From c73370c677646e86fc4b1780fb07027bdf847375 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 28 Apr 2026 16:58:56 +0100 Subject: btrfs: tracepoints: fix sleep while in atomic context in btrfs_sync_file() The trace event btrfs_sync_file() is called in an atomic context (all trace events are) and its call to dput(), which is needed due to the call to dget_parent(), can sleep, triggering a kernel splat. This can be reproduced by enabling the trace event and running btrfs/056 from fstests for example. The splat shown in dmesg is the following: [53.919] BUG: sleeping function called from invalid context at fs/dcache.c:970 [53.947] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 32773, name: xfs_io [53.988] preempt_count: 2, expected: 0 [53.967] RCU nest depth: 0, expected: 0 [53.943] Preemption disabled at: [53.944] [<0000000000000000>] 0x0 [54.078] CPU: 0 UID: 0 PID: 32773 Comm: xfs_io Tainted: G W 7.1.0-rc1-btrfs-next-232+ #1 PREEMPT(full) [54.070] Tainted: [W]=WARN [54.071] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [54.072] Call Trace: [54.074] [54.076] dump_stack_lvl+0x56/0x80 [54.079] __might_resched.cold+0xd6/0x10f [54.072] dput.part.0+0x24/0x110 [54.078] trace_event_raw_event_btrfs_sync_file+0x75/0x140 [btrfs] [54.089] btrfs_sync_file+0x1ed/0x530 [btrfs] [54.087] ? __handle_mm_fault+0x8ae/0xed0 [54.089] btrfs_do_write_iter+0x172/0x210 [btrfs] [54.091] vfs_write+0x21f/0x450 [54.094] __x64_sys_pwrite64+0x8d/0xc0 [54.096] ? do_user_addr_fault+0x20c/0x670 [54.099] do_syscall_64+0x60/0xf20 [54.092] ? clear_bhb_loop+0x60/0xb0 [54.094] entry_SYSCALL_64_after_hwframe+0x76/0x7e So stop using dget_parent() and dput() and access the parent dentry directly as dentry->d_parent. This is also what ext4 is doing in its equivalent trace event ext4_sync_file_enter(). Fixes: a85b46db143f ("btrfs: tracepoints: get correct superblock from dentry in event btrfs_sync_file()") Reviewed-by: Boris Burkov Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- include/trace/events/btrfs.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'include/trace') diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index 8ad7a2d76c1d..ec1df8b94517 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -771,10 +771,8 @@ TRACE_EVENT(btrfs_sync_file, TP_fast_assign( struct dentry *dentry = file_dentry(file); struct inode *inode = file_inode(file); - struct dentry *parent = dget_parent(dentry); - struct inode *parent_inode = d_inode(parent); + struct inode *parent_inode = d_inode(dentry->d_parent); - dput(parent); TP_fast_assign_fsid(btrfs_sb(inode->i_sb)); __entry->ino = btrfs_ino(BTRFS_I(inode)); __entry->parent = btrfs_ino(BTRFS_I(parent_inode)); -- cgit v1.2.3 From 156ac2ec2ee77c44c4eb7439d6d165247ba12247 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 12 May 2026 13:33:48 +0100 Subject: netfs: Fix netfs_invalidate_folio() to clear dirty bit if all changes gone If a streaming write is made, this will leave the relevant modified folio in a not-uptodate, but dirty state with a netfs_folio struct hung off of folio->private indicating the dirty range. Subsequently truncating the file such that the dirty data in the folio is removed, but the first part of the folio theoretically remains will cause the netfs_folio struct to be discarded... but will leave the dirty flag set. If the folio is then read via mmap(), netfs_read_folio() will see that the page is dirty and jump to netfs_read_gaps() to fill in the missing bits. netfs_read_gaps(), however, expects there to be a netfs_folio struct present and can oops because truncate removed it. Fix this by calling folio_cancel_dirty() in netfs_invalidate_folio() in the event that all the dirty data in the folio is erased (as nfs does). Also add some tracepoints to log modifications to a dirty page. This can be reproduced with something like: dd if=/dev/zero