| Message ID | 1635750020-2275-1-git-send-email-xuyang2018.jy@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] xfs: Fix the free logic of state in xfs_attr_node_hasname | expand |
Hi Darrick, Allison Any comment? Best Regards Yang Xu > When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine. > Adding a getxattr operation after xattr corrupted, I can reproduce it 100%. > > The deadlock as below: > [983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080 > [ 983.923405] Call Trace: > [ 983.923410] __schedule+0x2c4/0x700 > [ 983.923412] schedule+0x37/0xa0 > [ 983.923414] schedule_timeout+0x274/0x300 > [ 983.923416] __down+0x9b/0xf0 > [ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > [ 983.923453] down+0x3b/0x50 > [ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs] > [ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > [ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs] > [ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs] > [ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs] > [ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs] > [ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs] > [ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs] > [ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs] > [ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs] > [ 983.923624] ? kmem_cache_alloc+0x12e/0x270 > [ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs] > [ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs] > [ 983.923664] xfs_attr_set+0x273/0x320 [xfs] > [ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs] > [ 983.923686] __vfs_removexattr+0x4d/0x60 > [ 983.923688] __vfs_removexattr_locked+0xac/0x130 > [ 983.923689] vfs_removexattr+0x4e/0xf0 > [ 983.923690] removexattr+0x4d/0x80 > [ 983.923693] ? __check_object_size+0xa8/0x16b > [ 983.923695] ? strncpy_from_user+0x47/0x1a0 > [ 983.923696] ? getname_flags+0x6a/0x1e0 > [ 983.923697] ? _cond_resched+0x15/0x30 > [ 983.923699] ? __sb_start_write+0x1e/0x70 > [ 983.923700] ? mnt_want_write+0x28/0x50 > [ 983.923701] path_removexattr+0x9b/0xb0 > [ 983.923702] __x64_sys_removexattr+0x17/0x20 > [ 983.923704] do_syscall_64+0x5b/0x1a0 > [ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca > [ 983.923707] RIP: 0033:0x7f080f10ee1b > > When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in > xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it > free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job. > > Then subsequent removexattr will hang because of it. > > This bug was introduced by kernel commit 07120f1abdff ("xfs: Add xfs_has_attr and subroutines"). > It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state > in this case. But xfs_attr_node_hasname will free state itself instead of caller if > xfs_da3_node_lookup_int fails. > > Fix this bug by moving the step of free state into caller. > > Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and > xfs_attr_node_removename_setup function because we should free state ourselves. > > Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines") > Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com> > --- > fs/xfs/libxfs/xfs_attr.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > index fbc9d816882c..23523b802539 100644 > --- a/fs/xfs/libxfs/xfs_attr.c > +++ b/fs/xfs/libxfs/xfs_attr.c > @@ -1077,21 +1077,18 @@ xfs_attr_node_hasname( > > state = xfs_da_state_alloc(args); > if (statep != NULL) > - *statep = NULL; > + *statep = state; > > /* > * Search to see if name exists, and get back a pointer to it. > */ > error = xfs_da3_node_lookup_int(state,&retval); > - if (error) { > - xfs_da_state_free(state); > - return error; > - } > + if (error) > + retval = error; > > - if (statep != NULL) > - *statep = state; > - else > + if (!statep) > xfs_da_state_free(state); > + > return retval; > } > > @@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr( > */ > retval = xfs_attr_node_hasname(args,&dac->da_state); > if (retval != -ENOATTR&& retval != -EEXIST) > - return retval; > + goto error; > > if (retval == -ENOATTR&& (args->attr_flags& XATTR_REPLACE)) > goto error; > @@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup( > > error = xfs_attr_node_hasname(args, state); > if (error != -EEXIST) > - return error; > + goto out; > error = 0; > > ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL);
