CVE-2026-46080
Description
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: split transactions in dio completion to avoid credit exhaustion
During ocfs2 dio operations, JBD2 may report warnings via following call trace: ocfs2_dio_end_io_write ocfs2_mark_extent_written ocfs2_change_extent_flag ocfs2_split_extent ocfs2_try_to_merge_extent ocfs2_extend_rotate_transaction ocfs2_extend_trans jbd2__journal_restart start_this_handle output: JBD2: kworker/6:2 wants too many credits credits:5450 rsv_credits:0 max:5449
To prevent exceeding the credits limit, modify ocfs2_dio_end_io_write() to handle extents in a batch of transaction.
Additionally, relocate ocfs2_del_inode_from_orphan(). The orphan inode should only be removed from the orphan list after the extent tree update is complete. This ensures that if a crash occurs in the middle of extent tree updates, we won't leave stale blocks beyond EOF.
This patch also changes the logic for updating the inode size and removing orphan, making it similar to ext4_dio_write_end_io(). Both operations are performed only when everything looks good.
Finally, thanks to Jans and Joseph for providing the bug fix prototype and suggestions.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
In the Linux kernel's ocfs2, direct I/O completion could exceed JBD2 transaction credits, causing warnings; the fix splits transactions in dio completion.
Vulnerability
The Linux kernel's ocfs2 filesystem contained a bug in the direct I/O (DIO) completion path where ocfs2_dio_end_io_write() could attempt to update extent trees using a single JBD2 transaction that required more credits than allowed. This resulted in the journal layer (JBD2) issuing wants too many credits warnings and potential credit exhaustion, as shown in the backtrace: ocfs2_dio_end_io_write -> ocfs2_mark_extent_written -> ocfs2_split_extent -> ocfs2_try_to_merge_extent -> ocfs2_extend_rotate_transaction -> jbd2__journal_restart. The problem affected all versions of the Linux kernel with ocfs2 support prior to the fix.
Exploitation
An attacker would need write access to an ocfs2 filesystem (requiring either local file system write permissions or a mounted ocfs2 volume) and the ability to trigger DIO write operations that cause extent splitting and merging. The attack is triggered during normal DIO write completion, where the kernel worker thread (kworker) processes the extent modifications. No special network position or user interaction beyond initiating the writes is needed; the race condition is in the kernel's handling of transaction credits, not a traditional race window.
Impact
A successful exploitation could lead to a denial of service (DoS) via system instability or hang due to JBD2 transaction credit exhaustion. Additionally, the bug in orphan inode handling (ocfs2_del_inode_from_orphan() being called before extent tree updates) could cause stale blocks beyond EOF if a crash occurred during the window, potentially leading to file system corruption or data loss. The fix ensures the orphan is removed only after extent updates are complete, preventing this inconsistency.
Mitigation
The vulnerability is fixed in the Linux kernel stable branch by commit 069c3fb310e9 [1]. Affected users should update their kernel to a version containing this commit. According to the reference, the fix has been applied to the stable tree as of May 27, 2026. If unable to patch, there is no known workaround, as ocfs2 is a filesystem that requires the fix to avoid transaction credit exhaustion. The fix also aligns the logic for inode size update and orphan removal with ext4_dio_write_end_io, improving consistency.
AI Insight generated on May 27, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.
Affected products
1Patches
103c636a3edca9ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 7a65d5a36a3e12..4ff9f2b64fe950 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2278,7 +2280,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2295,18 +2297,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2327,24 +2317,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2352,19 +2343,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
069c3fb310e9ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 09146b43d1f07a..c6dbec1693b125 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2277,7 +2279,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2294,18 +2296,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2326,24 +2316,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2351,19 +2342,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
d647c5b2fbf8ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 09146b43d1f07a..c6dbec1693b125 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2277,7 +2279,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2294,18 +2296,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2326,24 +2316,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2351,19 +2342,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
886f97fa59d0ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 0d147f2b4e9f5e..5365fc7675de46 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2305,7 +2307,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2322,18 +2324,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2354,24 +2344,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2379,19 +2370,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
ea5bb1d20da7ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index de40a07bcb5269..ba58572dfe6350 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2301,7 +2303,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2318,18 +2320,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2350,24 +2340,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2375,19 +2366,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
886f97fa59d0ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 0d147f2b4e9f5e..5365fc7675de46 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2305,7 +2307,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2322,18 +2324,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2354,24 +2344,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2379,19 +2370,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