of=/xfstest.test/foo bs=1M count=1 umount /xfstest.test mount /xfstest.test xfs_io -c "w 0xbbbf 0xf96c" \ -c "truncate 0xbbbf" \ -c "mmap -r 0xb000 0x11000" \ -c "mr 0xb000 0x11000" \ /xfstest.test/foo with fscaching disabled (otherwise streaming writes are suppressed) and a change to netfs_perform_write() to disallow streaming writes if the fd is open O_RDWR: if (//(file->f_mode & FMODE_READ) || <--- comment this out netfs_is_cache_enabled(ctx)) { It should be reproducible even without this change, but if prevents the above trivial xfs_io command from reproducing it. Note that the initial dd is important: the file must start out sufficiently large that the zero-point logic doesn't just clear the gaps because it knows there's nothing in the file to read yet. Unmounting and mounting is needed to clear the pagecache (there are other ways to do that that may also work). This was initially reproduced with the generic/522 xfstest on some patches that remove the FMODE_READ restriction. Fixes: 9ebff83e6481 ("netfs: Prep to use folio->private for write grouping and streaming write") Reported-by: Marc Dionne Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-12-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- fs/netfs/misc.c | 6 +++++- include/trace/events/netfs.h | 4 ++++ 2 files changed, 9 insertions(+), 1 deletion(-) (limited to 'include/trace') diff --git a/fs/netfs/misc.c b/fs/netfs/misc.c index 723571ca1b88..24b20e80e9a8 100644 --- a/fs/netfs/misc.c +++ b/fs/netfs/misc.c @@ -263,6 +263,7 @@ void netfs_invalidate_folio(struct folio *folio, size_t offset, size_t length) /* Move the start of the data. */ finfo->dirty_len = fend - iend; finfo->dirty_offset = offset; + trace_netfs_folio(folio, netfs_folio_trace_invalidate_front); return; } @@ -271,12 +272,14 @@ void netfs_invalidate_folio(struct folio *folio, size_t offset, size_t length) */ if (iend >= fend) { finfo->dirty_len = offset - fstart; + trace_netfs_folio(folio, netfs_folio_trace_invalidate_tail); return; } /* A partial write was split. The caller has already zeroed * it, so just absorb the hole. */ + trace_netfs_folio(folio, netfs_folio_trace_invalidate_middle); } return; @@ -284,8 +287,9 @@ erase_completely: netfs_put_group(netfs_folio_group(folio)); folio_detach_private(folio); folio_clear_uptodate(folio); + folio_cancel_dirty(folio); kfree(finfo); - return; + trace_netfs_folio(folio, netfs_folio_trace_invalidate_all); } EXPORT_SYMBOL(netfs_invalidate_folio); diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h index 8c936fc575d5..0b702f74aefe 100644 --- a/include/trace/events/netfs.h +++ b/include/trace/events/netfs.h @@ -194,6 +194,10 @@ EM(netfs_folio_trace_copy_to_cache, "mark-copy") \ EM(netfs_folio_trace_end_copy, "end-copy") \ EM(netfs_folio_trace_filled_gaps, "filled-gaps") \ + EM(netfs_folio_trace_invalidate_all, "inval-all") \ + EM(netfs_folio_trace_invalidate_front, "inval-front") \ + EM(netfs_folio_trace_invalidate_middle, "inval-mid") \ + EM(netfs_folio_trace_invalidate_tail, "inval-tail") \ EM(netfs_folio_trace_kill, "kill") \ EM(netfs_folio_trace_kill_cc, "kill-cc") \ EM(netfs_folio_trace_kill_g, "kill-g") \ -- cgit v1.2.3 From 7b4dcf1b9455a6e52ac7478b4057dbe10359576d Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 12 May 2026 13:33:50 +0100 Subject: netfs: Fix streaming write being overwritten In order to avoid reading whilst writing, netfslib will allow "streaming writes" in which dirty data is stored directly into folios without reading them first. Such folios are marked dirty but may not be marked uptodate. If a folio is entirely written by a streaming write, uptodate will be set, otherwise it will have a netfs_folio struct attached to ->private recording the dirty region. In the event that a partially written streaming write page is to be overwritten entirely by a single write(), netfs_perform_write() will try to copy over it, but doesn't discard the netfs_folio if it succeeds; further, it doesn't correctly handle a partial copy that overwrites some of the dirty data. Fix this by the following: (1) If the folio is successfully overwritten, free the netfs_folio struct before marking the page uptodate. (2) If the copy to the folio partially fails, but short of the dirty data, just ignore the copy. (3) If the copy partially fails and overwrites some of the dirty data, accept the copy, update the netfs_folio struct to record the new data. If the folio is now filled, free the netfs_folio and set uptodate, otherwise return a partial write. Found with: fsx -q -N 1000000 -p 10000 -o 128000 -l 600000 \ /xfstest.test/junk --replay-ops=junk.fsxops using the following as junk.fsxops: truncate 0x0 0 0x927c0 write 0x63fb8 0x53c8 0 copy_range 0xb704 0x19b9 0x24429 0x79380 write 0x2402b 0x144a2 0x90660 * write 0x204d5 0x140a0 0x927c0 * copy_range 0x1f72c 0x137d0 0x7a906 0x927c0 * read 0x00000 0x20000 0x9157c read 0x20000 0x20000 0x9157c read 0x40000 0x20000 0x9157c read 0x60000 0x20000 0x9157c read 0x7e1a0 0xcfb9 0x9157c on cifs with the default cache option. It shows folio 0x24 misbehaving if the FMODE_READ check is commented out in netfs_perform_write(): if (//(file->f_mode & FMODE_READ) || netfs_is_cache_enabled(ctx)) { and no fscache. This was initially found with the generic/522 xfstest. Fixes: 8f52de0077ba ("netfs: Reduce number of conditional branches in netfs_perform_write()") Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-14-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- fs/netfs/buffered_write.c | 47 ++++++++++++++++++++++++++++++++------------ include/trace/events/netfs.h | 3 +++ 2 files changed, 37 insertions(+), 13 deletions(-) (limited to 'include/trace') diff --git a/fs/netfs/buffered_write.c b/fs/netfs/buffered_write.c index 278aeb074e75..991552724868 100644 --- a/fs/netfs/buffered_write.c +++ b/fs/netfs/buffered_write.c @@ -246,18 +246,38 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, /* See if we can write a whole folio in one go. */ if (!maybe_trouble && offset == 0 && part >= flen) { copied = copy_folio_from_iter_atomic(folio, offset, part, iter); - if (unlikely(copied == 0)) + if (likely(copied == part)) { + if (finfo) { + trace = netfs_whole_folio_modify_filled; + goto folio_now_filled; + } + __netfs_set_group(folio, netfs_group); + folio_mark_uptodate(folio); + trace = netfs_whole_folio_modify; + goto copied; + } + if (copied == 0) goto copy_failed; - if (unlikely(copied < part)) { + if (!finfo || copied <= finfo->dirty_offset) { maybe_trouble = true; iov_iter_revert(iter, copied); copied = 0; folio_unlock(folio); goto retry; } - __netfs_set_group(folio, netfs_group); - folio_mark_uptodate(folio); - trace = netfs_whole_folio_modify; + + /* We overwrote some existing dirty data, so we have to + * accept the partial write. + */ + finfo->dirty_len += finfo->dirty_offset; + if (finfo->dirty_len == flen) { + trace = netfs_whole_folio_modify_filled_efault; + goto folio_now_filled; + } + if (copied > finfo->dirty_len) + finfo->dirty_len = copied; + finfo->dirty_offset = 0; + trace = netfs_whole_folio_modify_efault; goto copied; } @@ -327,16 +347,10 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, goto copy_failed; finfo->dirty_len += copied; if (finfo->dirty_offset == 0 && finfo->dirty_len == flen) { - if (finfo->netfs_group) - folio_change_private(folio, finfo->netfs_group); - else - folio_detach_private(folio); - folio_mark_uptodate(folio); - kfree(finfo); trace = netfs_streaming_cont_filled_page; - } else { - trace = netfs_streaming_write_cont; + goto folio_now_filled; } + trace = netfs_streaming_write_cont; goto copied; } @@ -350,6 +364,13 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, goto out; continue; + folio_now_filled: + if (finfo->netfs_group) + folio_change_private(folio, finfo->netfs_group); + else + folio_detach_private(folio); + folio_mark_uptodate(folio); + kfree(finfo); copied: trace_netfs_folio(folio, trace); flush_dcache_folio(folio); diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h index 0b702f74aefe..aa9940ba307b 100644 --- a/include/trace/events/netfs.h +++ b/include/trace/events/netfs.h @@ -177,6 +177,9 @@ EM(netfs_folio_is_uptodate, "mod-uptodate") \ EM(netfs_just_prefetch, "mod-prefetch") \ EM(netfs_whole_folio_modify, "mod-whole-f") \ + EM(netfs_whole_folio_modify_efault, "mod-whole-f!") \ + EM(netfs_whole_folio_modify_filled, "mod-whole-f+") \ + EM(netfs_whole_folio_modify_filled_efault, "mod-whole-f+!") \ EM(netfs_modify_and_clear, "mod-n-clear") \ EM(netfs_streaming_write, "mod-streamw") \ EM(netfs_streaming_write_cont, "mod-streamw+") \ -- cgit v1.2.3 From ccde2ac757c713535b224233a296de40efe5212d Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 12 May 2026 13:33:58 +0100 Subject: netfs: Fix folio->private handling in netfs_perform_write() Under some circumstances, netfs_perform_write() doesn't correctly manipulate folio->private between NULL, NETFS_FOLIO_COPY_TO_CACHE, pointing to a group and pointing to a netfs_folio struct, leading to potential multiple attachments of private data with associated folio ref leaks and also leaks of netfs_folio structs or netfs_group refs. Fix this by consolidating the place at which a folio is marked uptodate in one place and having that look at what's attached to folio->private and decide how to clean it up and then set the new group. Also, the content shouldn't be flushed if group is NULL, even if a group is specified in the netfs_group parameter, as that would be the case for a new folio. A filesystem should always specify netfs_group or never specify netfs_group. The Sashiko auto-review tool noted that it was theoretically possible that the fpos >= ctx->zero_point section might leak if it modified a streaming write folio. This is unlikely, but with a network filesystem, third party changes can happen. It also pointed out that __netfs_set_group() would leak if called multiple times on the same folio from the "whole folio modify section". Fixes: 8f52de0077ba ("netfs: Reduce number of conditional branches in netfs_perform_write()") Closes: https://sashiko.dev/#/patchset/20260414082004.3756080-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-22-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- fs/netfs/buffered_write.c | 134 ++++++++++++++++++++++++++----------------- include/trace/events/netfs.h | 1 + 2 files changed, 82 insertions(+), 53 deletions(-) (limited to 'include/trace') diff --git a/fs/netfs/buffered_write.c b/fs/netfs/buffered_write.c index f79fb5996540..6bde3320bcec 100644 --- a/fs/netfs/buffered_write.c +++ b/fs/netfs/buffered_write.c @@ -12,24 +12,6 @@ #include #include "internal.h" -static void __netfs_set_group(struct folio *folio, struct netfs_group *netfs_group) -{ - if (netfs_group) - folio_attach_private(folio, netfs_get_group(netfs_group)); -} - -static void netfs_set_group(struct folio *folio, struct netfs_group *netfs_group) -{ - void *priv = folio_get_private(folio); - - if (unlikely(priv != netfs_group)) { - if (netfs_group && (!priv || priv == NETFS_FOLIO_COPY_TO_CACHE)) - folio_attach_private(folio, netfs_get_group(netfs_group)); - else if (!netfs_group && priv == NETFS_FOLIO_COPY_TO_CACHE) - folio_detach_private(folio); - } -} - /* * Grab a folio for writing and lock it. Attempt to allocate as large a folio * as possible to hold as much of the remaining length as possible in one go. @@ -157,6 +139,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, size_t offset; /* Offset into pagecache folio */ size_t part; /* Bytes to write to folio */ size_t copied; /* Bytes copied from user */ + void *priv; offset = pos & (max_chunk - 1); part = min(max_chunk - offset, iov_iter_count(iter)); @@ -202,6 +185,25 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, goto error_folio_unlock; } + finfo = netfs_folio_info(folio); + group = netfs_folio_group(folio); + + /* If the requested group differs from the group set on the + * page, then we need to flush out the folio if it has a group + * set (ie. is non-NULL). Note that COPY_TO_CACHE is a special + * case, being a netfs annotation rather than an actual group. + * + * The filesystem isn't permitted to mix writes with groups and + * writes without groups as the NULL group is used to indicate + * that no group is set. + */ + if (unlikely(group != netfs_group) && + group != NETFS_FOLIO_COPY_TO_CACHE && + group) { + WARN_ON_ONCE(!netfs_group); + goto flush_content; + } + /* Decide how we should modify a folio. We might be attempting * to do write-streaming, as we don't want to a local RMW cycle * if we can avoid it. If we're doing local caching or content @@ -209,22 +211,14 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, * file is open readably, then we let ->read_folio() fill in * the gaps. */ - finfo = netfs_folio_info(folio); - group = netfs_folio_group(folio); - - if (unlikely(group != netfs_group) && - group != NETFS_FOLIO_COPY_TO_CACHE) - goto flush_content; - if (folio_test_uptodate(folio)) { if (mapping_writably_mapped(mapping)) flush_dcache_folio(folio); copied = copy_folio_from_iter_atomic(folio, offset, part, iter); if (unlikely(copied == 0)) goto copy_failed; - netfs_set_group(folio, netfs_group); trace = netfs_folio_is_uptodate; - goto copied; + goto copied_uptodate; } /* If the page is above the zero-point then we assume that the @@ -237,24 +231,22 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, if (unlikely(copied == 0)) goto copy_failed; folio_zero_segment(folio, offset + copied, flen); - __netfs_set_group(folio, netfs_group); - folio_mark_uptodate(folio); - trace = netfs_modify_and_clear; - goto copied; + if (finfo) + trace = netfs_modify_and_clear_rm_finfo; + else + trace = netfs_modify_and_clear; + goto mark_uptodate; } /* See if we can write a whole folio in one go. */ if (!maybe_trouble && offset == 0 && part >= flen) { copied = copy_folio_from_iter_atomic(folio, offset, part, iter); if (likely(copied == part)) { - if (finfo) { + if (finfo) trace = netfs_whole_folio_modify_filled; - goto folio_now_filled; - } - __netfs_set_group(folio, netfs_group); - folio_mark_uptodate(folio); - trace = netfs_whole_folio_modify; - goto copied; + else + trace = netfs_whole_folio_modify; + goto mark_uptodate; } if (copied == 0) goto copy_failed; @@ -272,7 +264,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, finfo->dirty_len += finfo->dirty_offset; if (finfo->dirty_len == flen) { trace = netfs_whole_folio_modify_filled_efault; - goto folio_now_filled; + goto mark_uptodate; } if (copied > finfo->dirty_len) finfo->dirty_len = copied; @@ -300,11 +292,11 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, copied = copy_folio_from_iter_atomic(folio, offset, part, iter); if (unlikely(copied == 0)) goto copy_failed; - netfs_set_group(folio, netfs_group); trace = netfs_just_prefetch; - goto copied; + goto copied_uptodate; } + /* Do a streaming write on a folio that has nothing in it yet. */ if (!finfo) { ret = -EIO; if (WARN_ON(folio_get_private(folio))) @@ -313,10 +305,8 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, if (unlikely(copied == 0)) goto copy_failed; if (offset == 0 && copied == flen) { - __netfs_set_group(folio, netfs_group); - folio_mark_uptodate(folio); trace = netfs_streaming_filled_page; - goto copied; + goto mark_uptodate; } finfo = kzalloc_obj(*finfo); @@ -345,7 +335,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, finfo->dirty_len += copied; if (finfo->dirty_offset == 0 && finfo->dirty_len == flen) { trace = netfs_streaming_cont_filled_page; - goto folio_now_filled; + goto mark_uptodate; } trace = netfs_streaming_write_cont; goto copied; @@ -361,13 +351,36 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter, goto out; continue; - folio_now_filled: - if (finfo->netfs_group) - folio_change_private(folio, finfo->netfs_group); - else - folio_detach_private(folio); + /* Mark a folio as being up to data when we've filled it + * completely. If the folio has a group attached, then it must + * be the same group, otherwise we should have flushed it out + * above. We have to get rid of the netfs_folio struct if + * there was one. + */ + mark_uptodate: folio_mark_uptodate(folio); - kfree(finfo); + + copied_uptodate: + priv = folio_get_private(folio); + if (likely(priv == netfs_group)) { + /* Already set correctly; no change required. */ + } else if (priv == NETFS_FOLIO_COPY_TO_CACHE) { + if (!netfs_group) + folio_detach_private(folio); + else + folio_change_private(folio, netfs_get_group(netfs_group)); + } else if (!priv) { + folio_attach_private(folio, netfs_get_group(netfs_group)); + } else { + WARN_ON_ONCE(!finfo); + if (netfs_group) + /* finfo->netfs_group has a ref */ + folio_change_private(folio, netfs_group); + else + folio_detach_private(folio); + kfree(finfo); + } + copied: trace_netfs_folio(folio, trace); flush_dcache_folio(folio); @@ -530,6 +543,7 @@ vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf, struct netfs_group *netfs_gr struct inode *inode = file_inode(file); struct netfs_inode *ictx = netfs_inode(inode); vm_fault_t ret = VM_FAULT_NOPAGE; + void *priv; int err; _enter("%lx", folio->index); @@ -550,7 +564,9 @@ vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf, struct netfs_group *netfs_gr } group = netfs_folio_group(folio); - if (group != netfs_group && group != NETFS_FOLIO_COPY_TO_CACHE) { + if (group && + group != netfs_group && + group != NETFS_FOLIO_COPY_TO_CACHE) { folio_unlock(folio); err = filemap_fdatawrite_range(mapping, folio_pos(folio), @@ -572,7 +588,19 @@ vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf, struct netfs_group *netfs_gr trace_netfs_folio(folio, netfs_folio_trace_mkwrite_plus); else trace_netfs_folio(folio, netfs_folio_trace_mkwrite); - netfs_set_group(folio, netfs_group); + + priv = folio_get_private(folio); + if (priv != netfs_group) { + if (!netfs_group && priv == NETFS_FOLIO_COPY_TO_CACHE) + folio_detach_private(folio); + else if (netfs_group && priv == NETFS_FOLIO_COPY_TO_CACHE) + folio_change_private(folio, netfs_get_group(netfs_group)); + else if (netfs_group && !priv) + folio_attach_private(folio, netfs_get_group(netfs_group)); + else + WARN_ON_ONCE(1); + } + file_update_time(file); set_bit(NETFS_ICTX_MODIFIED_ATTR, &ictx->flags); if (ictx->ops->post_modify) diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h index aa9940ba307b..082cb03c6131 100644 --- a/include/trace/events/netfs.h +++ b/include/trace/events/netfs.h @@ -181,6 +181,7 @@ EM(netfs_whole_folio_modify_filled, "mod-whole-f+") \ EM(netfs_whole_folio_modify_filled_efault, "mod-whole-f+!") \ EM(netfs_modify_and_clear, "mod-n-clear") \ + EM(netfs_modify_and_clear_rm_finfo, "mod-n-clear+") \ EM(netfs_streaming_write, "mod-streamw") \ EM(netfs_streaming_write_cont, "mod-streamw+") \ EM(netfs_flush_content, "flush") \ -- cgit v1.2.3 From 620072fd783290ad92c2d445a47b0a61b161f352 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Sun, 26 Apr 2026 12:31:17 -0700 Subject: mm/damon: fix damos_stat tracepoint format for sz_applied The print format is wrongly marking sz_applied as sz_tried. Fix it. Link: https://lore.kernel.org/20260426193119.88095-1-sj@kernel.org Fixes: 804c26b961da ("mm/damon/core: add trace point for damos stat per apply interval") Signed-off-by: SeongJae Park Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Steven Rostedt Cc: # 7.0.x Signed-off-by: Andrew Morton --- include/trace/events/damon.