BMC/Intel-BMC/linux.git/fs/iomap, branch dev-5.15-intel

iomap: Fix inline extent handling in iomap_readpage

2021-12-01T08:04:44+00:00

commit d8af404ffce71448f29bbc19a05e3d095baf98eb upstream. Before commit 740499c78408 ("iomap: fix the iomap_readpage_actor return value for inline data"), when hitting an IOMAP_INLINE extent, iomap_readpage_actor would report having read the entire page. Since then, it only reports having read the inline data (iomap->length). This will force iomap_readpage into another iteration, and the filesystem will report an unaligned hole after the IOMAP_INLINE extent. But iomap_readpage_actor (now iomap_readpage_iter) isn't prepared to deal with unaligned extents, it will get things wrong on filesystems with a block size smaller than the page size, and we'll eventually run into the following warning in iomap_iter_advance: WARN_ON_ONCE(iter->processed > iomap_length(iter)); Fix that by changing iomap_readpage_iter to return 0 when hitting an inline extent; this will cause iomap_iter to stop immediately. To fix readahead as well, change iomap_readahead_iter to pass on iomap_readpage_iter return values less than or equal to zero. Fixes: 740499c78408 ("iomap: fix the iomap_readpage_actor return value for inline data") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Andreas Gruenbacher Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Signed-off-by: Greg Kroah-Hartman

iomap: standardize tracepoint formatting and storage

2021-08-26T16:18:53+00:00

Print all the offset, pos, and length quantities in hexadecimal. While we're at it, update the types of the tracepoint structure fields to match the types of the values being recorded in them. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Dave Chinner