on 2021/11/5 11:12, xuyang2018.jy@fujitsu.com wrote: > Hi Darrick, Allison > > Any comment? Ping. > > Best Regards > Yang Xu >> When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine. >> Adding a getxattr operation after xattr corrupted, I can reproduce it 100%. >> >> The deadlock as below: >> [983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080 >> [ 983.923405] Call Trace: >> [ 983.923410] __schedule+0x2c4/0x700 >> [ 983.923412] schedule+0x37/0xa0 >> [ 983.923414] schedule_timeout+0x274/0x300 >> [ 983.923416] __down+0x9b/0xf0 >> [ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] >> [ 983.923453] down+0x3b/0x50 >> [ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs] >> [ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] >> [ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs] >> [ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs] >> [ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs] >> [ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs] >> [ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs] >> [ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs] >> [ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs] >> [ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs] >> [ 983.923624] ? kmem_cache_alloc+0x12e/0x270 >> [ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs] >> [ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs] >> [ 983.923664] xfs_attr_set+0x273/0x320 [xfs] >> [ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs] >> [ 983.923686] __vfs_removexattr+0x4d/0x60 >> [ 983.923688] __vfs_removexattr_locked+0xac/0x130 >> [ 983.923689] vfs_removexattr+0x4e/0xf0 >> [ 983.923690] removexattr+0x4d/0x80 >> [ 983.923693] ? __check_object_size+0xa8/0x16b >> [ 983.923695] ? strncpy_from_user+0x47/0x1a0 >> [ 983.923696] ? getname_flags+0x6a/0x1e0 >> [ 983.923697] ? _cond_resched+0x15/0x30 >> [ 983.923699] ? __sb_start_write+0x1e/0x70 >> [ 983.923700] ? mnt_want_write+0x28/0x50 >> [ 983.923701] path_removexattr+0x9b/0xb0 >> [ 983.923702] __x64_sys_removexattr+0x17/0x20 >> [ 983.923704] do_syscall_64+0x5b/0x1a0 >> [ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca >> [ 983.923707] RIP: 0033:0x7f080f10ee1b >> >> When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in >> xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it >> free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job. >> >> Then subsequent removexattr will hang because of it. >> >> This bug was introduced by kernel commit 07120f1abdff ("xfs: Add xfs_has_attr and subroutines"). >> It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state >> in this case. But xfs_attr_node_hasname will free state itself instead of caller if >> xfs_da3_node_lookup_int fails. >> >> Fix this bug by moving the step of free state into caller. >> >> Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and >> xfs_attr_node_removename_setup function because we should free state ourselves. >> >> Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines") >> Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com> >> --- >> fs/xfs/libxfs/xfs_attr.c | 17 +++++++---------- >> 1 file changed, 7 insertions(+), 10 deletions(-) >> >> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c >> index fbc9d816882c..23523b802539 100644 >> --- a/fs/xfs/libxfs/xfs_attr.c >> +++ b/fs/xfs/libxfs/xfs_attr.c >> @@ -1077,21 +1077,18 @@ xfs_attr_node_hasname( >> >> state = xfs_da_state_alloc(args); >> if (statep != NULL) >> - *statep = NULL; >> + *statep = state; >> >> /* >> * Search to see if name exists, and get back a pointer to it. >> */ >> error = xfs_da3_node_lookup_int(state,&retval); >> - if (error) { >> - xfs_da_state_free(state); >> - return error; >> - } >> + if (error) >> + retval = error; >> >> - if (statep != NULL) >> - *statep = state; >> - else >> + if (!statep) >> xfs_da_state_free(state); >> + >> return retval; >> } >> >> @@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr( >> */ >> retval = xfs_attr_node_hasname(args,&dac->da_state); >> if (retval != -ENOATTR&& retval != -EEXIST) >> - return retval; >> + goto error; >> >> if (retval == -ENOATTR&& (args->attr_flags& XATTR_REPLACE)) >> goto error; >> @@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup( >> >> error = xfs_attr_node_hasname(args, state); >> if (error != -EEXIST) >> - return error; >> + goto out; >> error = 0; >> >> ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL); > >
