fs/vfs/fs_fstat.c: fix write capability check in proxy_fstat()#18746
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michallenc merged 1 commit intoapache:masterfrom Apr 16, 2026
Merged
fs/vfs/fs_fstat.c: fix write capability check in proxy_fstat()#18746michallenc merged 1 commit intoapache:masterfrom
michallenc merged 1 commit intoapache:masterfrom
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In proxy_fstat(), the write permission bits for a block driver proxy were gated on `i_ops->read` instead of `i_ops->write`: The effect is that a driver implementing read but not write would have S_IWOTH | S_IWGRP | S_IWUSR incorrectly set in the fstat() result, reporting the file as writable when it is not. Fix: replace `->read` with `->write` in the write check condition. Signed-off-by: Abhishek Mishra <mishra.abhishek2808@gmail.com>
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In
proxy_fstat(), when detecting a block driver proxy , the condition that sets the write permission bits(S_IWOTH | S_IWGRP | S_IWUSR)in thefstat() result incorrectly checkedi_ops->readinstead ofi_ops->write. As a result, any block driver proxy that implements read but not write would be incorrectly reported as writable byfstat()This is a one-line fix with no behavioural change for any driver that implements both
readandwrite(the common case). Only drivers that implementreadbut notwriteare affected, and for them the fix corrects a wrong permission report.