mm/swap: consider max pages in iomap_swapfile_add_extent

2021-08-18T19:47:52+00:00

When the max pages (last_page in the swap header + 1) is smaller than the total pages (inode size) of the swapfile, iomap_swapfile_activate overwrites sis->max with total pages. However, frontswap_map is a swap page state bitmap allocated using the initial sis->max page count read from the swap header. If swapfile activation increases sis->max, it's possible for the frontswap code to walk off the end of the bitmap, thereby corrupting kernel memory. [djwong: modify the description a bit; the original paragraph reads: "However, frontswap_map is allocated using max pages. When test and clear the sis offset, which is larger than max pages, of frontswap_map in __frontswap_invalidate_page(), neighbors of frontswap_map may be overwritten, i.e., slab is polluted." Note also that this bug resulted in a behavioral change: activating a swap file that was formatted and later extended results in all pages being activated, not the number of pages recorded in the swap header.] This fixes the issue by considering the limitation of max pages of swap info in iomap_swapfile_add_extent(). To reproduce the case, compile kernel with slub RED ZONE, then run test: $ sudo stress-ng -a 1 -x softlockup,resources -t 72h --metrics --times \ --verify -v -Y /root/tmpdir/stress-ng/stress-statistic-12.yaml \ --log-file /root/tmpdir/stress-ng/stress-logfile-12.txt \ --temp-path /root/tmpdir/stress-ng/ We'll get the error log as below: [ 1151.015141] ============================================================================= [ 1151.016489] BUG kmalloc-16 (Not tainted): Right Redzone overwritten [ 1151.017486] ----------------------------------------------------------------------------- [ 1151.017486] [ 1151.018997] Disabling lock debugging due to kernel taint [ 1151.019873] INFO: 0x0000000084e43932-0x0000000098d17cae @offset=7392. First byte 0x0 instead of 0xcc [ 1151.021303] INFO: Allocated in __do_sys_swapon+0xcf6/0x1170 age=43417 cpu=9 pid=3816 [ 1151.022538] __slab_alloc+0xe/0x20 [ 1151.023069] __kmalloc_node+0xfd/0x4b0 [ 1151.023704] __do_sys_swapon+0xcf6/0x1170 [ 1151.024346] do_syscall_64+0x33/0x40 [ 1151.024925] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1151.025749] INFO: Freed in put_cred_rcu+0xa1/0xc0 age=43424 cpu=3 pid=2041 [ 1151.026889] kfree+0x276/0x2b0 [ 1151.027405] put_cred_rcu+0xa1/0xc0 [ 1151.027949] rcu_do_batch+0x17d/0x410 [ 1151.028566] rcu_core+0x14e/0x2b0 [ 1151.029084] __do_softirq+0x101/0x29e [ 1151.029645] asm_call_irq_on_stack+0x12/0x20 [ 1151.030381] do_softirq_own_stack+0x37/0x40 [ 1151.031037] do_softirq.part.15+0x2b/0x30 [ 1151.031710] __local_bh_enable_ip+0x4b/0x50 [ 1151.032412] copy_fpstate_to_sigframe+0x111/0x360 [ 1151.033197] __setup_rt_frame+0xce/0x480 [ 1151.033809] arch_do_signal+0x1a3/0x250 [ 1151.034463] exit_to_user_mode_prepare+0xcf/0x110 [ 1151.035242] syscall_exit_to_user_mode+0x27/0x190 [ 1151.035970] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1151.036795] INFO: Slab 0x000000003b9de4dc objects=44 used=9 fp=0x00000000539e349e flags=0xfffffc0010201 [ 1151.038323] INFO: Object 0x000000004855ba01 @offset=7376 fp=0x0000000000000000 [ 1151.038323] [ 1151.039683] Redzone 000000008d0afd3d: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ [ 1151.041180] Object 000000004855ba01: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1151.042714] Redzone 0000000084e43932: 00 00 00 c0 cc cc cc cc ........ [ 1151.044120] Padding 000000000864c042: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ [ 1151.045615] CPU: 5 PID: 3816 Comm: stress-ng Tainted: G B 5.10.50+ #7 [ 1151.046846] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 1151.048633] Call Trace: [ 1151.049072] dump_stack+0x57/0x6a [ 1151.049585] check_bytes_and_report+0xed/0x110 [ 1151.050320] check_object+0x1eb/0x290 [ 1151.050924] ? __x64_sys_swapoff+0x39a/0x540 [ 1151.051646] free_debug_processing+0x151/0x350 [ 1151.052333] __slab_free+0x21a/0x3a0 [ 1151.052938] ? _cond_resched+0x2d/0x40 [ 1151.053529] ? __vunmap+0x1de/0x220 [ 1151.054139] ? __x64_sys_swapoff+0x39a/0x540 [ 1151.054796] ? kfree+0x276/0x2b0 [ 1151.055307] kfree+0x276/0x2b0 [ 1151.055832] __x64_sys_swapoff+0x39a/0x540 [ 1151.056466] do_syscall_64+0x33/0x40 [ 1151.057084] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1151.057866] RIP: 0033:0x150340b0ffb7 [ 1151.058481] Code: Unable to access opcode bytes at RIP 0x150340b0ff8d. [ 1151.059537] RSP: 002b:00007fff7f4ee238 EFLAGS: 00000246 ORIG_RAX: 00000000000000a8 [ 1151.060768] RAX: ffffffffffffffda RBX: 00007fff7f4ee66c RCX: 0000150340b0ffb7 [ 1151.061904] RDX: 000000000000000a RSI: 0000000000018094 RDI: 00007fff7f4ee860 [ 1151.063033] RBP: 00007fff7f4ef980 R08: 0000000000000000 R09: 0000150340a672bd [ 1151.064135] R10: 00007fff7f4edca0 R11: 0000000000000246 R12: 0000000000018094 [ 1151.065253] R13: 0000000000000005 R14: 000000000160d930 R15: 00007fff7f4ee66c [ 1151.066413] FIX kmalloc-16: Restoring 0x0000000084e43932-0x0000000098d17cae=0xcc [ 1151.066413] [ 1151.067890] FIX kmalloc-16: Object at 0x000000004855ba01 not freed Fixes: 67482129cdab ("iomap: add a swapfile activation function") Fixes: a45c0eccc564 ("iomap: move the swapfile code into a separate file") Signed-off-by: Gang Deng Signed-off-by: Xu Yu Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig

iomap: move loop control code to iter.c

2021-08-17T04:26:33+00:00

Now that we've moved iomap to the iterator model, rename this file to be in sync with the functions contained inside of it. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner

iomap: constify iomap_iter_srcmap

2021-08-17T04:26:33+00:00

The srcmap returned from iomap_iter_srcmap is never modified, so mark the iomap returned from it const and constify a lot of code that never modifies the iomap. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

iomap: rework unshare flag

2021-08-17T04:26:33+00:00

Instead of another internal flags namespace inside of buffered-io.c, just pass a UNSHARE hint in the main iomap flags field. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

iomap: pass an iomap_iter to various buffered I/O helpers

2021-08-17T04:26:33+00:00

Pass the iomap_iter structure instead of individual parameters to various internal helpers for buffered I/O. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

iomap: remove iomap_apply

2021-08-17T04:26:33+00:00

iomap_apply is unused now, so remove it. Signed-off-by: Christoph Hellwig [djwong: rebase this patch to preserve git history of iomap loop control] Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner

iomap: switch iomap_swapfile_activate to use iomap_iter

2021-08-17T04:26:33+00:00

Switch iomap_swapfile_activate to use iomap_iter. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

iomap: switch iomap_seek_data to use iomap_iter

2021-08-17T04:26:33+00:00

Rewrite iomap_seek_data to use iomap_iter. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong