maillist inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8RJA8 CVE: NA
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During growfs, if new ag in memory has been initialized, however sb_agcount has not been updated, if an error occurs at this time it will cause perag leaks as follows, these new AGs will not been freed during umount , because of these new AGs are not visible(that is included in mp->m_sb.sb_agcount).
unreferenced object 0xffff88810be40200 (size 512): comm "xfs_growfs", pid 857, jiffies 4294909093 hex dump (first 32 bytes): 00 c0 c1 05 81 88 ff ff 04 00 00 00 00 00 00 00 ................ 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 381741e2): [<ffffffff8191aef6>] __kmalloc+0x386/0x4f0 [<ffffffff82553e65>] kmem_alloc+0xb5/0x2f0 [<ffffffff8238dac5>] xfs_initialize_perag+0xc5/0x810 [<ffffffff824f679c>] xfs_growfs_data+0x9bc/0xbc0 [<ffffffff8250b90e>] xfs_file_ioctl+0x5fe/0x14d0 [<ffffffff81aa5194>] __x64_sys_ioctl+0x144/0x1c0 [<ffffffff83c3d81f>] do_syscall_64+0x3f/0xe0 [<ffffffff83e00087>] entry_SYSCALL_64_after_hwframe+0x62/0x6a unreferenced object 0xffff88810be40800 (size 512): comm "xfs_growfs", pid 857, jiffies 4294909093 hex dump (first 32 bytes): 20 00 00 00 00 00 00 00 57 ef be dc 00 00 00 00 .......W....... 10 08 e4 0b 81 88 ff ff 10 08 e4 0b 81 88 ff ff ................ backtrace (crc bde50e2d): [<ffffffff8191b43a>] __kmalloc_node+0x3da/0x540 [<ffffffff81814489>] kvmalloc_node+0x99/0x160 [<ffffffff8286acff>] bucket_table_alloc.isra.0+0x5f/0x400 [<ffffffff8286bdc5>] rhashtable_init+0x405/0x760 [<ffffffff8238dda3>] xfs_initialize_perag+0x3a3/0x810 [<ffffffff824f679c>] xfs_growfs_data+0x9bc/0xbc0 [<ffffffff8250b90e>] xfs_file_ioctl+0x5fe/0x14d0 [<ffffffff81aa5194>] __x64_sys_ioctl+0x144/0x1c0 [<ffffffff83c3d81f>] do_syscall_64+0x3f/0xe0 [<ffffffff83e00087>] entry_SYSCALL_64_after_hwframe+0x62/0x6a
Factor out xfs_free_unused_perag_range() from xfs_initialize_perag(), used for freeing unused perag within a specified range in error handling, included in the error path of the growfs failure.
Fixes: 1c1c6ebcf528 ("xfs: Replace per-ag array with a radix tree") Signed-off-by: Long Li leo.lilong@huawei.com Reviewed-by: Darrick J. Wong djwong@kernel.org --- fs/xfs/libxfs/xfs_ag.c | 36 ++++++++++++++++++++++++++---------- fs/xfs/libxfs/xfs_ag.h | 2 ++ fs/xfs/xfs_fsops.c | 5 ++++- 3 files changed, 32 insertions(+), 11 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_ag.c b/fs/xfs/libxfs/xfs_ag.c index cc10a3ca052f..18d9bb2ebe8e 100644 --- a/fs/xfs/libxfs/xfs_ag.c +++ b/fs/xfs/libxfs/xfs_ag.c @@ -332,6 +332,31 @@ xfs_agino_range( return __xfs_agino_range(mp, xfs_ag_block_count(mp, agno), first, last); }
+/* + * Free perag within the specified AG range, it is only used to free unused + * perags under the error handling path. + */ +void +xfs_free_unused_perag_range( + struct xfs_mount *mp, + xfs_agnumber_t agstart, + xfs_agnumber_t agend) +{ + struct xfs_perag *pag; + xfs_agnumber_t index; + + for (index = agstart; index < agend; index++) { + spin_lock(&mp->m_perag_lock); + pag = radix_tree_delete(&mp->m_perag_tree, index); + spin_unlock(&mp->m_perag_lock); + if (!pag) + break; + xfs_buf_hash_destroy(pag); + xfs_defer_drain_free(&pag->pag_intents_drain); + kmem_free(pag); + } +} + int xfs_initialize_perag( struct xfs_mount *mp, @@ -431,16 +456,7 @@ xfs_initialize_perag( kmem_free(pag); out_unwind_new_pags: /* unwind any prior newly initialized pags */ - for (index = first_initialised; index < agcount; index++) { - spin_lock(&mp->m_perag_lock); - pag = radix_tree_delete(&mp->m_perag_tree, index); - spin_unlock(&mp->m_perag_lock); - if (!pag) - break; - xfs_buf_hash_destroy(pag); - xfs_defer_drain_free(&pag->pag_intents_drain); - kmem_free(pag); - } + xfs_free_unused_perag_range(mp, first_initialised, agcount); return error; }
diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index 2e0aef87d633..40d7b6427afb 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -133,6 +133,8 @@ __XFS_AG_OPSTATE(prefers_metadata, PREFERS_METADATA) __XFS_AG_OPSTATE(allows_inodes, ALLOWS_INODES) __XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
+void xfs_free_unused_perag_range(struct xfs_mount *mp, xfs_agnumber_t agstart, + xfs_agnumber_t agend); int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount, xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi); int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno); diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index 7cb75cb6b8e9..55ea34b4a69a 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -153,7 +153,7 @@ xfs_growfs_data_private( error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata, -delta, 0, 0, &tp); if (error) - return error; + goto out_free_unused_perag;
last_pag = xfs_perag_get(mp, oagcount - 1); if (delta > 0) { @@ -227,6 +227,9 @@ xfs_growfs_data_private(
out_trans_cancel: xfs_trans_cancel(tp); +out_free_unused_perag: + if (nagcount > oagcount) + xfs_free_unused_perag_range(mp, oagcount, nagcount); return error; }