3c636a3edca9ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 7a65d5a36a3e12..4ff9f2b64fe950 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2278,7 +2280,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2295,18 +2297,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2327,24 +2317,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2352,19 +2343,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
ea5bb1d20da7ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index de40a07bcb5269..ba58572dfe6350 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2301,7 +2303,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2318,18 +2320,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2350,24 +2340,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2375,19 +2366,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
069c3fb310e9ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 09146b43d1f07a..c6dbec1693b125 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2277,7 +2279,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2294,18 +2296,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2326,24 +2316,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2351,19 +2342,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
d647c5b2fbf8ocfs2: split transactions in dio completion to avoid credit exhaustion
1 file changed · +45 −30
fs/ocfs2/aops.c+45 −30 modifieddiff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 09146b43d1f07a..c6dbec1693b125 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -37,6 +37,8 @@ #include "namei.h" #include "sysfile.h" +#define OCFS2_DIO_MARK_EXTENT_BATCH 200 + static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2277,7 +2279,7 @@ static int ocfs2_dio_end_io_write(struct inode *inode, struct ocfs2_alloc_context *meta_ac = NULL; handle_t *handle = NULL; loff_t end = offset + bytes; - int ret = 0, credits = 0; + int ret = 0, credits = 0, batch = 0; ocfs2_init_dealloc_ctxt(&dealloc); @@ -2294,18 +2296,6 @@ static int ocfs2_dio_end_io_write(struct inode *inode, goto out; } - /* Delete orphan before acquire i_rwsem. */ - if (dwc->dw_orphaned) { - BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); - - end = end > i_size_read(inode) ? end : 0; - - ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, - !!end, end); - if (ret < 0) - mlog_errno(ret); - } - down_write(&oi->ip_alloc_sem); di = (struct ocfs2_dinode *)di_bh->b_data; @@ -2326,24 +2316,25 @@ static int ocfs2_dio_end_io_write(struct inode *inode, credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list); - handle = ocfs2_start_trans(osb, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - mlog_errno(ret); - goto unlock; - } - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto commit; - } - list_for_each_entry(ue, &dwc->dw_zero_list, ue_node) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto commit; + } + } ret = ocfs2_assure_trans_credits(handle, credits); if (ret < 0) { mlog_errno(ret); - break; + goto commit; } ret = ocfs2_mark_extent_written(inode, &et, handle, ue->ue_cpos, 1, @@ -2351,19 +2342,44 @@ static int ocfs2_dio_end_io_write(struct inode *inode, meta_ac, &dealloc); if (ret < 0) { mlog_errno(ret); - break; + goto commit; + } + + if (++batch == OCFS2_DIO_MARK_EXTENT_BATCH) { + ocfs2_commit_trans(osb, handle); + handle = NULL; + batch = 0; } } if (end > i_size_read(inode)) { + if (!handle) { + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto unlock; + } + } ret = ocfs2_set_inode_size(handle, inode, di_bh, end); if (ret < 0) mlog_errno(ret); } + commit: - ocfs2_commit_trans(osb, handle); + if (handle) + ocfs2_commit_trans(osb, handle); unlock: up_write(&oi->ip_alloc_sem); + + /* everything looks good, let's start the cleanup */ + if (!ret && dwc->dw_orphaned) { + BUG_ON(dwc->dw_writer_pid != task_pid_nr(current)); + + ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0); + if (ret < 0) + mlog_errno(ret); + } ocfs2_inode_unlock(inode, 1); brelse(di_bh); out: -- cgit 1.3-korg
Vulnerability mechanics
Root cause
"A single JBD2 transaction in ocfs2_dio_end_io_write can exhaust journal credits when marking many extents as written during DIO completion."
Attack vector
An attacker who can trigger direct I/O (dio) writes on an OCFS2 filesystem can cause the kernel to attempt marking a large number of extents as written within a single JBD2 transaction. The call chain `ocfs2_dio_end_io_write` → `ocfs2_mark_extent_written` → ... → `jbd2__journal_restart` can request more credits than the journal's maximum (e.g., 5450 credits vs. max 5449), triggering a JBD2 warning and potentially stalling or corrupting the journal. No authentication or special privileges beyond write access to an OCFS2 mount are required.
Affected code
The vulnerability is in `fs/ocfs2/aops.c` in the function `ocfs2_dio_end_io_write`. The original code started a single JBD2 transaction for the entire extent-marking loop, which could exhaust journal credits when processing many extents. The patch also relocated the `ocfs2_del_inode_from_orphan()` call from before the extent tree update to after it.
What the fix does
The patch introduces `OCFS2_DIO_MARK_EXTENT_BATCH` (set to 200) and modifies the extent-marking loop to commit and restart the transaction after every batch of 200 extents, preventing any single transaction from exceeding the journal's credit limit. It also moves `ocfs2_del_inode_from_orphan()` to after the extent tree update and the `ip_alloc_sem` is released, so the orphan inode is only removed from the orphan list after all extent modifications succeed — this avoids leaving stale blocks beyond EOF if a crash occurs mid-update. The inode size update (`ocfs2_set_inode_size`) is now also conditional on a handle being available, and both size update and orphan deletion are performed only when all prior operations succeeded.
Preconditions
- inputAttacker must be able to perform direct I/O (DIO) writes on an OCFS2 filesystem
- configThe OCFS2 filesystem must be mounted and accessible to the attacker
Generated on May 27, 2026. Inputs: CWE entries + fix-commit diffs from this CVE's patches. Citations validated against bundle.
References
5- git.kernel.org/stable/c/069c3fb310e9336cf48cfdf8748a32c29fd0193dnvd
- git.kernel.org/stable/c/3c636a3edca9c3f180b3079f94fe7e115730d9c6nvd
- git.kernel.org/stable/c/886f97fa59d0bbfa9859fb1a66dd9e014b522d89nvd
- git.kernel.org/stable/c/d647c5b2fbf81560818dacade360abc8c00a9665nvd
- git.kernel.org/stable/c/ea5bb1d20da756e4f41a48dad42b2e7d6e73f71envd
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