x18/0x1000 [hello] lr : buginit+0x18/0x1000 [hello] sp : ffff800080533ae0 x29: ffff800080533ae0 x28: 0000000000000000 x27: 0000000000000000 x26: ffffaba8c4e70510 x25: ffff800080533c30 x24: ffffaba8c4a28a58 x23: 0000000000000000 x22: 0000000000000000 x21: ffff3947c0eab3c0 x20: ffffaba8c4e3f000 x19: ffffaba846464000 x18: 0000000000000006 x17: 0000000000000000 x16: ffffaba8c2492834 x15: 0720072007200720 x14: 0720072007200720 x13: ffffaba8c49b27c8 x12: 0000000000000312 x11: 0000000000000106 x10: ffffaba8c4a0a7c8 x9 : ffffaba8c49b27c8 x8 : 00000000ffffefff x7 : ffffaba8c4a0a7c8 x6 : 80000000fffff000 x5 : 0000000000000107 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff3947c0eab3c0 Call trace: buginit+0x18/0x1000 [hello] do_one_initcall+0x80/0x1c8 do_init_module+0x60/0x218 load_module+0x1ba4/0x1d70 __do_sys_init_module+0x198/0x1d0 __arm64_sys_init_module+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x34/0xd8 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x190/0x194 Code: d0ffffe0 910003fd 91000000 9400000b (d4210000) ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: BRK handler: Fatal exception Fix this by always aligning the end of a bug_entry to 4 bytes, which is correct regardless of CONFIG_DEBUG_BUGVERBOSE. Fixes: 9fb7410f955f ("arm64/BUG: Use BRK instruction for generic BUG traps") Signed-off-by: Yuanbin Xie <xieyuanbin1(a)huawei.com> Signed-off-by: Jiangfeng Xiao <xiaojiangfeng(a)huawei.com> Reviewed-by: Mark Rutland <mark.rutland(a)arm.com> Signed-off-by: Li Zetao <lizetao1(a)huawei.com> --- arch/arm64/include/asm/asm-bug.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/include/asm/asm-bug.h b/arch/arm64/include/asm/asm-bug.h index b3552c4a405f2..13a5abaac36bf 100644 --- a/arch/arm64/include/asm/asm-bug.h +++ b/arch/arm64/include/asm/asm-bug.h @@ -39,6 +39,7 @@ 14470: .long 14471f - 14470b; \ _BUGVERBOSE_LOCATION(__FILE__, __LINE__) \ .short flags; \ + .align 2; \ .popsection; \ 14471: #else -- 2.34.1

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