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/trace') diff --git a/include/trace/events/damon.h b/include/trace/events/damon.h index 24fc402ab3c8..7e25f4469b81 100644 --- a/include/trace/events/damon.h +++ b/include/trace/events/damon.h @@ -41,7 +41,7 @@ TRACE_EVENT(damos_stat_after_apply_interval, ), TP_printk("ctx_idx=%u scheme_idx=%u nr_tried=%lu sz_tried=%lu " - "nr_applied=%lu sz_tried=%lu sz_ops_filter_passed=%lu " + "nr_applied=%lu sz_applied=%lu sz_ops_filter_passed=%lu " "qt_exceeds=%lu nr_snapshots=%lu", __entry->context_idx, __entry->scheme_idx, __entry->nr_tried, __entry->sz_tried, -- cgit v1.2.3 From 2b50aceafe6606ea52ed42aadd1b4d44a188aade Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 16 May 2026 00:05:13 +0100 Subject: crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks Change the krb5 crypto library to provide facilities to precheck the length of the message about to be decrypted or verified. Fix AF_RXRPC to make use of this to validate DATA packets secured with RxGK. Fixes: 9d1d2b59341f ("rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)") Closes: https://sashiko.dev/#/patchset/20260511160753.607296-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Herbert Xu cc: Simon Horman cc: Chuck Lever cc: linux-afs@lists.infradead.org Reviewed-by: Jeffrey Altman Tested-by: Marc Dionne Link: https://patch.msgid.link/20260515230516.2718212-2-dhowells@redhat.com Signed-off-by: Jakub Kicinski --- Documentation/crypto/krb5.rst | 17 ++++++++++---- crypto/krb5/krb5_api.c | 54 ++++++++++++++++++++++++++++++++++++++----- include/crypto/krb5.h | 9 +++++--- include/trace/events/rxrpc.h | 1 + net/rxrpc/rxgk.c | 15 ++++++++++-- 5 files changed, 81 insertions(+), 15 deletions(-) (limited to 'include/trace') diff --git a/Documentation/crypto/krb5.rst b/Documentation/crypto/krb5.rst index beffa0133446..f62e07ac6811 100644 --- a/Documentation/crypto/krb5.rst +++ b/Documentation/crypto/krb5.rst @@ -158,13 +158,22 @@ returned. When a message has been received, the location and size of the data with the message can be determined by calling:: - void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, - enum krb5_crypto_mode mode, - size_t *_offset, size_t *_len); + int crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t *_offset, size_t *_len); The caller provides the offset and length of the message to the function, which then alters those values to indicate the region containing the data (plus any -padding). It is up to the caller to determine how much padding there is. +padding). It is up to the caller to determine how much padding there is. The +function returns an error if the length is too small or if the mode is +unsupported. An additional function:: + + int crypto_krb5_check_data_len(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t len, size_t min_content); + +is provided to just do a basic check that the decrypted/verified message would +have a sufficient minimum payload. Preparation Functions --------------------- diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c index 23026d4206c8..c7ea40f900a7 100644 --- a/crypto/krb5/krb5_api.c +++ b/crypto/krb5/krb5_api.c @@ -134,27 +134,69 @@ EXPORT_SYMBOL(crypto_krb5_how_much_data); * Find the offset and size of the data in a secure message so that this * information can be used in the metadata buffer which will get added to the * digest by crypto_krb5_verify_mic(). + * + * Return: 0 if successful, -EBADMSG if the message is too short or -EINVAL if + * the mode is unsupported. */ -void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, - enum krb5_crypto_mode mode, - size_t *_offset, size_t *_len) +int crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t *_offset, size_t *_len) { switch (mode) { case KRB5_CHECKSUM_MODE: + if (*_len < krb5->cksum_len) + return -EBADMSG; *_offset += krb5->cksum_len; *_len -= krb5->cksum_len; - return; + return 0; case KRB5_ENCRYPT_MODE: + if (*_len < krb5->conf_len + krb5->cksum_len) + return -EBADMSG; *_offset += krb5->conf_len; *_len -= krb5->conf_len + krb5->cksum_len; - return; + return 0; default: WARN_ON_ONCE(1); - return; + return -EINVAL; } } EXPORT_SYMBOL(crypto_krb5_where_is_the_data); +/** + * crypto_krb5_check_data_len - Check a message is big enough + * @krb5: The encoding to use. + * @mode: Mode of operation. + * @len: The length of the secure blob. + * @min_content: Minimum length of the content inside the blob. + * + * Check that a message is large enough to hold whatever bits the encryption + * type wants to glue on (nonce, checksum) plus a minimum amount of content. + * + * Return: 0 if successful, -EBADMSG if the message is too short or -EINVAL if + * the mode is unsupported. + */ +int crypto_krb5_check_data_len(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t len, size_t min_content) +{ + switch (mode) { + case KRB5_CHECKSUM_MODE: + if (len < krb5->cksum_len || + len - krb5->cksum_len < min_content) + return -EBADMSG; + return 0; + case KRB5_ENCRYPT_MODE: + if (len < krb5->conf_len + krb5->cksum_len || + len - (krb5->conf_len + krb5->cksum_len) < min_content) + return -EBADMSG; + return 0; + default: + WARN_ON_ONCE(1); + return -EINVAL; + } +} +EXPORT_SYMBOL(crypto_krb5_check_data_len); + /* * Prepare the encryption with derived key data. */ diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h index 71dd38f59be1..aac3ecf88467 100644 --- a/include/crypto/krb5.h +++ b/include/crypto/krb5.h @@ -121,9 +121,12 @@ size_t crypto_krb5_how_much_buffer(const struct krb5_enctype *krb5, size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5, enum krb5_crypto_mode mode, size_t *_buffer_size, size_t *_offset); -void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, - enum krb5_crypto_mode mode, - size_t *_offset, size_t *_len); +int crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t *_offset, size_t *_len); +int crypto_krb5_check_data_len(const struct krb5_enctype *krb5, + enum krb5_crypto_mode mode, + size_t len, size_t min_content); struct crypto_aead *crypto_krb5_prepare_encryption(const struct krb5_enctype *krb5, const struct krb5_buffer *TK, u32 usage, gfp_t gfp); diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h index 573f2df3a2c9..704a10de6670 100644 --- a/include/trace/events/rxrpc.h +++ b/include/trace/events/rxrpc.h @@ -71,6 +71,7 @@ EM(rxkad_abort_resp_unknown_tkt, "rxkad-resp-unknown-tkt") \ EM(rxkad_abort_resp_version, "rxkad-resp-version") \ /* RxGK security errors */ \ + EM(rxgk_abort_1_short_header, "rxgk1-short-hdr") \ EM(rxgk_abort_1_verify_mic_eproto, "rxgk1-vfy-mic-eproto") \ EM(rxgk_abort_2_decrypt_eproto, "rxgk2-dec-eproto") \ EM(rxgk_abort_2_short_data, "rxgk2-short-data") \ diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c index 0d5e654da918..26e723052a37 100644 --- a/net/rxrpc/rxgk.c +++ b/net/rxrpc/rxgk.c @@ -480,8 +480,12 @@ static int rxgk_verify_packet_integrity(struct rxrpc_call *call, _enter(""); - crypto_krb5_where_is_the_data(gk->krb5, KRB5_CHECKSUM_MODE, - &data_offset, &data_len); + if (crypto_krb5_where_is_the_data(gk->krb5, KRB5_CHECKSUM_MODE, + &data_offset, &data_len) < 0) { + ret = rxrpc_abort_eproto(call, skb, RXGK_PACKETSHORT, + rxgk_abort_1_short_header); + goto put_gk; + } hdr = kzalloc_obj(*hdr, GFP_NOFS); if (!hdr) @@ -529,6 +533,13 @@ static int rxgk_verify_packet_encrypted(struct rxrpc_call *call, _enter(""); + if (crypto_krb5_check_data_len(gk->krb5, KRB5_ENCRYPT_MODE, + len, sizeof(hdr)) < 0) { + ret = rxrpc_abort_eproto(call, skb, RXGK_PACKETSHORT, + rxgk_abort_2_short_header); + goto error; + } + ret = rxgk_decrypt_skb(gk->krb5, gk->rx_enc, skb, &offset, &len, &ac); if (ret < 0) { if (ret != -ENOMEM) -- cgit v1.2.3