On Mon, Nov 15, 2021 at 01:27:28AM +0000, xuyang2018.jy@fujitsu.com wrote: > on 2021/11/5 11:12, xuyang2018.jy@fujitsu.com wrote: > > Hi Darrick, Allison > > > > Any comment? > Ping. FWIW I think it looks fine, but I was kinda wondering if Allison had any input? --D > > > > Best Regards > > Yang Xu > >> When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine. > >> Adding a getxattr operation after xattr corrupted, I can reproduce it 100%. > >> > >> The deadlock as below: > >> [983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080 > >> [ 983.923405] Call Trace: > >> [ 983.923410] __schedule+0x2c4/0x700 > >> [ 983.923412] schedule+0x37/0xa0 > >> [ 983.923414] schedule_timeout+0x274/0x300 > >> [ 983.923416] __down+0x9b/0xf0 > >> [ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > >> [ 983.923453] down+0x3b/0x50 > >> [ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs] > >> [ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > >> [ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs] > >> [ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs] > >> [ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs] > >> [ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs] > >> [ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs] > >> [ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs] > >> [ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs] > >> [ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs] > >> [ 983.923624] ? kmem_cache_alloc+0x12e/0x270 > >> [ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs] > >> [ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs] > >> [ 983.923664] xfs_attr_set+0x273/0x320 [xfs] > >> [ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs] > >> [ 983.923686] __vfs_removexattr+0x4d/0x60 > >> [ 983.923688] __vfs_removexattr_locked+0xac/0x130 > >> [ 983.923689] vfs_removexattr+0x4e/0xf0 > >> [ 983.923690] removexattr+0x4d/0x80 > >> [ 983.923693] ? __check_object_size+0xa8/0x16b > >> [ 983.923695] ? strncpy_from_user+0x47/0x1a0 > >> [ 983.923696] ? getname_flags+0x6a/0x1e0 > >> [ 983.923697] ? _cond_resched+0x15/0x30 > >> [ 983.923699] ? __sb_start_write+0x1e/0x70 > >> [ 983.923700] ? mnt_want_write+0x28/0x50 > >> [ 983.923701] path_removexattr+0x9b/0xb0 > >> [ 983.923702] __x64_sys_removexattr+0x17/0x20 > >> [ 983.923704] do_syscall_64+0x5b/0x1a0 > >> [ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca > >> [ 983.923707] RIP: 0033:0x7f080f10ee1b > >> > >> When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in > >> xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it > >> free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job. > >> > >> Then subsequent removexattr will hang because of it. > >> > >> This bug was introduced by kernel commit 07120f1abdff ("xfs: Add xfs_has_attr and subroutines"). > >> It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state > >> in this case. But xfs_attr_node_hasname will free state itself instead of caller if > >> xfs_da3_node_lookup_int fails. > >> > >> Fix this bug by moving the step of free state into caller. > >> > >> Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and > >> xfs_attr_node_removename_setup function because we should free state ourselves. > >> > >> Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines") > >> Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com> > >> --- > >> fs/xfs/libxfs/xfs_attr.c | 17 +++++++---------- > >> 1 file changed, 7 insertions(+), 10 deletions(-) > >> > >> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > >> index fbc9d816882c..23523b802539 100644 > >> --- a/fs/xfs/libxfs/xfs_attr.c > >> +++ b/fs/xfs/libxfs/xfs_attr.c > >> @@ -1077,21 +1077,18 @@ xfs_attr_node_hasname( > >> > >> state = xfs_da_state_alloc(args); > >> if (statep != NULL) > >> - *statep = NULL; > >> + *statep = state; > >> > >> /* > >> * Search to see if name exists, and get back a pointer to it. > >> */ > >> error = xfs_da3_node_lookup_int(state,&retval); > >> - if (error) { > >> - xfs_da_state_free(state); > >> - return error; > >> - } > >> + if (error) > >> + retval = error; > >> > >> - if (statep != NULL) > >> - *statep = state; > >> - else > >> + if (!statep) > >> xfs_da_state_free(state); > >> + > >> return retval; > >> } > >> > >> @@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr( > >> */ > >> retval = xfs_attr_node_hasname(args,&dac->da_state); > >> if (retval != -ENOATTR&& retval != -EEXIST) > >> - return retval; > >> + goto error; > >> > >> if (retval == -ENOATTR&& (args->attr_flags& XATTR_REPLACE)) > >> goto error; > >> @@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup( > >> > >> error = xfs_attr_node_hasname(args, state); > >> if (error != -EEXIST) > >> - return error; > >> + goto out; > >> error = 0; > >> > >> ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL); > > > >
On Tue, Nov 16, 2021 at 05:58:11PM -0800, Darrick J. Wong wrote: > On Mon, Nov 15, 2021 at 01:27:28AM +0000, xuyang2018.jy@fujitsu.com wrote: > > on 2021/11/5 11:12, xuyang2018.jy@fujitsu.com wrote: > > > Hi Darrick, Allison > > > > > > Any comment? > > Ping. > > FWIW I think it looks fine, but I was kinda wondering if Allison had any > input? Evidently I also pushed this into 5.16 but never RVBd this (???) on list. Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > > --D > > > > > > > Best Regards > > > Yang Xu > > >> When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine. > > >> Adding a getxattr operation after xattr corrupted, I can reproduce it 100%. > > >> > > >> The deadlock as below: > > >> [983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080 > > >> [ 983.923405] Call Trace: > > >> [ 983.923410] __schedule+0x2c4/0x700 > > >> [ 983.923412] schedule+0x37/0xa0 > > >> [ 983.923414] schedule_timeout+0x274/0x300 > > >> [ 983.923416] __down+0x9b/0xf0 > > >> [ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > > >> [ 983.923453] down+0x3b/0x50 > > >> [ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs] > > >> [ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] > > >> [ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs] > > >> [ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs] > > >> [ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs] > > >> [ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs] > > >> [ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs] > > >> [ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs] > > >> [ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs] > > >> [ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs] > > >> [ 983.923624] ? kmem_cache_alloc+0x12e/0x270 > > >> [ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs] > > >> [ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs] > > >> [ 983.923664] xfs_attr_set+0x273/0x320 [xfs] > > >> [ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs] > > >> [ 983.923686] __vfs_removexattr+0x4d/0x60 > > >> [ 983.923688] __vfs_removexattr_locked+0xac/0x130 > > >> [ 983.923689] vfs_removexattr+0x4e/0xf0 > > >> [ 983.923690] removexattr+0x4d/0x80 > > >> [ 983.923693] ? __check_object_size+0xa8/0x16b > > >> [ 983.923695] ? strncpy_from_user+0x47/0x1a0 > > >> [ 983.923696] ? getname_flags+0x6a/0x1e0 > > >> [ 983.923697] ? _cond_resched+0x15/0x30 > > >> [ 983.923699] ? __sb_start_write+0x1e/0x70 > > >> [ 983.923700] ? mnt_want_write+0x28/0x50 > > >> [ 983.923701] path_removexattr+0x9b/0xb0 > > >> [ 983.923702] __x64_sys_removexattr+0x17/0x20 > > >> [ 983.923704] do_syscall_64+0x5b/0x1a0 > > >> [ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca > > >> [ 983.923707] RIP: 0033:0x7f080f10ee1b > > >> > > >> When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in > > >> xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it > > >> free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job. > > >> > > >> Then subsequent removexattr will hang because of it. > > >> > > >> This bug was introduced by kernel commit 07120f1abdff ("xfs: Add xfs_has_attr and subroutines"). > > >> It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state > > >> in this case. But xfs_attr_node_hasname will free state itself instead of caller if > > >> xfs_da3_node_lookup_int fails. > > >> > > >> Fix this bug by moving the step of free state into caller. > > >> > > >> Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and > > >> xfs_attr_node_removename_setup function because we should free state ourselves. > > >> > > >> Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines") > > >> Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com> > > >> --- > > >> fs/xfs/libxfs/xfs_attr.c | 17 +++++++---------- > > >> 1 file changed, 7 insertions(+), 10 deletions(-) > > >> > > >> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > > >> index fbc9d816882c..23523b802539 100644 > > >> --- a/fs/xfs/libxfs/xfs_attr.c > > >> +++ b/fs/xfs/libxfs/xfs_attr.c > > >> @@ -1077,21 +1077,18 @@ xfs_attr_node_hasname( > > >> > > >> state = xfs_da_state_alloc(args); > > >> if (statep != NULL) > > >> - *statep = NULL; > > >> + *statep = state; > > >> > > >> /* > > >> * Search to see if name exists, and get back a pointer to it. > > >> */ > > >> error = xfs_da3_node_lookup_int(state,&retval); > > >> - if (error) { > > >> - xfs_da_state_free(state); > > >> - return error; > > >> - } > > >> + if (error) > > >> + retval = error; > > >> > > >> - if (statep != NULL) > > >> - *statep = state; > > >> - else > > >> + if (!statep) > > >> xfs_da_state_free(state); > > >> + > > >> return retval; > > >> } > > >> > > >> @@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr( > > >> */ > > >> retval = xfs_attr_node_hasname(args,&dac->da_state); > > >> if (retval != -ENOATTR&& retval != -EEXIST) > > >> - return retval; > > >> + goto error; > > >> > > >> if (retval == -ENOATTR&& (args->attr_flags& XATTR_REPLACE)) > > >> goto error; > > >> @@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup( > > >> > > >> error = xfs_attr_node_hasname(args, state); > > >> if (error != -EEXIST) > > >> - return error; > > >> + goto out; > > >> error = 0; > > >> > > >> ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL); > > > > > >
diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index fbc9d816882c..23523b802539 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -1077,21 +1077,18 @@ xfs_attr_node_hasname( state = xfs_da_state_alloc(args); if (statep != NULL) - *statep = NULL; + *statep = state; /* * Search to see if name exists, and get back a pointer to it. */ error = xfs_da3_node_lookup_int(state, &retval); - if (error) { - xfs_da_state_free(state); - return error; - } + if (error) + retval = error; - if (statep != NULL) - *statep = state; - else + if (!statep) xfs_da_state_free(state); + return retval; } @@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr( */ retval = xfs_attr_node_hasname(args, &dac->da_state); if (retval != -ENOATTR && retval != -EEXIST) - return retval; + goto error; if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE)) goto error; @@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup( error = xfs_attr_node_hasname(args, state); if (error != -EEXIST) - return error; + goto out; error = 0; ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL);
When testing xfstests xfs/126 on lastest upstream kernel, it will hang on some machine. Adding a getxattr operation after xattr corrupted, I can reproduce it 100%. The deadlock as below: [983.923403] task:setfattr state:D stack: 0 pid:17639 ppid: 14687 flags:0x00000080 [ 983.923405] Call Trace: [ 983.923410] __schedule+0x2c4/0x700 [ 983.923412] schedule+0x37/0xa0 [ 983.923414] schedule_timeout+0x274/0x300 [ 983.923416] __down+0x9b/0xf0 [ 983.923451] ? xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] [ 983.923453] down+0x3b/0x50 [ 983.923471] xfs_buf_lock+0x33/0xf0 [xfs] [ 983.923490] xfs_buf_find.isra.29+0x3c8/0x5f0 [xfs] [ 983.923508] xfs_buf_get_map+0x4c/0x320 [xfs] [ 983.923525] xfs_buf_read_map+0x53/0x310 [xfs] [ 983.923541] ? xfs_da_read_buf+0xcf/0x120 [xfs] [ 983.923560] xfs_trans_read_buf_map+0x1cf/0x360 [xfs] [ 983.923575] ? xfs_da_read_buf+0xcf/0x120 [xfs] [ 983.923590] xfs_da_read_buf+0xcf/0x120 [xfs] [ 983.923606] xfs_da3_node_read+0x1f/0x40 [xfs] [ 983.923621] xfs_da3_node_lookup_int+0x69/0x4a0 [xfs] [ 983.923624] ? kmem_cache_alloc+0x12e/0x270 [ 983.923637] xfs_attr_node_hasname+0x6e/0xa0 [xfs] [ 983.923651] xfs_has_attr+0x6e/0xd0 [xfs] [ 983.923664] xfs_attr_set+0x273/0x320 [xfs] [ 983.923683] xfs_xattr_set+0x87/0xd0 [xfs] [ 983.923686] __vfs_removexattr+0x4d/0x60 [ 983.923688] __vfs_removexattr_locked+0xac/0x130 [ 983.923689] vfs_removexattr+0x4e/0xf0 [ 983.923690] removexattr+0x4d/0x80 [ 983.923693] ? __check_object_size+0xa8/0x16b [ 983.923695] ? strncpy_from_user+0x47/0x1a0 [ 983.923696] ? getname_flags+0x6a/0x1e0 [ 983.923697] ? _cond_resched+0x15/0x30 [ 983.923699] ? __sb_start_write+0x1e/0x70 [ 983.923700] ? mnt_want_write+0x28/0x50 [ 983.923701] path_removexattr+0x9b/0xb0 [ 983.923702] __x64_sys_removexattr+0x17/0x20 [ 983.923704] do_syscall_64+0x5b/0x1a0 [ 983.923705] entry_SYSCALL_64_after_hwframe+0x65/0xca [ 983.923707] RIP: 0033:0x7f080f10ee1b When getxattr calls xfs_attr_node_get function, xfs_da3_node_lookup_int fails with EFSCORRUPTED in xfs_attr_node_hasname because we have use blocktrash to random it in xfs/126. So it free state in internal and xfs_attr_node_get doesn't do xfs_buf_trans release job. Then subsequent removexattr will hang because of it. This bug was introduced by kernel commit 07120f1abdff ("xfs: Add xfs_has_attr and subroutines"). It adds xfs_attr_node_hasname helper and said caller will be responsible for freeing the state in this case. But xfs_attr_node_hasname will free state itself instead of caller if xfs_da3_node_lookup_int fails. Fix this bug by moving the step of free state into caller. Also, use "goto error/out" instead of returning error directly in xfs_attr_node_addname_find_attr and xfs_attr_node_removename_setup function because we should free state ourselves. Fixes: 07120f1abdff ("xfs: Add xfs_has_attr and subroutines") Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com> --- fs/xfs/libxfs/xfs_attr.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-)